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Sample records for ac-20 asphalt binder

  1. Characterization of asphalt additive produced from hydroretorted Alabama shale

    SciTech Connect

    Rue, D.M.; Roberts, M.J.

    1992-12-31

    Shale oil, produced from beneficiated Alabama shale by pressurized fluidized-bed hydroretorting, was fractionated to produce shale oil asphalt additives (SOA). Three shale oil fractions boiling above 305{degrees}C were added to standard AC-20 asphalt to improve pavement properties. The physical properties and aging characteristics of AC-20 asphalt binder (cement) containing SOA are similar to those of unmodified AC-20 asphalt binder. Asphalt pavement briquettes made with AC-20 asphalt binder containing 5 to 10 percent SOA have superior resistance to freeze-thaw cracking and a greater retention of tensile strength when wet compared to pavement briquettes containing AC-20 binder alone.

  2. Effect of moisture on the aging behavior of asphalt binder

    NASA Astrophysics Data System (ADS)

    Ma, Tao; Huang, Xiao-Ming; Mahmoud, Enad; Garibaldy, Emil

    2011-08-01

    The moisture aging effect and mechanism of asphalt binder during the in-service life of pavement were investigated by laboratory simulating tests. Pressure aging vessel (PAV) test simulating the long-term aging of binder during the in-service life of pavement was modified to capture the long-term moisture aging effect of binder. Penetration grade tests including penetration test, soften point test, and ductility test as well as Superpave™ performance grade tests including viscosity test, dynamic shear rheometer test, and bending beam rheometer test were conducted to fully evaluate the moisture aging effect of binder. Fourier transform infrared spectroscopy test and Gel-permeation chromatography test were applied to provide a fundamental understanding of the moisture aging mechanism of binder. The results indicate that moisture condition can accelerate the aging of asphalt binder and shorten the service life of asphalt binder. The modified PAV test with moisture condition can well characterize the moisture aging properties of asphalt binder.

  3. Sustainable asphalt pavement: Application of slaughterhouse waste oil and fly ash in asphalt binder

    NASA Astrophysics Data System (ADS)

    Sanchez Ramos, Jorge Luis

    Increasing energy costs, lack of sufficient natural resources and the overwhelming demand for petroleum has stimulated the development of alternative binders to modify or replace petroleum-based asphalt binders. In the United States, the petroleum-based asphalt binder is mainly used to produce the Hot Mix Asphalt (HMA). There are approximately 4000 asphalt plants that make 500 million tons of asphalt binder valued at roughly 3 billion/year. The instability of the world's oil market has pushed oil prices to more than 80 per barrel in 2012, which increased the cost of asphalt binder up to $570 per ton. Therefore, there is a timely need to find alternative sustainable resources to the asphalt binder. This paper investigates the possibility of the partial replacement of the asphalt binder with slaughterhouse waste and/or fly ash. In order to achieve this objective, the asphalt binder is mixed with different percentages of waste oil and/or fly ash. In order to investigate the effect of these additives to the performance of the asphalt binder, a complete performance grade test performed on multiple samples. The results of the performance grade tests are compared with a control sample to observe how the addition of the waste oil and/or fly ash affects the sample. Considering the increasing cost and demand of asphalt, the use of slaughterhouse waste oil and/or fly ash as a partial replacement may result in environmental and monetary improvements in the transportation sector.

  4. Dynamic linear viscoelastic properties and extensional failure of asphalt binders

    NASA Astrophysics Data System (ADS)

    Ruan, Yonghong

    Billions of dollars are spent annually in USA to maintain old pavements that are badly cracked. In order to reduce this expenditure, it is desirable to have criteria for selecting asphalts with superior cracking resistance that will provide pavements with longer durability. Literature reports indicate that the ductility of binders recovered from asphalt pavements correlates with cracking failure. However, ductility measurement is a time and material consuming process, and subject to reproducibility difficulties, as are all failure tests. In addition, ductility measurement does not belong to the currently used Superpave(TM) specification. Correlations between ductility and dynamic viscoelastic properties (measured with the dynamic shear rheometer, DSR), which are much easier and faster to perform and may be included into the Superpave(TM) system, are studied for both straight and modified binders. Ductility correlates quite well with G'/(eta '/G') for conventional asphalt binders aged at different conditions, especially when ductility is below 10 cm. However, for modified asphalts, there is no universal correlation between ductility and G'/(eta'/G'), even in the low ductility region. As far as the asphalt binder in pavement is concerned, the loss due to oxidative aging of its ductility is an important reason for pavement cracking. Polymer modification modifies the rheological and oxidative hardening properties of asphalt binders. The effect of polymeric modifiers on various properties of asphalt binders was investigated. Modifiers studied were diblock poly (styrene-b-butadiene) rubber (SBR), triblock poly (styrene-b-butadiene-b-styrene) (SBS), and tire rubber. Polymer modified binders have a lower hardening and oxidation rate than their corresponding base asphalts. In addition, modified binders have lower hardening susceptibility compared with their base materials and in some cases the results can be dramatic. Polymer modification improves asphalt binders' shear

  5. Effect of pyrolyzed carbon black on asphalt cement. Part 2. Asphalt binder. Final report, September 1993-May 1995

    SciTech Connect

    Zeng, Y.; Lovell, C.W.

    1996-02-20

    Scrap tires derived from automobiles have become a large environmental problem in the United States. In the study, research is carried out to investigate the potential use of tire-derived pyrolyzed carbon black from scrap tires as an asphalt cement modifier. The asphlat cements used in the research were AC10 and AC20. Penetration and softening point tests were performed to obtain the consistency of the asphalt cements. The pyrolyzed carbon black, as provided by Wolf Industries, was combined with the asphalt cement in the following percentages: 5%, 10%, 15% and 20%. Penetration, softening point and ductility tests were performed to determine the temperature susceptibility of the modified binder as altered by the pyrolyzed carbon black. In order that the results are comparable to previous testing, commercial carbon black purchased from CABOT Industry was also used as a modifier in the tests. The same test procedures were applied to the asphalt cements modified by commercial carbon black. The test results contained in the report illustrate the viability of the pyrolyzed carbon black as an asphalt modifier. Recommendations are provided to facilitate further research on this particular project. A preliminary assessment of a test road using the pyrolyzed carbon is appended.

  6. Modified Asphalt Binder with Natural Zeolite for Warm Mix Asphalt

    NASA Astrophysics Data System (ADS)

    Dubravský, Marián; Mandula, Ján

    2015-11-01

    In recent years, warm mix asphalt (WMA) is becoming more and more used in the asphalt industry. WMA provide a whole range of benefits, whether economic, environmental and ecological. Lower energy consumption and less pollution is the most advantages of this asphalt mixture. The paper deals with the addition of natural zeolite into the sub base asphalt layers, which is the essential constituent in the construction of the road. Measurement is focused on basic physic - mechanical properties declared according to the catalog data sheets. The aim of this article is to demonstrate the ability of addition the natural zeolite into the all asphalt layers of asphalt pavement. All asphalt mixtures were compared with reference asphalt mixture, which was prepared in reference temperature.

  7. Linking asphalt binder fatigue to asphalt mixture fatigue performance using viscoelastic continuum damage modeling

    NASA Astrophysics Data System (ADS)

    Safaei, Farinaz; Castorena, Cassie; Kim, Y. Richard

    2016-08-01

    Fatigue cracking is a major form of distress in asphalt pavements. Asphalt binder is the weakest asphalt concrete constituent and, thus, plays a critical role in determining the fatigue resistance of pavements. Therefore, the ability to characterize and model the inherent fatigue performance of an asphalt binder is a necessary first step to design mixtures and pavements that are not susceptible to premature fatigue failure. The simplified viscoelastic continuum damage (S-VECD) model has been used successfully by researchers to predict the damage evolution in asphalt mixtures for various traffic and climatic conditions using limited uniaxial test data. In this study, the S-VECD model, developed for asphalt mixtures, is adapted for asphalt binders tested under cyclic torsion in a dynamic shear rheometer. Derivation of the model framework is presented. The model is verified by producing damage characteristic curves that are both temperature- and loading history-independent based on time sweep tests, given that the effects of plasticity and adhesion loss on the material behavior are minimal. The applicability of the S-VECD model to the accelerated loading that is inherent of the linear amplitude sweep test is demonstrated, which reveals reasonable performance predictions, but with some loss in accuracy compared to time sweep tests due to the confounding effects of nonlinearity imposed by the high strain amplitudes included in the test. The asphalt binder S-VECD model is validated through comparisons to asphalt mixture S-VECD model results derived from cyclic direct tension tests and Accelerated Loading Facility performance tests. The results demonstrate good agreement between the asphalt binder and mixture test results and pavement performance, indicating that the developed model framework is able to capture the asphalt binder's contribution to mixture fatigue and pavement fatigue cracking performance.

  8. Design of open graded friction courses with sulfur extended asphalt binders

    NASA Astrophysics Data System (ADS)

    Saylak, D.; Ho, K. K.; Gallaway, B. M.; Little, D. N.

    1982-09-01

    The combination of the anticipated shortage of asphalt cement and the projected abundance of sulfur has led to the investigation of the potential for substituting this element for the former in the paving industry. Sulfur was incorporated with asphalt to form sulfur-extended asphalt (SEA) binders for use in open graded friction course mixtures. The experimental design variable included aggregated type, asphalt cement, level of sulfur contents in the binder and method of preparing SEA binders.

  9. Rheology of crumb-rubber modified asphalt binders and mixes

    NASA Astrophysics Data System (ADS)

    Sheth, Vikas Rameshchandra

    Laboratory test procedures are presented to determine the rheological properties of crumb rubber modified asphalt (CRMA) binders and mixes. These tests provide simple, fast, and cost-effective alternatives to evaluate the performance (rutting and cracking potential) of binders and mixes used for pavement construction. Viscoelastic properties of CRMA binders are measured using dynamic shear analysis. Master curves were generated using the principle of time-temperature superposition to evaluate the effects of aging, rubber concentration, and curing conditions on the rheology of the modified binder. Results indicate that the rheology of CRMA binders can be divided into three regions of viscoelasticity: glassy region at high frequencies, transition/viscoelastic region at intermediate frequencies, and viscous region at low frequencies. Modification of the asphalt by addition of rubber leads to an improvement in both the high and low temperature properties, as reflected by changes in Gsp' and Gsp{''}, which causes the binder to have a greater resistance to specific pavement failure mechanisms. Both transient and dynamic properties of CRMA mixes were measured in the laboratory using the creep and recovery, direct tension, and frequency sweep tests. Rheological properties of the mix generated from the test data were compared to those of the binder to evaluate the effect of aging, rubber concentration, and curing conditions on mix performance. Several rheological parameters have been identified to characterize the rutting and cracking potential of mixes. A power law equation was found to give good correlations between several mix rheological parameters. Analysis of binder and mix failure energies show that work of cohesion of the binder is negligible compared to the failure energies. A unique relationship between Paris law material parameters has been confirmed. It is also shown that mix failure properties bear a one-to-one correlation with binder failure properties. Based

  10. Investigation of the curing variables of asphalt-rubber binder

    SciTech Connect

    Billiter, T.C.; Chun, J.S.; Davison, R.R.

    1996-12-31

    Currently, the paving industry utilizes a curing time of 1 hour at 177{degrees}C (350{degrees}F) for producing asphalt-rubber binder. Billiter et al. showed that at these curing conditions, 1 hour at 177{degrees}C (350{degrees}F), adding rubber to asphalt was beneficial, with the rubber improving the low-temperature creep stiffness at (-15{degrees}C (5{degrees}F)), the temperature susceptibility in the 0{degrees}C-90{degrees}C (32{degrees}F-194{degrees}F) temperature region, increasing G* and {eta}* at 60{degrees}C (140{degrees}F) and 1.0 rad/sec, and decreasing 8 at 60{degrees}C (140{degrees}F) and 1.0 rad/sec. On the other hand, Billiter et al. (2) showed that the addition of rubber was also detrimental, in that the viscosity increased significantly in the compaction temperature region of 149{degrees}C-193{degrees}C (300{degrees}F-380{degrees}F). This increased viscosity can cause compaction problems, with Allison reporting that engineers blamed the compaction problems of asphalt-rubber on undissolved crumb rubber, which they believed had no beneficial effect. Additionally, the engineers reported that improper compaction led to early road failure. This work investigates the variables of binders, curing tenperature and time, and amount of mechancial energy on asphalt properties.

  11. Using the poker-chip test for determining the bulk modulus of asphalt binders

    NASA Astrophysics Data System (ADS)

    Motamed, Arash; Bhasin, Amit; Liechti, Kenneth M.

    2014-02-01

    The properties of asphalt binders strongly influence the overall mechanical response of asphalt mixture composites. A thorough understanding of the mechanistic behavior of asphalt binders is important in order to fully and accurately characterize the behavior of the asphalt mixture. The mechanical properties of the asphalt binder, the matrix in the asphalt mixture composite, are time and temperature dependent and have a lower stiffness compared to the inclusions (aggregate particles). However, computational methods used to model the micromechanics of asphalt mixtures typically assume a constant bulk modulus or Poisson's ratio for asphalt binders. This research investigates the time-dependence of the bulk modulus of asphalt binders. Several approaches for measuring the bulk modulus were explored and the poker-chip geometry was found to be the most suitable one. The boundary value problem for the poker-chip geometry was solved to determine the bulk modulus and Poisson's ratio of asphalt binders as a function of time. The findings from this research improve our understanding of the viscoelastic behavior of asphaltic materials, and also guide important assumptions that are typically made during computational modeling of asphaltic materials.

  12. Evaluation of Thermal Oxidative Aging Effect on the Rheological Performance of Modified Asphalt Binders

    NASA Astrophysics Data System (ADS)

    Zhu, Cheng

    Modified asphalt binder, which is combined by base binder and additive modifier, has been implemented in pavement industry for more than 30 years. Recently, the oxidative aging mechanism of asphalt binder has been studied for several decades, and appreciable finding results of asphalt binder aging mechanism were achieved from the chemistry and rheological performance aspects. However, most of these studies were conducted with neat binders, the research of aging mechanism of modified asphalt binder was limited. Nowadays, it is still highly necessary to clarify how the asphalt binder aging happens with the modified asphalt binder, what is the effect of the different modifiers (additives) on the binder aging process, how the rheological performance changes under the thermal oxidative aging conditions and so on. The objective of this study was to investigate the effect of isothermal oxidative aging conditions on the rheological performance change of the modified and controlled asphalt binders. There were totally 14 different sorts of asphalt binders had been aged in the PAV pans in the air-force drafted ovens at 50°C, 60°C and 85°C for 0.5 day to 240 days. The Fourier-Transform Infrared Spectroscopy (FT-IR) and Dynamic Shear Rheometer (DSR) were used to perform the experiments. The analysis of rheological indices (Low shear viscosity-LSV, Crossover modulus-G*c, Glover-Rowe Parameter-G-R, DSR function-DSR Fn) as a function of carbonyl area (CA) was conducted. With the SBS modification, both of the hardening susceptibility of the rheological index-LSV and G-R decreases compared with the corresponding base binder. The TR increased the hardening susceptibility of all the rheological indexes. While for the G*c, SBS increases the slope of the most modified asphalt binders except A and B_TR_X series binders. The multiple linear regression statistical analysis results indicate that the oxidative aging conditions play an important role on the CA, and rheological performance

  13. Measurements of thermal and healing properties of nanoclay modified asphalt binders using molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Baker, Dustin; Hawa, Takumi; Hossain, Zahid; Saha, Mrinal; Zaman, Musharraf

    2014-03-01

    A seven component molecular dynamics model has been developed to represent asphalt binder. The model has been developed to include the four major classes of molecules found in asphalt binders. The seven asphalt binder molecules were assembled with the Optimized Potentials for Liquid Simulations force field (OPLS) and the Large-scale atomic/molecular massively parallel simulator (LAMMPS) was used to carry out all simulations. Diffusion and density values were determined to validate individual molecules; all values were within acceptable range. Diffusion values were also determined for each molecule while present in the asphalt binder mixture. Density of the asphalt binder was determined to compare to experimental results. Values appear to follow the same trend as seen in experimental results and were closer to experimental results than other asphalt binder models. A glass transition temperature of 263.59K was determined using the density results at nineteen temperatures and was found to be in an acceptable range. A nano-clay model has also been developed using Clay force field and combined with the asphalt binder model. Also, we have investigated how the nano-clay impacts thermal and healing properties of the binder.

  14. Rubber modified and performance based asphalt binder pavements: I-5 Nisqually River to Gravelly Lake. Post construction report

    SciTech Connect

    Pierce, L.M.

    1996-01-01

    The report describes the construction of asphalt pavements made with three types of asphalt binders. The three types of binders were PBA-6, PBA-6GR (ground rubber), and AR4000W. The two modified binders, PBA-6 and PBA-6GR, are being evaluated to determine their resistance to rutting as compared to the conventional binder, AR4000W.

  15. Relating tensile, bending, and shear test data of asphalt binders to pavement performance

    SciTech Connect

    Chen, J.S.; Tsai, C.J.

    1998-12-01

    Eight different asphalt binders representing a wide range of applications for pavement construction were tested in uniaxial tension, bending, and shear stresses. Theoretical analyses were performed in this study to covert the data from the three engineering tests to stiffness moduli for predicting pavement performance. At low temperatures, high asphalt stiffness may induce pavement thermal cracking; thus, the allowable maximum stiffness was set at 1,000 MPa. At high temperatures, low asphalt stiffness may lead to pavement rutting (ruts in the road); master curves were constructed to rank the potential for rutting in the asphalts. All three viscoelastic functions were shown to be interchangeable within the linear viscoelastic region. When subjected to large deformation in the direct tension test, asphalt binders behaved nonlinear viscoelastic in which the data under bending, shear and tension modes were not comparable. The asphalts were, however, found toe exhibit linear viscoelasticity up to the failure point in the steady-state strain region.

  16. Enhancing Asphalt Binder's Rheological Behavior and Aging Susceptibility Using Nano-Particles

    NASA Astrophysics Data System (ADS)

    Walters, Renaldo C.

    The life expectancy of Asphalt Binder (AB) has been negatively impacted by the harsh bombardment of UV rays. UV rays cause asphalt to oxidize faster which results in deterioration of asphalt rheological characteristics that can lead to pavement distresses. This study investigates the impact that nano-particles and bio modification have on the aging susceptibility of asphalt binder. As such, the following hypothesis was investigated: Introduction of nano particles to asphalt binder will reduce asphalt oxidation aging by increasing the inter layer spacing of the nano particles. Two nano scale materials were used for this study, nano-clay and bio-char as well as one micro scale material, silica fume. Nano-clay (Cloisite 30B) is a naturally occurring inorganic mineral. Bio-char is the waste product from bio-binder production. Bio-binder is produced from swine manure using a thermochemical conversion process. This process is then followed by a filtration procedure where the bio-char is produced. Chemical and physical properties of bio-char showed a significant presence of carbon which could in turn reduce the rate of asphalt oxidation. Silica Fume is an ultra-fine powder collected as a by-product of silicon and ferrosilicon alloy production and consists of spherical particles. In this study several mixtures are designed and evaluated using RV testing (Rotational Viscometer), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). Nano-clay is blended at 2% and 4% by weight of dry mass, with and without bio-binder (5% by weight of dry mass). Bio-char is grinded to nano scale and added to the virgin asphalt binder (PG 64-22) at 2%, 5% and 10% by weight of dry mass. Silica Fume is added to virgin asphalt binder (PG 64-22) at 2%, 4% and 8% by weight of dry mass. The optimum percent of nano scale material that is added to virgin asphalt binder is expected to reduce aging susceptibility of asphalt binder, extending its service life.

  17. Estimation of low-temperature cracking threshold for asphalt binders using an acoustic emmission approach

    NASA Astrophysics Data System (ADS)

    Apeagyei, Alex K.; Buttlar, William G.; Reis, Henrique

    2009-03-01

    An acoustic emission (AE) approach to evaluate low temperature cracking susceptibility of asphalt binders is presented. Thin films of asphalt binders were bonded to granite substrates and exposed to temperatures ranging from 15°C to - 50°C. Differential thermal contraction between granite substrates and asphalt binders induces progressively higher thermal stress in the binders resulting in thermal crack formation, which is accompanied by a release of elastic energy in the form of transient waves. Using piezoelectric sensors (Digital Wave, Model B-1025), a four-channel acoustic emission system was used to record the acoustic emission activity during the binder/granite cooling process. Assuming the cracking temperature (Tcr) to be the temperature at which the AE signal energy exceeds a pre-selected threshold energy level, this AE testing approach was found to be sensitive and repeatable for predicting cracking temperatures (Tcr) in four SUPERPAVE core asphalt binders. These AE-based Tcr predictions showed strong correlation (R2 = 0.9) with predictions based on either AASHTO TP1 or MP1A protocols. Unlike TP1 and MP1A protocols, the presented AE approach does not require the use of sophisticated software for predicting thermal stresses, and no assumption is required regarding the testing cooling rate and the binder coefficient of thermal contraction.

  18. Monitoring viscosity in asphalt binders using an ultrasonic guided wave approach

    NASA Astrophysics Data System (ADS)

    Haser, Alexandra N.; McGovern, Megan E.; Behnia, Behzad; Buttlar, William; Reis, Henrique

    2015-03-01

    A pulse-echo ultrasonic guided wave approach capable of monitoring the viscosity of asphalt binders as function of temperature is presented. The method consists of sending a torsional wave from one end of a cylindrical steel rod embedded in asphalt binder and receiving the reflected signals. Experiments were performed on several binders of different performance grades, at temperatures ranging from 25 to 1800C. First, the viscosity of the binders was measured using a rotational viscometer in accordance with ASTM standards. The change in signal strength of the end-of-waveguide reflection of the guided wave was also monitored for the same binders over the same range of temperatures. It was observed that the values obtained using the guided wave approach correlates well with the viscosity values obtained using the rotational viscometer. The method also appears capable of monitoring changes in viscosity due to aging of the binders. The method has the advantage of having no moving parts, which makes it attractive for the development of a system that is capable of monitoring viscosity in asphalt binders in the asphalt industry. Industrial applications examples are briefly summarized.

  19. Black curves and creep behaviour of crumb rubber modified binders containing warm mix asphalt additives

    NASA Astrophysics Data System (ADS)

    Gallego, Juan; Rodríguez-Alloza, Ana María; Giuliani, Felice

    2016-08-01

    Warm mix asphalt (WMA) is a new research topic in the field of road pavement materials. This technology allows lower energy consumption and greenhouse gas (GHG) emissions by reducing compaction and placement temperatures of the asphalt mixtures. However, this technology is still under study, and the influence of the WMA additives has yet to be investigated thoroughly and clearly identified, especially in the case of crumb rubber modified (CRM) binders.

  20. How good are linear viscoelastic properties of asphalt binder to predict rutting and fatigue cracking

    SciTech Connect

    Chen, J.S.; Tsai, C.J. . Dept. of Civil Engineering)

    1999-08-01

    This article evaluates the effects of linear viscoelastic properties of asphalt on pavement rutting and fatigue cracking. The parameters in the binder specification recently developed by the Strategic Highway Research Program (SHRP) were also compared for pavement performance. Two studies were conducted for asphalt-aggregate mixes. The first study was the wheel tracking test to evaluate the rutting of mixes containing three asphalts. The second study was a detailed field study of the effects of binder properties on the pavement performance of eight different sections. Results of both investigations indicated that SHRP parameters were not sufficient indicators for predicting the rutting and fatigue cracking of pavements. The discrepancies between performance data and existing parameters of the binder mainly resulted from the inherited assumptions made during the specification development, that is, stress- or strain-controlled mode and traffic loading frequency. In order to directly relate the linear viscoelastic properties of asphalt binders to pavement performance, calculating the dissipated energy per traffic cycle, W[sub d], became imperative. Fundamental derivation of W[sub d] was developed in this study. Results indicated that W[sub d] could predict the rutting and fatigue cracking of pavements reasonably well, This study, proposed the dissipated energy, W[sub d], as the single parameter for evaluating pavement rutting and fatigue cracking.

  1. Optical characterization of temperature- and composition-dependent microstructure in asphalt binders.

    PubMed

    Ramm, A; Sakib, N; Bhasin, A; Downer, M C

    2016-06-01

    We introduce noncontact optical microscopy and optical scattering to characterize asphalt binder microstructure at temperatures ranging from 15°C to 85°C for two compositionally different asphalt binders. We benchmark optical measurements against rheometric measurements of the magnitude of the temperature-dependent bulk complex shear modulus |G*(T)|. The main findings are: (1) Elongated (∼5 × 1 μm), striped microstructures (known from AFM studies as 'bees' because they resemble bumble-bees) are resolved optically, found to reside primarily at the surface and do not reappear immediately after a single heating-cooling cycle. (2) Smaller (∼1 μm(2) ) microstructures with no observable internal structure (hereafter dubbed 'ants'), are found to reside primarily in the bulk, to persist after multiple thermal cycles and to scatter light strongly. Optical scattering from 'ants' decreases to zero with heating from 15°C to 65°C, but recovers completely upon cooling back to 15°C, albeit with distinct hysteresis. (3) Rheometric measurements of |G*(T)| reveal hysteresis that closely resembles that observed by optical scatter, suggesting that thermally driven changes in microstructure volume fraction cause corresponding changes in |G*(T)|. PMID:26594842

  2. Optical Characterization of Temperature- and Composition-Dependent Microstructure in Asphalt Binders

    NASA Astrophysics Data System (ADS)

    Ramm, Adam; Nazmus, Sakib; Bhasin, Amit; Downer, Michael

    We introduce noncontact optical microscopy and optical scattering to characterize asphalt binder microstructure at temperatures ranging from 15 to 85°C for two compositionally different asphalt binders. We benchmark optical measurements against rheometric measurements of the magnitude of the temperature-dependent bulk complex shear modulus | G* (T) | . The main findings are: (1) Elongated (5 x 1 μm), striped microstructures (known from AFM studies as ''bees'' because they resemble bumble-bees) are resolved optically, found to reside primarily at the surface, and do not reappear immediately after a single heating-cooling cycle. (2) Smaller (1 μm2) microstructures with no observable internal structure (hereafter dubbed ``ants''), are found to reside primarily in the bulk, to persist after multiple thermal cycles and to scatter light strongly. Optical scattering from ''ants'' decreases to zero with heating from 15 to 65°C, but recovers completely upon cooling back to 15°C, albeit with distinct hysteresis. (3) Rheometric measurements of | G* (T) | reveal hysteresis that closely resembles that observed by optical scatter, suggesting that thermally-driven changes in microstructure volume fraction cause corresponding changes in | G* (T) | .

  3. Evolution of the microstructure of unmodified and polymer modified asphalt binders with aging in an accelerated weathering tester.

    PubMed

    Menapace, Ilaria; Masad, Eyad

    2016-09-01

    This paper presents findings on the evolution of the surface microstructure of two asphalt binders, one unmodified and one polymer modified, directly exposed to aging agents with increasing durations. The aging is performed using an accelerated weathering tester, where ultraviolet radiation, oxygen and an increased temperature are applied to the asphalt binder surface. Ultraviolet and dark cycles, which simulated the succession of day and night, alternated during the aging process, and also the temperature varied, which corresponded to typical summer day and night temperatures registered in the state of Qatar. Direct aging of an exposed binder surface is more effective in showing microstructural modifications than previously applied protocols, which involved the heat treatment of binders previously aged with standardized methods. With the new protocol, any molecular rearrangements in the binder surface after aging induced by the heat treatment is prevented. Optical photos show the rippling and degradation of the binder surface due to aging. Microstructure images obtained by means of atomic force microscopy show gradual alteration of the surface due to aging. The original relatively flat microstructure was substituted with a profoundly different microstructure, which significantly protrudes from the surface, and is characterized by various shapes, such as rods, round structures and finally 'flower' or 'leaf' structures. PMID:27059404

  4. Evolution of the microstructure of unmodified and polymer modified asphalt binders with aging in an accelerated weathering tester.

    PubMed

    Menapace, Ilaria; Masad, Eyad

    2016-09-01

    This paper presents findings on the evolution of the surface microstructure of two asphalt binders, one unmodified and one polymer modified, directly exposed to aging agents with increasing durations. The aging is performed using an accelerated weathering tester, where ultraviolet radiation, oxygen and an increased temperature are applied to the asphalt binder surface. Ultraviolet and dark cycles, which simulated the succession of day and night, alternated during the aging process, and also the temperature varied, which corresponded to typical summer day and night temperatures registered in the state of Qatar. Direct aging of an exposed binder surface is more effective in showing microstructural modifications than previously applied protocols, which involved the heat treatment of binders previously aged with standardized methods. With the new protocol, any molecular rearrangements in the binder surface after aging induced by the heat treatment is prevented. Optical photos show the rippling and degradation of the binder surface due to aging. Microstructure images obtained by means of atomic force microscopy show gradual alteration of the surface due to aging. The original relatively flat microstructure was substituted with a profoundly different microstructure, which significantly protrudes from the surface, and is characterized by various shapes, such as rods, round structures and finally 'flower' or 'leaf' structures.

  5. Effect of X-ray Line Spectra Profile Fitting with Pearson VII, Pseudo-Voigt and Generalized Fermi Functions on Asphalt Binder Aromaticity and Crystallite Parameters

    NASA Astrophysics Data System (ADS)

    Gebresellasie, K.; Shirokoff, J.; Lewis, J. C.

    2012-12-01

    X-ray line spectra profile fitting using Pearson VII, pseudo-Voigt and generalized Fermi functions was performed on asphalt binders prior to the calculation of aromaticity and crystallite size parameters. The effects of these functions on the results are presented and discussed in terms of the peak profile fit parameters, the uncertainties in calculated values that can arise owing to peak shape, peak features in the pattern and crystallite size according to the asphalt models (Yen, modified Yen or Yen-Mullins) and theories. Interpretation of these results is important in terms of evaluating the performance of asphalt binders widely used in the application of transportation systems (roads, highways, airports).

  6. Effect of treatment temperature on the microstructure of asphalt binders: insights on the development of dispersed domains.

    PubMed

    Menapace, I; Masad, E; Bhasin, A

    2016-04-01

    This paper offers important insights on the development of the microstructure in asphalt binders as a function of the treatment temperature. Different treatment temperatures are useful to understand how dispersed domains form when different driving energies for the mobility of molecular species are provided. Small and flat dispersed domains, with average diameter between 0.02 and 0.70 μm, were detected on the surface of two binders at room temperature, and these domains were observed to grow with an increase in treatment temperature (up to over 2 μm). Bee-like structures started to appear after treatment at or above 100°C. Moreover, the effect of the binder thickness on its microstructure at room temperature and at higher treatment temperatures was investigated and is discussed in this paper. At room temperature, the average size of the dispersed domains increased as the binder thickness decreased. A hypothesis that conciliates current theories on the origin and development of dispersed domains is proposed. Small dispersed domains (average diameter around 0.02 μm) are present in the bulk of the binder, whereas larger domains and bee-like structures develop on the surface, following heat treatment or mechanical disturbance that reduces the film thickness. Molecular mobility and association are the key factors in the development of binder microstructure. PMID:26540203

  7. Effect of treatment temperature on the microstructure of asphalt binders: insights on the development of dispersed domains.

    PubMed

    Menapace, I; Masad, E; Bhasin, A

    2016-04-01

    This paper offers important insights on the development of the microstructure in asphalt binders as a function of the treatment temperature. Different treatment temperatures are useful to understand how dispersed domains form when different driving energies for the mobility of molecular species are provided. Small and flat dispersed domains, with average diameter between 0.02 and 0.70 μm, were detected on the surface of two binders at room temperature, and these domains were observed to grow with an increase in treatment temperature (up to over 2 μm). Bee-like structures started to appear after treatment at or above 100°C. Moreover, the effect of the binder thickness on its microstructure at room temperature and at higher treatment temperatures was investigated and is discussed in this paper. At room temperature, the average size of the dispersed domains increased as the binder thickness decreased. A hypothesis that conciliates current theories on the origin and development of dispersed domains is proposed. Small dispersed domains (average diameter around 0.02 μm) are present in the bulk of the binder, whereas larger domains and bee-like structures develop on the surface, following heat treatment or mechanical disturbance that reduces the film thickness. Molecular mobility and association are the key factors in the development of binder microstructure.

  8. Using pyrolized carbon black from waste tires in asphalt pavement. Part 1. Limestone aggregate. Final report, September 1993-May 1995

    SciTech Connect

    Park, T.; Lovell, C.W.

    1996-02-20

    The study presents the viability of using pyrolyzed carbon black (PCB) as an additive in hot mix asphalt concrete. Different ratios of PCB (5%, 10%, 15%, 20% by weight of asphalt) were blended with two grades of asphalt (AC-10 and AC-20). The complete behaviors of the PCB modified asphalt concrete were investigated by comprehensive laboratory testing and evaluation. The Marshall method was used to determine the optimum binder content, and the mechanical properties and void relationships were investigated by this method. The Gyratory Testing Machine was used to define the stress-strain relationships of the PCB mixtures. The rutting potential of PCB mixtures was investigated using the Dynamic Creep Testing. The performance of the PCB mixtures at low temperature (5 degrees C) was determined by the Indirect Tensile Testing. The strength performance of the PCB mixtures at intermediate temperatures (5 degrees C and 25 degrees C) was examined by the Resilient Modulus Test. The Hamburg Wheel Tracking Device was employed to ascertain the stripping potential of the PCB mixtures. The findings of the study show beneficial effects of added PCB for asphalt mixture. Specifically, test results show that PCB contents of 10% to 15% by weigh of asphalt produce a number of significant 0mprovements. The rutting potential, the temperature susceptibility and the stripping potential can be reduced by the inclusion of PCB in the asphalt mixture. Added material costs of about 6% may well be justified by expected improvements in performance.

  9. Oxidation and photooxidation of asphalts

    SciTech Connect

    Mill, T.; Tse, D. )

    1990-07-01

    Oxidation of asphalt is a major cause of pavement failure owing to hardening of the asphalt binder with accompanying changes in viscosity, separation of components, embrittlement and loss of cohesion and adhesion of the asphalt in the mix. However oxidation of asphalt-aggregate mixes at high temperature is deliberately done to partly harden the mix prior to laydown; hardening then continues during cooling. Excessive hardening at this point is undesirable because of embrittlement and cracking. Slow oxidation of asphalt continues during the service life of the roadbed at a rate that appears to be partly determined by the void volume of the roadbed, as well as the properties of the asphalt and (possibly) the properties of the aggregate. The authors focused their efforts on understanding the mechanistic basis for slow oxidation of asphalt under service conditions in order to predict how rapidly an asphalt will oxidize, based on its composition, and to find better ways to inhibit the process under service conditions.

  10. Investigation of factors affecting asphalt pavement recycling and asphalt compatibility

    SciTech Connect

    Venable, R.L.; Petersen, J.C.; Robertson, R.E.; Plancher, H.

    1983-03-01

    Both economic and environmental factors dictate that asphalt pavement be recycled. Many recycling projects have been completed using a variety of recycling additives, but little work has been done on the physiochemical aspects of pavement recycling. The present exploratory study was undertaken to better define the physiochemical variables of recycling. Objectives of the present study include: (1) to determine if molecular structuring in the asphalt binder could be observed in oxidized (air-aged) asphalt-aggregate briquets, and if so, how was structuring affected during briquits, and if so, how was structuring affected during briquet recycling and (2) to determine if recycling agents penetrate the strongly adsorbed asphalt layer on the aggregate surface. Differences were seen in asphalt component compatibility as judged by the state of peptization parameters. In extreme cases the values of the parameters correlated with properties of asphalts of known compatibility; however, a relationship between the parameters determined on a series of asphalts in pavements was not established. The parameters might be useful in evaluating additives for pavement recycling; however, more systems need to be studied to fully assess their potential usefulness. Finally, the parameters need to be correlated with performance-related measurements such as asphalt rheological and mix properties. Examination of the parameters and their changes on asphalt oxidative aging may also be informative with regard to asphalt durability inasmuch as oxidation-induced changes are a major cause of asphalt pavement failure.

  11. Rheological properties of asphalts with particulate additives

    SciTech Connect

    Shashidhar, N.; Chollar, B.H.

    1996-12-31

    The Superpave asphalt binder specifications are performance-based specifications for purchasing asphalt binders for the construction of roads. This means that the asphalt is characterized by fundamental material (rheological) properties that relate to the distress modes of the pavements. The distress modes addressed are primarily rutting, fatigue cracking and low temperature cracking. For example, G*/sin({delta}) is designed to predict the rutting potential of pavements, where G* is the magnitude of the complex shear modulus and 6 is the phase angle. The binder for a road that is situated in a certain climatic zone requires the binder to have a minimum G*/sin({delta}) of 2200 Pa at the highest consecutive 7-day average pavement temperature the road had experienced. Implicit in such a performance based specification is that the fundamental property, G*/sin({delta}), of the binder correlates with rutting potential of the pavement regardless of the nature of the binder. In other words, the specification is transparent to the fact that the binder can simply be an asphalt, or an asphalt modified by polymers, particulates and other materials that can form a two-phase mixture. This paper discusses the asphalt-particulate system.

  12. MATCON MODIFIED ASPHALT COVER CONTAINMENT SYSTEM DEMONSTRATION

    EPA Science Inventory

    In order to make improvements to conventional paving asphalt to make it more suitable for containment applications, Wilder Construction Co. of Everett, WA offers MatCon, a polymer modified asphalt system comprised of proprietary binder, when coupled with a selected aggregate type...

  13. Recycled rubber, aggregate, and filler in asphalt paving mixtures. Transportation research record

    SciTech Connect

    1996-12-31

    ;Contents(Partial): Evaluation Systems for Crumb Rubber Modified Binders and Mixtures; Hot Mix Asphalt Rubber Applications in Virginia; Evaluation of Pyrolized Carbon Black from Scrap Tires as Additive in Hot Mix Asphalt; Use of Scrap Tire Chips in Asphaltic Membrane; Effects of Mineral Fillers on Properties of Stone Matrix Asphalt Mixtures; and Quantitative Analysis of Aggregate Based on Hough Transform.

  14. Supercritical fractions as asphalt recycling agents and preliminary aging studies on recycled asphalts

    SciTech Connect

    Chaffin, J.M.; Liu, M.; Davison, R.R.; Glover, C.J.; Bullin, J.A.

    1997-03-01

    Several asphalts were fractionated using supercritical pentane. These fractions were analyzed by gel permeation chromatography and high-performance liquid chromatography, and their viscosities were measured. The properties of these fractions vary not only among the fractions of a given asphalt but also for the same fraction produced from different asphalts. These widely varied fractions previously have been shown to have potential for reblending to produce superior asphalts. This study investigates the potential for using some of the fractions as asphalt recycling agents. A modified strategic highway research program (SHRP) pressure aging vessel (PAV) test and kinetics studies were conducted on nine recycled asphalts and the original asphalt. The aging indexes of eight of the recycled asphalts are superior to the aging index of the original asphalt. Two of the blends using industrial supercritical fractions and the three blends using laboratory supercritical fractions have lower aging indexes than blends using commercial recycling agents. The kinetics investigation also indicates that at road conditions the recycled asphalts will harden more slowly than the original asphalt. The degree of hardening for a given amount of oxidation in the recycled binders was found to be a strong function of the total saturate content in the recycled binder.

  15. Feasibility of using 100% Recycled Asphalt Pavement mixtures for road construction

    NASA Astrophysics Data System (ADS)

    Carlson, Russell Edgar, IV

    Recycled Asphalt Pavement (RAP) is the largest recycled good in the United States and 80 million tons are recycled yearly, saving taxpayers about $1.5 billion dollars. This paper explores the possibility of utilizing 100% RAP materials in asphalt pavement. Asphalt mixtures are produced at 135°C in a typical asphalt plant. However, at 135°C, not all binder from RAP materials may not become effective for coating aggregates. The main objective of the study is to determine the amount of effective binder available from RAP in the asphalt plant. The 100% RAP mixes have aged binder that can alter mix designs and interaction with virgin binder. In this study, to determine low temperature cracking resistance and fatigue performance, samples were prepared using a 100% RAP mix with no virgin binder and a 100% RAP mix with virgin asphalt binder to achieve the optimum binder content of the mix. Second, to determine the effectiveness of binder from RAP materials, compaction tests were performed by heating RAP materials at various temperatures. It was found that 100% RAP mixes cannot be feasible for field use if additional virgin binder is added to reach the optimum asphalt content. Based on limited test results, the low temperature grade was not within proper limits but the beam fatigue testing results were acceptable. Based on compaction test results, additional heating is needed to increase the effectiveness of asphalt binder from RAP materials.

  16. Contributions of performance-graded asphalt to low temperature cracking resistance of pavements. Final report

    SciTech Connect

    Loh, S.W.; Olek, J.

    1999-05-01

    The purpose of this research was to study and evaluate the role that asphalt cracking. As part of the Strategic Highway Research Program (SHRP) new specifications for asphalt binders were developed that are based on the performance of the material. The asphalt binder graded and specified according to these new performance-based specifications is called PG binder. These new specifications are commonly referred to as Superpave (Superior Performing Asphalt Pavement) binder specifications. A section of Interstate 64 in southern Indiana was experiencing severe low temperature cracking before it was reconstructed over the summers of 1995 and 1996. The binder used in the new pavement mixes was PG material. Dynamic Shear Rheometer (DSR) tests, Bending Beam Rheometer (BBR) tests, and viscosity tests were performed on this binder. Comparisons were made between test results obtained from the binders in the old pavement and the new pavement. All tests and comparisons were based on the Superpave binder specifications.

  17. Investigation of modified asphalt concrete

    NASA Astrophysics Data System (ADS)

    Zimich, Vita

    2016-01-01

    Currently the problem of improving the asphalt quality is very urgent. It is used primarily as topcoats exposed to the greatest relative to the other layers of the road, dynamic load - impact and shear. The number of cars on the road, the speed of their movement, as well as the traffic intensity increase day by day. We have to upgrade motor roads, which entails a huge cost. World experience shows that the issue is urgent not only in Russia, but also in many countries in Europe, USA and Asia. Thus, the subject of research is the resistance of asphalt concrete to water and its influence on the strength of the material at different temperatures, and resistance of pavement to deformation. It is appropriate to search for new modifiers for asphaltic binder and mineral additives for asphalt mix to form in complex the skeleton of the future asphalt concrete, resistant to atmospheric condensation, soil characteristics of the road construction area, as well as the growing road transport load. The important task of the work is searching special modifying additives for bitumen binder and asphalt mixture as a whole, which will improve the quality of highways, increasing the period between repairs. The methods described in the normative-technical documentation were used for the research. The conducted research allowed reducing the frequency of road maintenance for 7 years, increasing it from 17 to 25 years.

  18. Influence of roofing shingles on asphalt concrete mixture properties. Final report, 1992-1993

    SciTech Connect

    Newcomb, D.; Stroup-Gardiner, M.; Weikle, B.; Drescher, A.

    1993-06-01

    The objective of the study was to evaluate the use of waste shingles from manufacturing and roof reconstruction projects in hot mix asphalt concrete mixtures. In dense-graded asphalt mixtures, it was hypothesized that the waste material might serve as an extender for the new asphalt in the mix as well as a fiber reinforcement. In the stone mastic asphalt (SMA), it could serve as the binder stiffener typically used to prevent the asphalt from draining out of these types of mixtures.

  19. Evaluation of products recovered from scrap tires for use as asphalt modifiers

    SciTech Connect

    McKay, J.

    1992-05-01

    Western Research Institute performed rheological tests and water sensitivity tests on asphalt cements that had been modified with carbonous residues obtained from the pyrolysis of scrap tires and waste motor oil. These tests are part of an ongoing program at the University of Wyoming Chemical Engineering Department to evaluate, as asphalt additives, solid carbonous products recovered from the scrap tire and waste motor oil pyrolysis experiments conducted at the University. The tests showed that carbonous residues increased the viscosity and decreased the elasticity of AC-10 and AC-20 asphalts. The tests also indicatedthat asphalt cements modified with carbonous residues were less sensitive to water damage and age embrittlement than unmodified asphalt cements.

  20. Improving the quality of asphalt coating with carbon nanomodifiers

    NASA Astrophysics Data System (ADS)

    Larisa, Urkhanova; Nikolay, Shestakov; Aleksandr, Semenov; Natalya, Smirnyagina; Irina, Semenova

    2015-07-01

    This article deals with the possibility of modifying the binder by adding carbon nanomodifier to bitumen to improve the quality of asphalt. Addition of 0.05%-0.5% of nanomodifier significantly changes the properties of bitumen. Asphalt with this astringent has increased strength, heat resistance and shear resistance.

  1. Compatibilizer for crumb rubber modified asphalt

    SciTech Connect

    Labib, M.E.; Memon, G.M.; Chollar, B.H.

    1996-12-31

    The United States of America discards more than 300 million tires each year, and out of that a large fraction of the tires is dumped into stock piles. This large quantity of tires creates an environmental problem. The use of scrap tires is limited. There is a usage potential in such fields as fuel for combustion and Crumb Rubber-Modified Asphalt binder (CRMA). The use of crumb rubber in modifying asphalt is not a new technique; it is been used since early 1960 by pavement engineers. Crumb rubber is a composite of different blends of natural and synthetic rubber (natural rubber, processing oils, polybutadiene, polystyrene butadiene, and filler). Prior research had concluded that the performance of crumb rubber modified asphalt is asphalt dependent. In some cases it improves the Theological properties and in some cases it degrades the properties of modified asphalt.

  2. [Phosphate binders].

    PubMed

    Heeb, Rita M

    2016-06-01

    Phosphate binders to treat hyperphosphataemia are part of the medication regime of every dialysis patient. Phosphate binders are taken with every meal (three times a day). Generally, the medication adherence rates of phosphate binders are very low. This is due to inconveniences like their bad taste or their size which makes them hard to swallow. Also nephrologists have differing opinions on phosphate binders as they are aware of the dialysis patients' difficulties to deal with the amount of drugs they are prescribed. Still, phosphate binders are important drugs which have shown potential in reducing mortality by regulating the level of serum phosphate. In order to improve adherence rates, pharmacists have to advise the patients on these drugs' side effects versus the risks associated with omitting their intake. PMID:27439258

  3. Current practices for modification of paving asphalts

    SciTech Connect

    Bahia, H.U.; Perdomo, D.

    1996-12-31

    The Superpave binder specification, AASHTO MP1, has introduced new concepts for selecting paving asphalt binders. The specification, in addition to using rheological and failure measurements that are more related to performance, is based on the idea that the criteria to maintain a satisfactory contribution of asphalt binders to the resistance of pavement failures remains the same but have to be satisfied at critical application temperatures. The test procedures require that the material be characterized within certain ranges of strains or stresses to ensure that material and geometric non-linearities are not confounded in the measurements. These new specification concepts have resulted in re-evaluation of asphalt modification by the majority of modified asphalt suppliers. The philosophy of asphalt modification is expected to change, following these new concepts, from a general improvement of quality to more focus on using modifiers based on the most critical need as defined by two factors: (1) The application temperature domain and (2) the type of distress to be remedied. The new specification requirements should result in a more effective use of modifiers as the amount and type of modifier will be directly related to the application environment and the engineering requirements.

  4. State-of-the art guideline manual for design, quality control and construction of Sulfur-Extended-Asphalt (SEA) pavements

    NASA Astrophysics Data System (ADS)

    McBee, W. C.; Sullivan, T. A.; Izatt, J. O.

    1980-08-01

    Sulfur-Extended-Asphalt (SEA) binders save asphalt, a potential energy source, by replacing some asphalt in conventional flexible pavement mixes with sulfur. These new binders appear to possess properties comparable to asphalt. The guideline manual discussed provides the highway community in both public and private organizations with the most definitive state-of-the-art guidelines extant for using these binders. Information on design, construction, quality control, equipment, mixing plants, specifications, and safety is included. Administrators and professionals in pavement construction, design, maintenance, and materials testing will be the personnel who are most interested in the manual.

  5. Reclaimed manufacturer asphalt roofing shingles in asphalt mixtures. Final research report

    SciTech Connect

    Reed, A.B.

    1999-04-23

    The purpose of this project was to pave a test section using hot mix asphalt with roofing shingle pieces in the wearing and binder courses and to evaluate. The test project near Allentown, PA plus two other test projects in 1998 provide evidence of very good pavement performance. The bituminous concrete mix was modified with shredded shingles with a maximum size of 1/2 inch which added 1% of the asphalt content. The Department issued a statewide Provisional Specification titled Reclaimed Manufacturer Asphalt Roofing Shingles in Plant-Mixed Bituminous Concrete Courses'' on March 15, 1999. New manufacturer asphalt roofing shingle scrap including tab punch-outs can be successfully incorporated in bituminous concrete pavements if the shingles are shredded to 100% passing the 3/4 inch sieve. To take full advantage of the potential to replace a portion of the asphalt and therefore, reduce mix costs, shingles should be shredded to 100% passing minus 1/2 inch sieve.

  6. Asphalt and asphalt additives. Transportation research record

    SciTech Connect

    Not Available

    1992-01-01

    Contents: use of asphalt emulsions for in-place recycling: oregon experience; gap-graded cold asphalt concrete: benefits of polymer-modified asphalt cement and fibers; cold in-place recycling for rehabilitation and widening of low-volume flexible pavements in indiana; in situ cold recycling of bituminous pavements with polymer-modified high float emulsions; evaluation of new generation of antistripping additives; correlation between performance-related characteristics of asphalt cement and its physicochemical parameters using corbett's fractions and hpgc; reaction rates and hardening susceptibilities as determined from pressure oxygen vessel aging of asphalts; evaluation of aging characteristics of asphalts by using tfot and rtfot at different temperature levels; summary of asphalt additive performance at selected sites; relating asphalt absorption to properties of asphalt cement and aggregate; study of the effectiveness of styrene-butadiene rubber latex in hot mix asphalt mixes; stability of straight and polymer-modified asphalts.

  7. Evaluation of properties of recycled asphalt concrete hot mix

    SciTech Connect

    Brown, E.R.

    1983-01-01

    This study was undertaken to evaluate the laboratory performance of recycled asphalt concrete mixtures and to compare these results to those measured for conventional asphalt concrete mixtures. To make these comparisons, samples of aged asphalt concrete were obtained from three locations where recycling was planned. These samples were blended with new aggregate and new asphalt materials to produce six different recycled mixtures. Two aggregate types, a crushed gravel and a crushed limestone, were used to produce two conventional mixtures and to blend with the reclaimed asphalt pavement to produce the six recycled mixtures. Three asphalt materials which were obtained to produce the various mixtures being evaluated consisted of AC-20 for preparing the conventional mixtures and AC-5 and a recycling agent for preparing the recycled mixtures. The Shell BISAR computer program was used to predict the stesses and strains for two typical pavement sections under a given loading conditions. The computed stresses and strains were then analyzed along with the laboratory fatigue tests to predict the fatigue performance of the various mixtures. The results of this study indicated a satisfactory comparison between laboratory performance of recycled mixtures and conventional mixtures. Fatigue analysis indicated that the conventional mixtures would provide the greatest fatigue resistance in thick asphalt concrete layers at lower temperatures while the recycled mixtures would provide the greatest fatigue resistance in thin asphalt layers at higher temperatures.

  8. Analysis of Adhesive Characteristics of Asphalt Based on Atomic Force Microscopy and Molecular Dynamics Simulation.

    PubMed

    Xu, Meng; Yi, Junyan; Feng, Decheng; Huang, Yudong; Wang, Dongsheng

    2016-05-18

    Asphalt binder is a very important building material in infrastructure construction; it is commonly mixed with mineral aggregate and used to produce asphalt concrete. Owing to the large differences in physical and chemical properties between asphalt and aggregate, adhesive bonds play an important role in determining the performance of asphalt concrete. Although many types of adhesive bonding mechanisms have been proposed to explain the interaction forces between asphalt binder and mineral aggregate, few have been confirmed and characterized. In comparison with chemical interactions, physical adsorption has been considered to play a more important role in adhesive bonding between asphalt and mineral aggregate. In this study, the silicon tip of an atomic force microscope was used to represent silicate minerals in aggregate, and a nanoscale analysis of the characteristics of adhesive bonding between asphalt binder and the silicon tip was conducted via an atomic force microscopy (AFM) test and molecular dynamics (MD) simulations. The results of the measurements and simulations could help in better understanding of the bonding and debonding procedures in asphalt-aggregate mixtures during hot mixing and under traffic loading. MD simulations on a single molecule of a component of asphalt and monocrystalline silicon demonstrate that molecules with a higher atomic density and planar structure, such as three types of asphaltene molecules, can provide greater adhesive strength. However, regarding the real components of asphalt binder, both the MD simulations and AFM test indicate that the colloidal structural behavior of asphalt also has a large influence on the adhesion behavior between asphalt and silicon. A schematic model of the interaction between asphalt and silicon is presented, which can explain the effect of aging on the adhesion behavior of asphalt. PMID:27115043

  9. Analysis of Adhesive Characteristics of Asphalt Based on Atomic Force Microscopy and Molecular Dynamics Simulation.

    PubMed

    Xu, Meng; Yi, Junyan; Feng, Decheng; Huang, Yudong; Wang, Dongsheng

    2016-05-18

    Asphalt binder is a very important building material in infrastructure construction; it is commonly mixed with mineral aggregate and used to produce asphalt concrete. Owing to the large differences in physical and chemical properties between asphalt and aggregate, adhesive bonds play an important role in determining the performance of asphalt concrete. Although many types of adhesive bonding mechanisms have been proposed to explain the interaction forces between asphalt binder and mineral aggregate, few have been confirmed and characterized. In comparison with chemical interactions, physical adsorption has been considered to play a more important role in adhesive bonding between asphalt and mineral aggregate. In this study, the silicon tip of an atomic force microscope was used to represent silicate minerals in aggregate, and a nanoscale analysis of the characteristics of adhesive bonding between asphalt binder and the silicon tip was conducted via an atomic force microscopy (AFM) test and molecular dynamics (MD) simulations. The results of the measurements and simulations could help in better understanding of the bonding and debonding procedures in asphalt-aggregate mixtures during hot mixing and under traffic loading. MD simulations on a single molecule of a component of asphalt and monocrystalline silicon demonstrate that molecules with a higher atomic density and planar structure, such as three types of asphaltene molecules, can provide greater adhesive strength. However, regarding the real components of asphalt binder, both the MD simulations and AFM test indicate that the colloidal structural behavior of asphalt also has a large influence on the adhesion behavior between asphalt and silicon. A schematic model of the interaction between asphalt and silicon is presented, which can explain the effect of aging on the adhesion behavior of asphalt.

  10. Effect of ageing on rheological properties of storage-stable SBS/sulfur-modified asphalts.

    PubMed

    Zhang, Feng; Yu, Jianying; Wu, Shaopeng

    2010-10-15

    Oxidative ageing as an inevitable process in practical road paving has a great effect on the properties of polymer-modified asphalts (PMAs). In this article, the effect of short-term and long-term oxidative ageing on the rheological, physical properties and the morphology of the styrene-butadiene-styrene (SBS)- and storage-stable SBS/sulfur-modified asphalts was studied, respectively. The analysis on the rheological and physical properties of the PMAs before and after ageing showed the two major effects of ageing. On one hand, ageing prompted the degradation of polymer and increased the viscous behaviour of the modified binders, on the other, ageing changed the asphalt compositions and improved the elastic behaviour of the modified binders. The final performance of the aged binders depended on the combined effect. After ageing, the storage-stable SBS/sulfur-modified asphalts showed an obvious viscous behaviour compare with the SBS-modified asphalts and this led to an improved low-temperature creep property. The rutting resistance of the SBS-modified asphalts declined by the addition of sulfur due to the structural instability of the SBS/sulfur-modified asphalts. The rheological properties of the modified binders before and after ageing also depended strongly on the structural characteristics of SBS. The observation by using optical microscopy showed the compatibility between asphalt and SBS was improved with further ageing, especially for the storage-stable SBS/sulfur-modified asphalts.

  11. Effect of ageing on rheological properties of storage-stable SBS/sulfur-modified asphalts.

    PubMed

    Zhang, Feng; Yu, Jianying; Wu, Shaopeng

    2010-10-15

    Oxidative ageing as an inevitable process in practical road paving has a great effect on the properties of polymer-modified asphalts (PMAs). In this article, the effect of short-term and long-term oxidative ageing on the rheological, physical properties and the morphology of the styrene-butadiene-styrene (SBS)- and storage-stable SBS/sulfur-modified asphalts was studied, respectively. The analysis on the rheological and physical properties of the PMAs before and after ageing showed the two major effects of ageing. On one hand, ageing prompted the degradation of polymer and increased the viscous behaviour of the modified binders, on the other, ageing changed the asphalt compositions and improved the elastic behaviour of the modified binders. The final performance of the aged binders depended on the combined effect. After ageing, the storage-stable SBS/sulfur-modified asphalts showed an obvious viscous behaviour compare with the SBS-modified asphalts and this led to an improved low-temperature creep property. The rutting resistance of the SBS-modified asphalts declined by the addition of sulfur due to the structural instability of the SBS/sulfur-modified asphalts. The rheological properties of the modified binders before and after ageing also depended strongly on the structural characteristics of SBS. The observation by using optical microscopy showed the compatibility between asphalt and SBS was improved with further ageing, especially for the storage-stable SBS/sulfur-modified asphalts. PMID:20637542

  12. Bone Glue Modified Asphalt: A Step towards Energy Conservation and Environment Friendly Modified Asphalts.

    PubMed

    Rizvi, Hashim Raza; Khattak, Mohammad Jamal; Gallo, August A

    2014-01-01

    Asphalt has been modified for the past several decades using various additives, including synthetic polymers. Polymer modification improves structural and engineering characteristics of the binder, which is a result of improvement in rheological characteristics of binder as well as its adhesion capability with the aggregate. Such enhancement inevitably enhances the performance characteristics of hot mix asphalts (HMA) such as fatigue life, resistance to rutting, and thermal cracking. Even though polymer-modified HMA is popular in North America and European countries, its use is still limited in developing countries of Southeast Asia due to high costs associated with its manufacturing, processing, and energy consumption. In this study, a new kind of asphalt modifier derived from animal wastes, such as bones, hides, and flesh commonly known as Bone Glue, is studied. This biomaterial which is a by-product of food and cattle industries is cheap, conveniently available, and produced locally in developing countries. The results of the research study showed that the bone glue can easily be mixed with asphalt without significantly altering the asphalt binder's viscosity and mixing and compaction temperatures of HMA. Additionally, improvements in complex shear modulus for a range of temperatures were also determined and it was found that complex shear modulus was improved by bone glue modification.

  13. Bone Glue Modified Asphalt: A Step towards Energy Conservation and Environment Friendly Modified Asphalts

    PubMed Central

    Rizvi, Hashim Raza; Gallo, August A.

    2014-01-01

    Asphalt has been modified for the past several decades using various additives, including synthetic polymers. Polymer modification improves structural and engineering characteristics of the binder, which is a result of improvement in rheological characteristics of binder as well as its adhesion capability with the aggregate. Such enhancement inevitably enhances the performance characteristics of hot mix asphalts (HMA) such as fatigue life, resistance to rutting, and thermal cracking. Even though polymer-modified HMA is popular in North America and European countries, its use is still limited in developing countries of Southeast Asia due to high costs associated with its manufacturing, processing, and energy consumption. In this study, a new kind of asphalt modifier derived from animal wastes, such as bones, hides, and flesh commonly known as Bone Glue, is studied. This biomaterial which is a by-product of food and cattle industries is cheap, conveniently available, and produced locally in developing countries. The results of the research study showed that the bone glue can easily be mixed with asphalt without significantly altering the asphalt binder's viscosity and mixing and compaction temperatures of HMA. Additionally, improvements in complex shear modulus for a range of temperatures were also determined and it was found that complex shear modulus was improved by bone glue modification. PMID:27437456

  14. The Asphalt Handbook.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    The new and completely revised edition of the Asphalt Handbook, a standard reference work in the field of asphalt technology and construction, summarizes with reference the information contained in other Asphalt Institute technical manuals. Major areas discussed include the following--(1) uses of asphalt, (2) terms relating to asphalt and its…

  15. Evaluation of Warm Mix Asphalt Additives for Use in Modified Asphalt Mixtures

    NASA Astrophysics Data System (ADS)

    Chamoun, Zahi

    The objective of this research effort is to evaluate the use of warm-mix additives with polymer modified and terminal blend tire rubber asphalt mixtures from Nevada and California. The research completed over two stages: first stage evaluated two different WMA technologies; Sasobit and Advera, and second stage evaluated one additional WMA technology; Evotherm. The experimental program covered the evaluation of resistance of the mixtures to moisture damage, the performance characteristics of the mixtures, and mechanistic analysis of mixtures in simulated pavements. In the both stages, the mixture resistance to moisture damage was evaluated using the indirect tensile test and the dynamic modulus at multiple freeze-thaw cycles, and the resistance of the various asphalt mixtures to permanent deformation using the Asphalt Mixture Performance Tester (AMPT). Resistance of the untreated mixes to fatigue cracking using the flexural beam fatigue was only completed for the first stage. One source of aggregates was sampled in, two different batches, three warm mix asphalt technologies (Advera, Sasobit and Evotherm) and three asphalt binder types (neat, polymer-modified, and terminal blend tire rubber modified asphalt binders) typically used in Nevada and California were evaluated in this study. This thesis presents the resistance of the first stage mixtures to permanent deformation and fatigue cracking using two warm-mix additives; Advera and Sasobit, and the resistance to moisture damage and permanent deformation of the second stage mixtures with only one warm-mix additive; Evotherm.

  16. Road asphalt modifiers based on oil-resistant rubbers and products of thermal transformations of coals

    SciTech Connect

    Sharypov, V.I.; Kiselev, V.P.; Beregovtsova, N.G.; Bugaenko, M.B.; Kuznetsov, B.N.

    2008-07-15

    The properties of asphalt binder modifiers prepared by dissolving butadiene-acrylonitrile rubbers and their production waste in liquid products of heat treatment of various brands of coal were studied.

  17. 75 FR 13646 - Public Meeting With Interested Persons To Discuss the Proposed AC 20-42D, Hand Fire Extinguishers...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... Federal Aviation Administration Public Meeting With Interested Persons To Discuss the Proposed AC 20-42D... received regarding proposed advisory circular (AC) 20-42D, Hand Fire Extinguishers for use in Aircraft... (IASFPWG) to draft a revision to the current AC 20-42C, issued on March 1984, by incorporating...

  18. A review of the fundamentals of polymer-modified asphalts: Asphalt/polymer interactions and principles of compatibility.

    PubMed

    Polacco, Giovanni; Filippi, Sara; Merusi, Filippo; Stastna, George

    2015-10-01

    During the last decades, the number of vehicles per citizen as well as the traffic speed and load has dramatically increased. This sudden and somehow unplanned overloading has strongly shortened the life of pavements and increased its cost of maintenance and risks to users. In order to limit the deterioration of road networks, it is necessary to improve the quality and performance of pavements, which was achieved through the addition of a polymer to the bituminous binder. Since their introduction, polymer-modified asphalts have gained in importance during the second half of the twentieth century, and they now play a fundamental role in the field of road paving. With high-temperature and high-shear mixing with asphalt, the polymer incorporates asphalt molecules, thereby forming a swallowed network that involves the entire binder and results in a significant improvement of the viscoelastic properties in comparison with those of the unmodified binder. Such a process encounters the well-known difficulties related to the poor solubility of polymers, which limits the number of macromolecules able to not only form such a structure but also maintain it during high-temperature storage in static conditions, which may be necessary before laying the binder. Therefore, polymer-modified asphalts have been the subject of numerous studies aimed to understand and optimize their structure and storage stability, which gradually attracted polymer scientists into this field that was initially explored by civil engineers. The analytical techniques of polymer science have been applied to polymer-modified asphalts, which resulted in a good understanding of their internal structure. Nevertheless, the complexity and variability of asphalt composition rendered it nearly impossible to generalize the results and univocally predict the properties of a given polymer/asphalt pair. The aim of this paper is to review these aspects of polymer-modified asphalts. Together with a brief description of

  19. A review of the fundamentals of polymer-modified asphalts: Asphalt/polymer interactions and principles of compatibility.

    PubMed

    Polacco, Giovanni; Filippi, Sara; Merusi, Filippo; Stastna, George

    2015-10-01

    During the last decades, the number of vehicles per citizen as well as the traffic speed and load has dramatically increased. This sudden and somehow unplanned overloading has strongly shortened the life of pavements and increased its cost of maintenance and risks to users. In order to limit the deterioration of road networks, it is necessary to improve the quality and performance of pavements, which was achieved through the addition of a polymer to the bituminous binder. Since their introduction, polymer-modified asphalts have gained in importance during the second half of the twentieth century, and they now play a fundamental role in the field of road paving. With high-temperature and high-shear mixing with asphalt, the polymer incorporates asphalt molecules, thereby forming a swallowed network that involves the entire binder and results in a significant improvement of the viscoelastic properties in comparison with those of the unmodified binder. Such a process encounters the well-known difficulties related to the poor solubility of polymers, which limits the number of macromolecules able to not only form such a structure but also maintain it during high-temperature storage in static conditions, which may be necessary before laying the binder. Therefore, polymer-modified asphalts have been the subject of numerous studies aimed to understand and optimize their structure and storage stability, which gradually attracted polymer scientists into this field that was initially explored by civil engineers. The analytical techniques of polymer science have been applied to polymer-modified asphalts, which resulted in a good understanding of their internal structure. Nevertheless, the complexity and variability of asphalt composition rendered it nearly impossible to generalize the results and univocally predict the properties of a given polymer/asphalt pair. The aim of this paper is to review these aspects of polymer-modified asphalts. Together with a brief description of

  20. Evaluation of asphalt-rubber interlayers. (Revised). Final research report, September 1986-September 1992

    SciTech Connect

    Estakhri, C.K.; Pendleton, O.; Lytton, R.L.

    1994-02-01

    The report presents the field performance results of three asphalt-rubber interlayer test roads in terms of the effectiveness of the interlayer at reducing the rate of reflection cracking. Several variables were included in the field experiments: concentration of rubber, binder application rate, type or source of rubber, and digestion (or mixing) time of asphalt and rubber. Control sections were made up of no interlayer and interlayer binders of polymer-modified asphalt and conventional asphalt cement. Results of the statistical analyses of the data indicated that, in general, asphalt-rubber interlayers are more effective at reducing reflection cracking than no interlayer at all. Asphalt-rubber also peerformed better than control sections composed of asphalt cement interlayers and polymer-modified interlayers except in one case where the interlyaer was composed of a double application of asphalt cement/aggregate. The data also indicated that higher binder application rates lead to imnproved cracking resistance; however, on many test sections, excessively high binder application rates caused flushing at the pavement surface.

  1. Asphalt Pavement Aging and Temperature Dependent Properties Using Functionally Graded Viscoelastic Model

    ERIC Educational Resources Information Center

    Dave, Eshan V.

    2009-01-01

    Asphalt concrete pavements are inherently graded viscoelastic structures. Oxidative aging of asphalt binder and temperature cycling due to climatic conditions being the major cause of non-homogeneity. Current pavement analysis and simulation procedures dwell on the use of layered approach to account for these non-homogeneities. The conventional…

  2. Characterization of asphalt and asphalt recyclability

    SciTech Connect

    Painter, P.C.

    1993-10-01

    The goal of the research program was to construct a simple model and computer programs that will allow at least a qualitative understand of the phase behavior of asphalt (i.e., how asphalt components mix with one another), mixtures of different types of asphalt (i.e., in recycling) and mixtures of asphalt with other materials, such as synthetic polymers. The authors have constructed such a model and computer programs (for Macintosh computers) that allow such calculations to be performed easily.

  3. Recycling of asphalt mixtures containing crumb rubber. Final report, 1 September 1994-30 August 1997

    SciTech Connect

    Ruth, B.E.; Tia, M.; Jonsson, G.; Setze, J.C.

    1997-05-01

    An investigation of the effects of Crumb Rubber Modifier (CRM) on asphalt binder and mixture properties was conducted to determine whether or not CRM would have a detrimental effect on the properties of recycled paving mixtures containing CRM RAP. Although CRM increased the viscosity and lowered the temperature susceptibility of the binder, the effect was not pronounced at CRM of 12 percent or less. Recycled structural asphalt mixtures containing 50 percent RAP with 12 percent CRM had essentially the same shear strength and air void content properties as a conventional asphalt mixture without any CRM. However, mixtures containing 18 percent or more CRM could have different properties which may affect recycling operations.

  4. Review of crumb-rubber modified asphalt concrete technology. Final research report

    SciTech Connect

    Papagiannakis, A.T.; Lougheed, T.J.

    1995-11-01

    This study presents an analysis of the characteristics of crumb-rubber modified (CRM) asphalt pavements. It is comprised of a state-of-the-art literature review and laboratory testing conducted with a Brookfield viscometer. The reaction that occurs between the rubber and asphalt is not a chemical reaction, but rather a diffusion process that includes the physical absorption of aromatic oils from the asphalt into the polymer chain of the rubber. The presence of CRM in asphalt produces a thicker binder, which increases aging and oxidation resistance. The presence of carbon black in CRM improves binder durability. The temperature susceptibility of the mix is reduced, causing more uniform fatigue characteristics. CRM applications have been met with various degrees of success because existing quality control and quality assurance methods have not been developed enough to ensure desired binder properties in the field.

  5. Performance evaluation of high modulus asphalt concrete mixes

    NASA Astrophysics Data System (ADS)

    Haritonovs, V.; Tihonovs, J.; Zaumanis, M.

    2016-04-01

    Dolomite is one of the most available sedimentary rocks in the territory of Latvia. Dolomite quarries contain about 1000 million tons of this material. However, according to Latvian Road Specifications, this dolomite cannot be used for average and high intensity roads because of its low quality (mainly, LA index). Therefore, mostly imported magmatic rocks (granite, diabase, gabbro, basalt) or imported dolomite are used which makes asphalt expensive. However, practical experience shows that even with these high quality materials roads exhibit rutting, fatigue and thermal cracks. The aim of the research is to develop a high performance asphalt concrete for base and binder courses using only locally available aggregates. In order to achieve resistance against deformations at a high ambient temperature, a hard grade binder was used. Workability, fatigue and thermal cracking resistance, as well as sufficient water resistance is achieved by low porosity (3-5%) and higher binder content compared to traditional asphalt mixtures. The design of the asphalt includes a combination of empirical and performance based tests, which in laboratory circumstances allow simulating traffic and environmental loads. High performance AC 16 base asphalt concrete was created using local dolomite aggregate with polymer modified (PMB 10/40-65) and hard grade (B20/30) bitumen. The mixtures were specified based on fundamental properties in accordance to EN 13108-1 standard.

  6. Reinforcement of asphalt concrete pavement by segments of exhausted fiber used for sorption of oil spill

    NASA Astrophysics Data System (ADS)

    Lukashevich, V. N.; Efanov, I. N.

    2015-01-01

    The paper is aimed at construction of the experimental road pavement made of dispersed reinforced asphalt concrete. Electronic paramagnetic resonance, infrared spectroscopy and fluorescent bitumen studies were used to prove that disperse reinforcement of asphalt concrete mixtures with fibers of exhausted sorbents reduce the selective filtration of low polymeric fractions of petroleum bitumen and improve its properties in the adsorption layer. Sesquioxides are neutralized as catalysts aging asphalt binder. This leads to improvement in the elasticity of bitumen films at low temperatures and provide better crack resistance of coatings to reduce the intensity of the aging of asphalt binder, and, therefore, to increase the durability of road pavements. The experimental road pavement made of dispersed reinforced asphalt concrete operated during 4 years and demonstrated better transport- performance properties in comparison with the analogue pavements.

  7. Rubberized asphalt emulsion

    SciTech Connect

    Wilkes, E.

    1986-09-02

    A method is described of making a rubberized asphalt composition which comprises the steps of: (a) combining asphalt with a hydrocarbon oil having a flash point of 300/sup 0/F. or more to provide a homogenous asphalt-oil mixture or solution, (b) then combining the asphalt-oil mixture with a particulate rubber at a temperature sufficient to provide a homogenous asphalt-rubber-oil gel, and (c) emulsifying the asphalt-rubber-oil gel by passing the gel, water, and an emulsifying agent through a colloid mill to provide an emulsion.

  8. Investigation of mineral filler effects on the aging process of asphalt mastics

    NASA Astrophysics Data System (ADS)

    Moraes, Raquel

    Aging of asphalt binders is induced by chemical and/or physicochemical changes during production of pavement and throughout its service life. Although binder aging in pavement always occurs while binder is in contact with aggregates and mineral filler, in most laboratory aging studies, and in current specifications, asphalt binders are individually aged without accounting for aggregate induced interactions. Past research has had conflicting findings, attributing both mitigating and/or catalytic effects to the presence of mineral filler in asphalt binder with regards to oxidative aging. Thus, in the present study it was hypothesized that evaluation of asphalt oxidative aging without regard to interactive effect of the presence of mineral filler is inadequate as a specification tool. Effects of mineral fillers on oxidative aging of asphalt is investigated by means of accelerated aging of mastics (asphalt and fillers) in Pressure Aging Vessel (PAV). Testing matrix included aging evaluation of mastics containing different fillers content, mineralogy, and surface area. Results showed that low-temperature behavior of aged mastic can be modified by controlling filler concentration and type. Fillers acts as an agent adsorbing heavy fractions of asphalt binder, therefore reducing stiffness and changing glass-transition temperature. Also, during oxidative aging of asphalt binders and mastics, both diffusion and adsorption mechanisms play a role in the rate of aging of asphaltic material. A method to characterize the behavior of mastics with aging was also developed by monitoring the mastics |G*| aging index (ratio of complex modulus before and after aging). Gel Permeation Chromatography (GPC) testing results supported mentioned findings regarding |G*| changes, as the presence of mineral filler appears to decelerate the rate of production of larger molecular size oxidation products in the binder phase of mastics. Implication of the findings is that change in molecular size

  9. Metal-phosphate binders

    SciTech Connect

    Howe, Beth Ann; Chaps-Cabrera, Jesus Guadalupe

    2009-05-12

    A metal-phosphate binder is provided. The binder may include an aqueous phosphoric acid solution, a metal-cation donor including a metal other than aluminum, an aluminum-cation donor, and a non-carbohydrate electron donor.

  10. Multiscale Constitutive Modeling of Asphalt Concrete

    NASA Astrophysics Data System (ADS)

    Underwood, Benjamin Shane

    found that the maximum aggregate size of the FAM is mixture dependent, but consistent with a gradation parameter from the Baily Method of mixture design. Mechanistic modeling of these different length scales reveals that although many consider asphalt concrete to be a LVE material, it is in fact only quasi-LVE because it shows some tendencies that are inconsistent with LVE theory. Asphalt FAM and asphalt mastic show similar nonlinear tendencies although the exact magnitude of the effect differs. These tendencies can be ignored for damage modeling in the mixture and FAM scales as long as the effects are consistently ignored, but it is found that they must be accounted for in mastic and binder damage modeling. The viscoelastic continuum damage (VECD) model is used for damage modeling in this research. To aid in characterization and application of the VECD model for cyclic testing, a simplified version (S-VECD) is rigorously derived and verified. Through the modeling efforts at each scale, various factors affecting the fundamental and engineering properties at each scale are observed and documented. A microstructure association model that accounts for particle interaction through physico-chemical processes and the effects of aggregate structuralization is developed to links the moduli at each scale. This model is shown to be capable of upscaling the mixture modulus from either the experimentally determined mastic modulus or FAM modulus. Finally, an initial attempt at upscaling the damage and nonlinearity phenomenon is shown.

  11. Asphalt coking method

    SciTech Connect

    Bonilla, J.A.; Elliott, J.D.

    1987-08-11

    A process is described for treating a heavy hydrocarbon fluid containing asphaltenes comprising: contacting the heavy hydrocarbon fluid with a solvent, wherein the solvent is light naphtha, C/sub 4/ hydrocarbons, C/sub 5/ hydrocarbons, C/sub 6/ hydrocarbons, or a mixture of any of light naphtha and C/sub 4/, C/sub 5/ and C/sub 6/ hydrocarbons, to obtain an asphalt mix, containing asphalt and the solvent, and deasphalted oil mix, containing deasphalted oil and the solvent; feeding the asphalt mix to a delayed coking process to form coke, wherein the asphalt mix is heated by passing the asphalt mix through conduit means in a heater in the delayed coking process. The flow of the asphalt mix through the conduit means is assisted by vaporization in the heater of the solvent in the asphalt mix, and the asphalt mix includes sufficient solvent to provide a residence time of the asphalt mix in the heater adequate for heating the asphalt mix for coking while reducing the formation of coke in the heater; separating the solvent in the deasphalted oil mix from the deasphalted oil mix to yield deasphalted oil; and recovering the deasphalted oil, bypassing the delayed coking process.

  12. Elimination chemistry in asphalt

    SciTech Connect

    Boucher, J.L.; Ihsiung Wang; Martinez, D.F. )

    1990-07-01

    Elimination chemistry provides important information, not only about the chemical properties of asphalt, but also the chemical modification method of asphalt. The chemical reactions which use the natural abundance of radicals are important for free-radical halogenation reaction. Spectral data demonstrates the formation of halogenated asphalt. The utility of dehydrohalogenation modified asphalt is limited. However, the resulting dehydrohalogenation modified asphalt does produce a significant unsaturated intermediate, which can incorporate elastomeric polymers (and monomers) via condensation or addition process. The second chemical modification method is the Hofmann elimination reaction, which was performed by reaction of methyl iodide with asphalt, followed by treatment of base. Spectroscopic data shows that a methyl group attached to nitrogen or sulfur in asphalt after Hofmann elimination reaction. Physical data shows that the Hofmann elimination modification improved the quality of asphalt, such as low temperature susceptibility measured by PVN. The modified asphalt also studied by HP-GPC in order to correlate their physical properties. The result shows that the molecular size distribution has changed and reduced the amount of LMS. The amount of decreasing LMS is also dependent on the content of nitrogen and sulfur in asphalts.

  13. Use of pyrolyzed carbon black as additive in hot mix asphalt

    SciTech Connect

    Park, T.; Lee, K.; Salgado, R.; Lovell, C.W.; Coree, B.J.

    1997-11-01

    This paper deals with the performance of mixtures of asphalt, pyrolyzed carbon black (CB{sub p}), and two aggregates (limestone and slag). Marshall mix design was performed to determine the optimum binder content at 5% of air voids. The range of the optimum binder content was 4.2%--5.5% for limestone mixtures and 6.3%--7.8% for slag mixtures, respectively. Dynamic confined creep tests, gyratory tests, resilient modulus tests, indirect tensile tests, and Hamburg wheel tracking tests were carried out using mixtures at the optimum binder content. The test results indicate that the use of CB{sub p} in asphalt pavements increases Marshall stability, decreases permanent strain, decreases the mix strain rate at 50 C and 138 kPa confinement, increases resilient modulus and tensile strength, and increases the stripping inflection point. These results suggest that CB{sub p} improves asphalt pavement performance.

  14. Incorporation de particules de bardeaux d'asphalte de postconsommation dans les enrobes bitumineux

    NASA Astrophysics Data System (ADS)

    Malo, Jean-Michel

    Every year, more than 200 000 tons of used residential roofing asphalt shingles are sent to landfills in Quebec. In order to reduce this amount, a research project funded by the 3RMCDQ and RECYC-QUÉBEC is ongoing at the LCMB at École de technologie supérieure (ÉTS) in Montreal. This project studies the feasibility of incorporating tear-off shingles particles in hot mix asphalt which could be used on Quebec roads. Currently, in Quebec, the ministry of Transportation (MTQ), allows the use of 5% of new asphalt shingles (factory reject) in the base course and 3% in the surface course, and tear-off shingles are not allowed. Incorporating new shingles particles is valued notably by the MTQ standardization for a reduction of binder in these mixes. As of now, the MTQ does not have a standard on the use of tear-off shingles, but the subject of experimental boards. The research done at ETS aim to characterize a standard base mix, GB20, and a standard surface mix, ESG-10, that contains tear-off shingles. Mixes containing different percentage of virgin binder were fabricated then tested on compaction capacity, on rutting resistance, on thermal cracking resistance (TSRST) and on complex modulus (E*). The amount of Virgin binder is calculated according to different percentage of effective binder from the shingles. This study has permitted to identify an optimal formula for both types of hot mix asphalt that were tested. Results show that for the standard ESG-10 surface mix, the possible contribution of tear-off asphalt shingles would be about 20%. For the standard GB-20 base mix, no reduction in the virgin binder may be considered for now when 5% of tear-off asphalt shingles are incorporated in the formula mix. In this case, further testing on complex modulus are recommended to obtain meaningful results that will determine if a reduction of the virgin binder would not be favorable.

  15. Sulfur extended asphalt pavement evaluation in the State of Washington: SR 270 highway pavement performance report

    NASA Astrophysics Data System (ADS)

    Mahoney, J. P.; Terrel, R. L.; Cook, J. C.

    1982-11-01

    The placement and performance of sulfur extended asphalt (SEA) paving mixtures at a highway test site (SR 270) near Pullman, Washington is summarized. The mixture and structural designs and construction details are included. This is followed by a discussion of the data collection and analysis accomplished over a three year evaluation period (1979-1982). A major experimental feature of the study was the use of 0.100 (conventional asphalt concrete), 30/70 and 40/60 SEA binder ratios (sulfur/asphalt ratios are expressed as weight percents in the experimental paving mixtures.

  16. Characterization of asphalt materials containing bio oil from michigan wood

    NASA Astrophysics Data System (ADS)

    Mills-Beale, Julian

    The objective of this research is to develop sustainable wood-blend bioasphalt and characterize the atomic, molecular and bulk-scale behavior necessary to produce advanced asphalt paving mixtures. Bioasphalt was manufactured from Aspen, Basswood, Red Maple, Balsam, Maple, Pine, Beech and Magnolia wood via a 25 KWt fast-pyrolysis plant at 500 °C and refined into two distinct end forms - non-treated (5.54% moisture) and treated bioasphalt (1% moisture). Michigan petroleum-based asphalt, Performance Grade (PG) 58-28 was modified with 2, 5 and 10% of the bioasphalt by weight of base asphalt and characterized with the gas chromatography-mass spectroscopy (GC-MS), Fourier Transform Infra-red (FTIR) spectroscopy and the automated flocculation titrimetry techniques. The GC-MS method was used to characterize the Carbon-Hydrogen-Nitrogen (CHN) elemental ratio whiles the FTIR and the AFT were used to characterize the oxidative aging performance and the solubility parameters, respectively. For rheological characterization, the rotational viscosity, dynamic shear modulus and flexural bending methods are used in evaluating the low, intermediate and high temperature performance of the bio-modified asphalt materials. 54 5E3 (maximum of 3 million expected equivalent standard axle traffic loads) asphalt paving mixes were then prepared and characterized to investigate their laboratory permanent deformation, dynamic mix stiffness, moisture susceptibility, workability and constructability performance. From the research investigations, it was concluded that: 1) levo, 2, 6 dimethoxyphenol, 2 methoxy 4 vinylphenol, 2 methyl 1-2 cyclopentandione and 4-allyl-2, 6 dimetoxyphenol are the dominant chemical functional groups; 2) bioasphalt increases the viscosity and dynamic shear modulus of traditional asphalt binders; 3) Bio-modified petroleum asphalt can provide low-temperature cracking resistance benefits at -18 °C but is susceptible to cracking at -24 °C; 3) Carbonyl and sulphoxide

  17. Asphalt in Pavement Maintenance.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    Maintenance methods that can be used equally well in all regions of the country have been developed for the use of asphalt in pavement maintenance. Specific information covering methods, equipment and terminology that applies to the use of asphalt in the maintenance of all types of pavement structures, including shoulders, is provided. In many…

  18. CHLOROPLAST STRUCTURE AND FUNCTION IN ac-20, A MUTANT STRAIN OF CHLAMYDOMONAS REINHARDI

    PubMed Central

    Goodenough, Ursula W.; Levine, R. P.

    1970-01-01

    The fine structure of the ac-20 strain of Chlamydomonas reinhardi is described. Cells grown mixotrophically in the presence of acetate have a highly disordered chloroplast membrane organization and usually lack pyrenoids. Chloroplast ribosome levels are only 5–10% of wild-type levels. Cells grown phototrophically without acetate possess more chloroplast ribosomes and have more normal membrane and pyrenoid organization. Chloroplast ribosome levels rise rapidly when cells are transferred from acetate to minimal medium, whereas membrane reorganization occurs only after a lag. These results, combined with earlier studies of the photosynthetic properties of the mutant strain, suggest that proper membrane organization, Photosystem II activity, and ribulose-1,5-diphosphate carboxylase formation are dependent on the presence of chloroplast ribosomes. Other chloroplast components tested are unaffected by a 10-fold reduction in levels of chloroplast ribosomes. PMID:5415236

  19. Chemical modification of asphalt

    SciTech Connect

    Ju, Ruei Fu.

    1989-01-01

    Desirable properties of asphalt pavements include high stability, flexibility, and durability. In order to achieve these properties, the asphalt should bind well with mineral aggregates and the properties of the resulting asphalt concrete should change as slowly as possible during service life. The interaction of water and asphaltic concrete under particular circumstances may cause stripping or loss of adhesion and consequential detachment of the asphalt from the aggregate. Use of aggregates treated with these polymer emulsions resulted in a much stronger bond at the asphalt-aggregate interface. Scanning electron microscope studies showed that a thin polymer film covers the aggregate surface. Ethylene-vinyl acetate copolymer resin 460, ethylene-vinyl acetate copolymer resin 240, styrene butadiene copolymer, cis-1,4-polybutadiene copolymer, and polyethylene were tested as additives. The effect of these on the resistance to permanent deformation and dynamic stiffness is described in this study. The chemical changes that occurred during weathering were also addressed. The effect of oxidation on aged asphalt was determined by measuring the change in infrared absorption with time of exposure. Antioxidants which are capable of decomposing peroxides were found to extend the durability of the asphalt. By observing the concentration of peroxy radicals during the course of a chemical process as indicated by electron spin resonance peak intensity, it was possible to obtain quantitative information on the interaction of antioxidants with peroxy radicals. Indications were obtained that antioxidants are not effective in reducing the brittleness of asphalt upon aging. The effect of six plasticizers on thermal and mechanical properties of asphalt was studied. In general, use of plasticizers resulted in lowered rigidity, increased ductility and increased toughness. Tricresyl phosphate was the most effective.

  20. Evaluation of the effects of crumb rubber and SBR on rutting resistance of asphalt concrete

    SciTech Connect

    Shih, Chuang-Tsair; Tia, Mang; Ruth, B.E.

    1996-12-31

    This paper presents the results of a study to evaluate the effects of addition of crumb rubber (CR) and styrene-butadiene rubber (SBR) on the rutting resistance of asphalt concrete. These two additives were blended with an AC-20 and an AC-30 grade asphalt cements at different levels of concentrations. These modified and unmodified asphalt blends were tested at intermediate and high temperatures to evaluate their rutting resistance characteristics. They were also used to make Florida type S-I structural surface mixtures. These mixtures were made into Marshall-size specimens by using Gyratory Testing Machine (GTM) equipped with air-roller to compact and density to three compaction levels which simulate three different conditions in the pavement. The FDOT`s (Florida Department of Transportation) Loaded Wheel Tester was also used to evaluate the rutting resistance of these asphalt mixtures. The test results indicate that the modified asphalt mixtures show relatively better rutting resistance and shear resistance as compared with the unmodified asphalt mixtures.

  1. Modelling and laboratory studies on the adhesion fatigue performance for thin-film asphalt and aggregate system.

    PubMed

    Wang, Dongsheng; Yi, Junyan; Feng, Decheng

    2014-01-01

    Adhesion between asphalt and aggregate plays an important role in the performance of asphalt mixtures. A low-frequency adhesion fatigue test was proposed in this paper to study the effect of environment on the asphalt-aggregate adhesion system. The stress-based fatigue model had been utilized to describe the fatigue behavior of thin-film asphalt and aggregate system. The factors influencing the adhesion fatigue performance were also investigated. Experiment results show that asphalt has more important effect on the adhesion performance comparing with aggregate. Basalt, which is regarded as hydrophobic aggregates with low silica content, has better adhesion performance to asphalt binder when compared with granite. The effects of aging on the adhesion fatigue performance are different for PG64-22 and rubber asphalt. Long-term aging is found to reduce the adhesion fatigue lives for rubber asphalt and aggregate system, while the effect of long-term aging for aggregate and PG64-22 binder system is positive. Generally the increased stress amplitude and test temperature could induce greater damage and lead to less fatigue lives for adhesion test system. PMID:25054187

  2. Modelling and laboratory studies on the adhesion fatigue performance for thin-film asphalt and aggregate system.

    PubMed

    Wang, Dongsheng; Yi, Junyan; Feng, Decheng

    2014-01-01

    Adhesion between asphalt and aggregate plays an important role in the performance of asphalt mixtures. A low-frequency adhesion fatigue test was proposed in this paper to study the effect of environment on the asphalt-aggregate adhesion system. The stress-based fatigue model had been utilized to describe the fatigue behavior of thin-film asphalt and aggregate system. The factors influencing the adhesion fatigue performance were also investigated. Experiment results show that asphalt has more important effect on the adhesion performance comparing with aggregate. Basalt, which is regarded as hydrophobic aggregates with low silica content, has better adhesion performance to asphalt binder when compared with granite. The effects of aging on the adhesion fatigue performance are different for PG64-22 and rubber asphalt. Long-term aging is found to reduce the adhesion fatigue lives for rubber asphalt and aggregate system, while the effect of long-term aging for aggregate and PG64-22 binder system is positive. Generally the increased stress amplitude and test temperature could induce greater damage and lead to less fatigue lives for adhesion test system.

  3. Evaluation of Warm Mix Asphalt Technologies and Recycled Asphalt Pavements in Truckee Meadows, Nevada

    NASA Astrophysics Data System (ADS)

    Diaz Montecino, Cristian

    This study evaluated the properties and laboratory-performance of Hot Mix Asphalt (HMA) and Warm Mix Asphalt (WMA) mixtures with different levels of Recycled Asphalt Pavements (RAP) content: none for control mixtures, around 15% by dry weight of aggregates, and more than 30% by dry weight of aggregates. The rheological properties were evaluated for virgin and recovered RAP asphalt binders. The target amount of RAP in the mixtures was determined by using Blending Charts and Mortar Experiments. The mixtures are design through the guidelines established in Marshall Mix Design Method considering additional modifications for RAP and WMA from Superpave Mix Design. The mixtures are evaluated for their resistance to moisture damage by means of measuring the Dynamic Modulus |E*| after three freeze/thaw cycles and the indirect tensile strength after one and three freeze/thaw cycles. The resistance of the mixtures to permanent deformation was also evaluated by using the Asphalt Mixture Performance Tester (AMPT) to measure the flow number (FN). For this study, it was determined that the resistance to moisture damage decreases as the number of freeze/thaw cycles increases for most of the evaluated mixtures. Mixtures exhibited an increase in dynamic modulus as the RAP percentage increased. A decrease in the resistance to moisture damage was detected with the increase in RAP content for most of the mixtures. HMA mixtures exhibited a better performance in rutting than the WMA mixtures. An increase in rutting resistance was observed with the increase in RAP percentage for HMA mixtures whereas an inconsistent trend was observed for WMA mixtures. Further study is needed to validate the use of the high percentage of RAP in Washoe County.

  4. 78 FR 49318 - Availability of Draft Advisory Circular (AC) 90-106A and AC 20-167A

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... Systems (78 FR 34935-34958) (Docket No.: FAA-2013-0485; Notice No. 1209). AC 90-106A, Enhanced Flight... the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at http://DocketsInfo... Federal Aviation Administration Availability of Draft Advisory Circular (AC) 90-106A and AC 20-...

  5. Supercritical refining of asphalt to produce asphalt recycling agents

    SciTech Connect

    Chaffin, J.M.; Davison, R.R.; Glover, C.J.; Bullin, J.A.

    1995-12-31

    Several asphalts were fractionated using supercritical pentane. These fractions were analyzed and Gel Permeation Chromatography and High Performance Liquid Chromatography and their viscosities were measured. The properties of these fractions vary not only among the fractions of a given asphalt, but also for the same fraction produced from different asphalts. These widely varied fractions previously have been shown to have potential for reblending to produce superior asphalts. This study investigates the potential for using some of the fractions as asphalt recycling agents. A modified SHRP PAV test was conducted on nine recycled asphalts. The aging indices of eight of the recycled asphalts are superior to the aging index of the original asphalt. In addition, two of the blends using industrial supercritical fractions and the three blends using laboratory supercritical fractions have lower aging indices than blends using commercial recycling agents.

  6. The effect of crumb rubber particle size to the optimum binder content for open graded friction course.

    PubMed

    Ibrahim, Mohd Rasdan; Katman, Herda Yati; Karim, Mohamed Rehan; Koting, Suhana; Mashaan, Nuha S

    2014-01-01

    The main objective of this paper is to investigate the relations of rubber size, rubber content, and binder content in determination of optimum binder content for open graded friction course (OGFC). Mix gradation type B as specified in Specification for Porous Asphalt produced by the Road Engineering Association of Malaysia (REAM) was used in this study. Marshall specimens were prepared with four different sizes of rubber, namely, 20 mesh size [0.841 mm], 40 mesh [0.42 mm], 80 mesh [0.177 mm], and 100 mesh [0.149 mm] with different concentrations of rubberised bitumen (4%, 8%, and 12%) and different percentages of binder content (4%-7%). The appropriate optimum binder content is then selected according to the results of the air voids, binder draindown, and abrasion loss test. Test results found that crumb rubber particle size can affect the optimum binder content for OGFC.

  7. Field Performance of Asphalt Pavements with New Technologies in Northern Nevada

    NASA Astrophysics Data System (ADS)

    Faeth, Benjamin Michael

    The Regional Transportation Commission (RTC) of the Washoe Valley Area has been tasked to determine if three advanced asphalt pavement technologies and one modified aggregate gradation are suitable for implementation within Reno, Stead, and Sparks Nevada. This was accomplished through research and test roads and Intersections to determine if Recycled Asphalt Pavement (RAP), Warm Mix Asphalt (WMA), Polymer-Modified Asphalt Binder, and the Type 2-R aggregate gradation were succeeding in their design plans. Over the course of several years the streets being used by RTC to test the technologies are succeeding within their design lifespans, and the Intersections being used to test the Type 2-R aggregate gradation are showing significant resistance to rutting. Due to the roads and Intersections not being more than 10 years old, these conclusions are subject to change over time.

  8. Development of superior asphalt recycling agency: Phase 1, Technical feasibility. Technical progress report

    SciTech Connect

    Bullin, J.A.; Glover, C.J.; Davison, R.R.; Lin, Moon-Sun; Chaffin, J.; Liu, Meng; Eckhardt, C.

    1996-04-01

    About every 12 years, asphalt roads must be reworked, and this is usually done by placing thick layers (hot-mix overlays) of new material on top of failed material, resulting in considerable waste of material and use of new asphalt binder. A good recycling agent is needed, not only to reduce the viscosity of the aged material but also to restore compatibility. Objective is to establish the technical feasibility (Phase I) of determining the specifications and operating parameters for producing high quality recycling agents which will allow most/all the old asphalt-based road material to be recycled. It is expected that supercritical fractionation can be used. The advanced road aging simulation procedure will be used to study aging of blends of old asphalt and recycling agents.

  9. Assessments of low emission asphalt mixtures produced using combinations of foaming agents

    NASA Astrophysics Data System (ADS)

    Mohd Hasan, Mohd Rosli

    The asphalt foaming techniques have been used over the last couple of decades as an alternative to the traditional method of preparing asphalt mixtures. Based on positive feedback from the industry, this study was initiated to explore and evaluate the performance of the Warm Mix Asphalt (WMA) mixture produced through a foaming process using physical and chemical foaming agents, which are ethanol and sodium bicarbonate (NaHCO3), respectively. The success of this project may lead to new theories and provide an environmentally friendly technique to produce asphalt mixtures. This may advance the understanding of the foaming process and improve the performance of WMA to support sustainable development. Theoretically, ethanol can function in the same manner as water but requires less energy to foam due to its lower boiling point, 78°C. During the asphalt foaming process, numerous bubbles were generated by the vaporized ethanol, which significantly increased the volume of the asphalt binder, hence the coating potential of aggregates improves. The sodium bicarbonate was incorporated to enhance the quantity of bubbles and its stability. Therefore, understanding foaming agents, their solubility, chemical reactions, chemical function groups and rheological properties of the foamed binder are essential to help control the foam structure and final properties of the foamed WMA mixture. In order to understand the overall performance of newly developed foaming WMA, this material was evaluated for moisture susceptibility, rutting potential, and resistance to fracture and thermal cracking. The coatability, workability and compactability of foamed asphalt mixtures during production were also evaluated. Based on the results, it was found that the newly proposed foaming WMA has high potential to promote sustainable development by lowering the energy consumption and impacts on the environment. The ethanol is efficient in lowering the viscosity of asphalt binders, enhancing the

  10. State of the practice: Design and construction of asphalt paving materials with crumb-rubber modifier. Final report

    SciTech Connect

    Heitzman, M.A.

    1992-05-01

    The document is a comprehensive overview of the terminology, processes, products, and applications of crumb rubber modifier (CRM) technology. The technology includes any use of scrap tire rubber in asphalt paving materials. In general, CRM technology can be divided into two categories--the wet process and the dry process. When CRM is incorporated into an asphalt paving material, it will modify the properties of the binder (asphalt rubber) and/or act as a rubber aggregate (rubber modified hot mix asphalt). The five concepts for using CRM discussed in the report are McDonald, PlusRide, generic dry, chunk rubber asphalt concrete, and continuous blending asphalt rubber. There are two principal unresolved engineering issues related to the use of CRM in asphalt paving materials. On the national level, the ability to recycle asphalt paving mixes containing CRM has not been demonstrated. At the State and local levels, these modified asphalt mixes must be field evaluated to establish expected levels of performance. The appendices provide guidelines for material specifications, mix design, and construction specifications. An experimental work plan for monitoring performance and a stack emission testing program are also included.

  11. Microbial Degradation of Asphalt1

    PubMed Central

    Phillips, U. A.; Traxler, R. W.

    1963-01-01

    Organisms of the genera Pseudomonas, Chromobacterium, and Bacillus capable of degrading asphalt were isolated by enrichment cultures. The asphalt degradation by these organisms varied from 3 to 25% after incubation for 1 week. The effects of temperature, pH, and atmosphere of incubation on asphalt degradation were investigated and were shown to vary with different organisms on the same substrate. PMID:16349633

  12. Phosphogypsum slag aggregate-based asphaltic concrete mixes

    SciTech Connect

    Foxworthy, P.T.; Nadimpalli, R.S.; Seals, R.K.

    1996-07-01

    Phosphogypsum is a by-product from the production of phosphoric acid used in the fertilizer and chemical industries. Large production rates and problems associated with its stockpiling have led researchers to seek alternative uses for phosphogypsum, primarily as a construction material. One such use is the extraction of sulfur dioxide for the production of sulfuric acid, a process that also generates a by-product slag aggregate. This study investigated the feasibility of using this slag aggregate in asphaltic concrete binder course mixes. The physical properties of the slag aggregate, such as gradation, specific gravity, absorption, unit weight, and void content, were determined, as well as its durability and environmental characteristics. The Marshall mix design method was used to obtain the optimum asphalt content for this aggregate, while moisture susceptibility was examined using the boiling and modified Lottman tests. Indirect tensile, resilient modulus, and dynamic creep tests were performed on the mix to evaluate its performance potential. The results of the study indicate that phosphogypsum-based slag aggregate can be successfully employed in asphaltic concrete binder course mixtures.

  13. Asphalt pavement surfaces and asphalt mixtures. Transportation research record

    SciTech Connect

    1996-12-31

    The papers in this volume, which deal with asphalt pavement surfaces and asphalt mixtures, should be of interest to state and local construction, design, materials, and research engineers as well as contractors and material producers. The papers in Part 1 include discussions of pavement smoothness specifications and skidding characteristics. The first four papers in Part 2 were submitted in response to a call for papers for a session at the 75th Annual Meeting of the Transportation Research Board on low-temperature properties of hot-mix asphalt. The next eight are on the influence of volumetric and strength properties on the performance of hot-mix asphalt. In the following three papers, the topics covered are the complex modulus of asphalt concrete, cold in-place asphalt recycling, and polymer modification of asphalt pavements in Ontario. The last two papers were presented in a session on relationship of materials characterization to accelerated pavement performance testing.

  14. Rutting and Fatigue Cracking Resistance of Waste Cooking Oil Modified Trinidad Asphaltic Materials.

    PubMed

    Maharaj, Rean; Ramjattan-Harry, Vitra; Mohamed, Nazim

    2015-01-01

    The influence of waste cooking oil (WCO) on the performance characteristics of asphaltic materials indigenous to Trinidad, namely, Trinidad Lake Asphalt (TLA), Trinidad Petroleum Bitumen (TPB), and TLA : TPB (50 : 50) blend, was investigated to deduce the applicability of the WCO as a performance enhancer for the base asphalt. The rheological properties of complex modulus (G (∗) ) and phase angle (δ) were measured for modified base asphalt blends containing up to 10% WCO. The results of rheology studies demonstrated that the incremental addition of WCO to the three parent binders resulted in incremental decreases in the rutting resistance (decrease in G (∗) /sinδ values) and increases in the fatigue cracking resistance (decrease in G (∗) sinδ value). The fatigue cracking resistance and rutting resistance for the TLA : TPB (50 : 50) blends were between those of the blends containing pure TLA and TPB. As operating temperature increased, an increase in the resistance to fatigue cracking and a decrease in the rutting resistance were observed for all of the WCO modified asphaltic blends. This study demonstrated the capability to create customized asphalt-WCO blends to suit special applications and highlights the potential for WCO to be used as an environmentally attractive option for improving the use of Trinidad asphaltic materials. PMID:26336652

  15. Rutting and Fatigue Cracking Resistance of Waste Cooking Oil Modified Trinidad Asphaltic Materials

    PubMed Central

    Maharaj, Rean; Ramjattan-Harry, Vitra; Mohamed, Nazim

    2015-01-01

    The influence of waste cooking oil (WCO) on the performance characteristics of asphaltic materials indigenous to Trinidad, namely, Trinidad Lake Asphalt (TLA), Trinidad Petroleum Bitumen (TPB), and TLA : TPB (50 : 50) blend, was investigated to deduce the applicability of the WCO as a performance enhancer for the base asphalt. The rheological properties of complex modulus (G∗) and phase angle (δ) were measured for modified base asphalt blends containing up to 10% WCO. The results of rheology studies demonstrated that the incremental addition of WCO to the three parent binders resulted in incremental decreases in the rutting resistance (decrease in G∗/sinδ values) and increases in the fatigue cracking resistance (decrease in G∗sinδ value). The fatigue cracking resistance and rutting resistance for the TLA : TPB (50 : 50) blends were between those of the blends containing pure TLA and TPB. As operating temperature increased, an increase in the resistance to fatigue cracking and a decrease in the rutting resistance were observed for all of the WCO modified asphaltic blends. This study demonstrated the capability to create customized asphalt-WCO blends to suit special applications and highlights the potential for WCO to be used as an environmentally attractive option for improving the use of Trinidad asphaltic materials. PMID:26336652

  16. Acrylic emulsion as a straw binder in reclaiming coal surface-mined land. Technical note

    SciTech Connect

    Brown, J.E.; Maddox, J.B.; Bartley, G.N. Jr.

    1981-01-01

    This study was designed to test the effectiveness of acrylic emulsion (AE) as a straw binder. A secondary objective was to determine the application cost differences, if any, between the AE and emulsified asphalt. Treatments consisted of: (1) 0.56 kiloliters of AE/hectare plus 2.2 metric tons of straw/hectare, and (2) 1.68 kiloliters of asphalt/hectare plus 4.5 metric tons of straw/hectare. Vegetative cover obtained during two growing seasons with Treatment 1 was as good as that with Treatment 2.

  17. Slow mechanical relaxation in asphalt

    SciTech Connect

    Stastna, J.; Zanzotto, L.

    1996-12-31

    Asphalt (or bitumen) is one of the earliest construction materials used by mankind. However, despite the long history of its use and the important role it plays at the present time, in the construction of pavements, the composition and especially the structure of asphalt is still not fully understood. It is generally believed that asphalt is a multiphase system in which the large and polar molecules called asphaltenes, or their agglomerates are dispersed in the medium consisting of the smaller molecules with low or no polarity. Opinions on how the asphalt structure is arranged vary. The study of asphalt structure is made extremely difficult by the nature of this material. Non-invasive methods such as dynamic mechanical or electric testing, which investigate the asphalt in its original state may greatly contribute to our knowledge of the asphalt internal structure.

  18. Development of asphalts and pavements using recycled tire rubber. Phase 1, Technical feasibility. Technical progress report, September 1, 1994--August 31, 1995

    SciTech Connect

    Bullin, J.A.; Davison, R.R.; Glover, C.J.

    1996-06-01

    About 285 million tires are discarded every year; less than 100 million are currently being recycled, with the rest being placed in landfills and other waste sites. A solution to reduce the littering of the environment is to use ground tire rubber in road construction. Currently, about 27 million tons of asphalt are used each year in road construction and maintenance of the country`s 2 million miles of roads. If all of the waste tire rubber could be combined with asphalt in road construction, it would displace less than 6% of the total asphalt used each year, yet could save about 60 trillion Btus annually. Purpose of this project is to provide data needed to optimize the performance of rubber-asphalt concretes. The first phase is to develop asphalts and recycling agents tailored for compatibility with ground tire rubber. Chapter 2 presents results on Laboratory Testing and Evaluation: fractionate asphalt material, reblending for aromatic asphalts, verifying optimal curing parameters, aging of blends, and measuring ductilities of asphalt-rubber binders. Chapter 3 focuses on Evaluating Mixture Characteristics (modified binders). Chapter 4 covers Adhesion Test Development (water susceptibility is also covered). The final chapter focuses on the Performance/Economic Update and Commercialization Plan.

  19. Development of superior asphalt recycling agents. Phase 1, Technical feasibility. Technical progress report

    SciTech Connect

    Bullin, J.A.; Glover, C.J.; Davison, R.R.; Chaffin, J.; Lin, Moon-Sun

    1995-07-01

    About 27 million tons of asphalt and nearly twenty times this much aggregate are consumed each year to build and maintain over two million miles of roads in this country. Over a cycle of about 12 years on the average, these roads must be reworked and much of these millions of tons of rock and asphalt cannot be reused with present recycling technology. Instead, much of the maintenance is accomplished by placing thick layers (hot-mix overlays) of new material on top of the failed material. This results in considerable waste of material, both in terms of quality aggregate and in terms of asphalt binder. In addition, the new asphalt binder represents a significant source of potential energy. The main impediment to recycling asphalt binder is the poorly developed science of recycling agent composition and, as a result, optimum recycling agents are not available. An excellent recycling agent should not only be able to reduce the viscosity of the aged material, but it must also be able to restore compatibility. The properties of the old material and recycling agent must be compatible to give both good initial properties and aging characteristics, and this must be understood. The agent must also be inexpensive and easily manufactured. A large quantity of potential feedstock for the production of recycling agents is available and much of it is now fed to cokers. This material could be recovered by supercritical extraction which is an existing refinery technology. A supercritical pilot plant is available at Texas A&M and has been used to produce fractions for study. The objective of this research is to establish the technical feasibility of determining the specifications and operating parameters necessary to produce high quality recycling agents which will allow most old asphalt-based road material to be recycled.

  20. Discovery with "Binders".

    ERIC Educational Resources Information Center

    Candler, W. J.

    1981-01-01

    It is helpful to elicit sentences using "binders" and to examine their properties together, especially when the indigenous language has textual and logical processes different from those of English. Such a procedure increases students' awareness of the delicacy of the clause/sentence grammar which pivots around these difficult words. (Author)

  1. Time dependent viscoelastic rheological response of pure, modified and synthetic bituminous binders

    NASA Astrophysics Data System (ADS)

    Airey, G. D.; Grenfell, J. R. A.; Apeagyei, A.; Subhy, A.; Lo Presti, D.

    2016-08-01

    Bitumen is a viscoelastic material that exhibits both elastic and viscous components of response and displays both a temperature and time dependent relationship between applied stresses and resultant strains. In addition, as bitumen is responsible for the viscoelastic behaviour of all bituminous materials, it plays a dominant role in defining many of the aspects of asphalt road performance, such as strength and stiffness, permanent deformation and cracking. Although conventional bituminous materials perform satisfactorily in most highway pavement applications, there are situations that require the modification of the binder to enhance the properties of existing asphalt material. The best known form of modification is by means of polymer modification, traditionally used to improve the temperature and time susceptibility of bitumen. Tyre rubber modification is another form using recycled crumb tyre rubber to alter the properties of conventional bitumen. In addition, alternative binders (synthetic polymeric binders as well as renewable, environmental-friendly bio-binders) have entered the bitumen market over the last few years due to concerns over the continued availability of bitumen from current crudes and refinery processes. This paper provides a detailed rheological assessment, under both temperature and time regimes, of a range of conventional, modified and alternative binders in terms of the materials dynamic (oscillatory) viscoelastic response. The rheological results show the improved viscoelastic properties of polymer- and rubber-modified binders in terms of increased complex shear modulus and elastic response, particularly at high temperatures and low frequencies. The synthetic binders were found to demonstrate complex rheological behaviour relative to that seen for conventional bituminous binders.

  2. Assessment of asphalt mixtures characteristics through GPR testing

    NASA Astrophysics Data System (ADS)

    Pais, Jorge; Fernandes, Francisco

    2014-05-01

    Road pavements are composed by granular and asphalt layers, placed over the pavement subgrade, which are designed to resist to traffic and climatic effects. Pavement distresses include permanent deformation mainly due to the contribution of the subgrade and fatigue cracking in the asphalt layers. Fatigue cracking is the main pavement distress and is responsible for the main rehabilitations carried out in road pavements which leads, in most cases, to the pavement reconstruction due to the severity of the cracking observed in many roads. For a given aggregate gradation, the fatigue cracking resistance is related to the proportions of the components in the asphalt mixtures, namely the void content and the binder content. Also the presence of water, or moisture, has an important influence in the fatigue resistance, and its effect is characterized by a reduction in the fatigue cracking resistance. The characteristics of the asphalt mixtures applied in road pavements can be assessed in laboratory through the testing of cores extracted from the pavement. These cores are extracted some representative section of the pavement, usually equally spaced in the road. Due to the construction process, the representative sections of the pavement don't allow to identify the quality of the whole pavement. Thus, the use of continuous measurement is essential to ensure the perfect assessment of the pavement quality and the use of the GPR assumes a paramount importance. Thus, this communication presents several GPR tests carried out on pavement slabs produced in laboratory with different void content, binder content and moisture content in order to establish different classifiers that will allow the identification of this condition during regular inspections. Furthermore, tests carried on specimens before and after fatigue tests will allow to calculate similar parameters to estimate the state of conservation of pavements in terms of stiffness and the presence of cracks. This work is a

  3. A review of changes in composition of hot mix asphalt in the United States.

    PubMed

    Mundt, Diane J; Marano, Kristin M; Nunes, Anthony P; Adams, Robert C

    2009-11-01

    This review researched the materials, methods, and practices in the hot mix asphalt industry that might impact future exposure assessments and epidemiologic research on road paving workers. Since World War II, the U.S. interstate highway system, increased traffic volume, transportation speeds, and vehicle axle loads have necessitated an increase in demand for hot mix asphalt for road construction and maintenance, while requiring a consistent road paving product that meets state-specific physical performance specifications. We reviewed typical practices in hot mix asphalt paving in the United States to understand the extent to which materials are and have been added to hot mix asphalt to meet specifications and how changes in practices and technology could affect evaluation of worker exposures for future research. Historical documents were reviewed, and industry experts from 16 states were interviewed to obtain relevant information on industry practices. Participants from all states reported additive use, with most being less than 2% by weight. Crumb rubber and recycled asphalt pavement were added in concentrations approximately 10% per unit weight of the mix. The most frequently added materials included polymers and anti-stripping agents. Crumb rubber, sulfur, asbestos, roofing shingles, slag, or fly ash have been used in limited amounts for short periods of time or in limited geographic areas. No state reported using coal tar as an additive to hot mix asphalt or as a binder alternative in hot mix pavements for high-volume road construction. Coal tar may be present in recycled asphalt pavement from historical use, which would need to be considered in future exposure assessments of pavers. Changes in hot mix asphalt production and laydown emission control equipment have been universally implemented over time as the technology has become available to reduce potential worker exposures. This work is a companion review to a study undertaken in the petroleum refining

  4. Construction of an experimental sulfur-extended-asphalt pavement

    NASA Astrophysics Data System (ADS)

    Dodge, K. S.

    1982-07-01

    The design, placement and collection of initial data from a sulfur extended asphalt (SEA) pavement and a conventional pavement used as a control is documented. The SEA pavement used 30 percent sulfur by total weight of the binder. Mix temperatures, hot bin gradations, and toxic emissions were monitored at the plant and the site throughout placement. Aggregates were collected from the hot bin during production of the control and SEA mixes for use in a Marshall mix design. Cores were extracted from both SEA and control pavements 1 month after placement for laboratory testing. Pavement surface properties were also examined after 1 month of service.

  5. Laboratory evaluation of selected tar sand asphalts

    SciTech Connect

    Button, J.W.; Epps, J.A.; Gallaway, B.M.

    1980-12-01

    Three tar sand asphalts of similar grades prepared from one syncrude by three different refining methods were characterized by tests commonly used to specify paving asphalts together with certain special tests. Asphalt-aggregate mixtures were prepared using these asphalts and tested in the laboratory to determine strength stiffness stability, tensile properties, temperature effects and water susceptibility. Comparison of the tar sand asphalt properties to conventional petroleum asphalt properties reveal no striking differences.

  6. Asphalt recycle plant and method

    SciTech Connect

    Brashears, D. F.; Butler, T. G.; Elliott, E. J.

    1984-10-16

    An asphalt recycling system and process are incorporated into an existing batch type asphalt plant. The existing asphalt plant has an aggregate dryer and air discharge ducts connected to a filtering system. A recycling dryer has input ducts connected to the existing aggregate dryer discharge ducts and output ducts connected from the recycling dryer back to the existing ducts to the filtering system. A recycle feeder bin for feeding reclaimed asphalt pavement to the recycle dryer is connected to the recycle dryer. A recycle booster burner is operatively connected to the recycle dryer through the input duct to the dryer for providing additional heat to the recycle dryer so that the waste heat from the existing aggregate dryer and the booster burner provide a predetermined heat to the recycle dryer for heating the asphalt material. A recycling storage bin or silo is connected to receive the heated recycled asphalt from the recycle dryer. A hammermill or other means may be provided for breaking up the old asphaltic materials, such as old paving materials prior to entry of the material into the recycle dryer. Dampers are provided for directing heated gases from the existing batch type asphalt plant to the recycling system, as needed, and temperature controls are utilized to control the recycled booster burner to provide the right combination of existing waste and added heat for the recycled dryer. The stored recycled asphalt materials may be fed to an existing plant batching tower for batching and loading into vehicles.

  7. Asphalt-aggregate interactions in hot recycling. Final report, April 1985-March 1987

    SciTech Connect

    Kiggundu, B.M.; Newman, J.K.

    1987-07-01

    This report summarizes results of an investigation of asphalt-aggregate interactions in hot recycled systems. Materials used in the research included a severe stripping aggregate and a nonstripping aggregate. Both were evaluated using the Lottman 70% retained tensile-strength criteria. Additional materials included a 40/60 RAP new aggregate system, one virgin asphalt, two RAP recovered binders, one modifier or recycling agent, and two blends. The modifier was selected using a recently developed specification involving physical, composition, and solubility properties. Aggregates were evaluated for surface area, bulk composition, water-soluble ions, cation exchange capacity, gradation, and specific gravities. Binders were tested for physical properties and composition properties using a modified Clay-Gel procedure, and compatibility properties using a modified Heithaus procedure.

  8. Advances in alternative cementitious binders

    SciTech Connect

    Juenger, M.C.G.; Winnefeld, F.; Provis, J.L.; Ideker, J.H.

    2011-12-15

    There is a burgeoning interest in the development, characterization, and implementation of alternatives to Portland cement as a binder in concrete. The construction materials industry is under increasing pressure to reduce the energy used in production of Portland cement clinker and the associated greenhouse gas emissions. Further, Portland cement is not the ideal binder for all construction applications, as it suffers from durability problems in particularly aggressive environments. Several alternative binders have been available for almost as long as Portland cement, yet have not been extensively used, and new ones are being developed. In this paper, four promising binders available as alternatives to Portland cement are discussed, namely calcium aluminate cement, calcium sulfoaluminate cement, alkali-activated binders, and supersulfated cements. The history of the binders, their compositions and reaction mechanisms, benefits and drawbacks, unanswered questions, and primary challenges are described.

  9. Polyurethane synthesis reactions in asphalts

    SciTech Connect

    Bukowski, A.; Gretkiewicz, J.

    1982-04-01

    A series of asphalt-polyurethane composites was prepared by means of polyurethane synthesis in asphalt and carried out in melt. The applied materials were asphalts of differentiated group components content, polyester polyols of chain structure from linear to strongly branched, 2,4-tolylene diisocyanate, 4,4-methylenebis(phenyl isocyanate), and tinorganic catalyst. The asphalt components react with isocyanates to a minimal degree. The influence of the applied substrates, temperature, and polyurethane content in the system on the basic kinetic relations characterizing the process is presented. Polyurethane synthesis in asphalts does not differ in a fundamental way from the obtaining of polyurethanes, especially when their content in the composition is significant, 20 wt% and more.

  10. Assessment of the aging level of rejuvenated hot mixed asphalt concrete pavements

    NASA Astrophysics Data System (ADS)

    McGovern, Megan; Buttlar, William G.; Reis, Henrique

    2016-04-01

    The efficacy of asphalt rejuvenator on restoring the properties of oxidatively aged asphalt was tested via a non-collinear ultrasonic subsurface wave mixing technique modified for field use. Longitudinal transducers were mounted on angle wedges to generate subsurface dilatational waves to allow for pavement evaluation when there is only access to one side. Because in the field the asphalt concrete (AC) pavement properties (i.e., ultrasonic velocities and attenuations) are unknown, a pre-determined fixed incident angle (based on the AC mixture type) was used, which allows for practical implementation in the field. Oxidative aged AC specimens were coated with rejuvenator (10% by weight of the binder) and left to dwell for varying amounts of time. Once the dwell time reached the desired amount, the specimen was immediately ultrasonically tested. The frequency ratio, f2/f1, at which the interaction took place and the normalized nonlinear wave generation parameter, β/β0, were recorded and compared against a reference plot. It was observed that the rejuvenator had the effect of restoring the nonlinear properties to those corresponding to a virgin sample after a sufficient amount of dwell time. The ability of the rejuvenator to fully penetrate and act on the binder was observed to be dependent on the porosity and aggregate structure, and thus varied for each specimen. As a result, some portions of the binder were restored to a greater extent than others. This non-uniform nature was captured via the nonlinear ultrasonic technique.

  11. Effects of asphalt rejuvenator on thermal and mechanical properties on oxidized hot mixed asphalt pavements

    NASA Astrophysics Data System (ADS)

    Farace, Nicholas A.; Buttlar, William G.; Reis, Henrique

    2016-04-01

    The utilization of asphalt rejuvenator, and its effectiveness for restoring thermal and mechanical properties was investigated via Disk-shaped Compact Tension (DC(T)) and acoustic emission (AE) testing for determining mechanical properties and embrittlement temperatures of the mixtures. During the DC(T) testing the fracture energies and peak loads were used to measure the resistance of the rejuvenated asphalt to low temperature cracking. The AE testing monitored the acoustic emission activity while the specimens were cooled from room temperature to -40 °C to estimate the temperature at which thermal cracking began (i.e. the embrittlement temperature). First, a baseline response was obtained by obtaining the mechanical and thermal response of virgin HMA samples and HMA samples that had been exposed to oxidative aging for 36 hours at 135°C. The results showed the virgin samples had much higher peak loads and fracture energies than the 36 hours aged samples. Acoustic Emission showed similar results with the virgin samples having embrittlement temperatures 10 °C cooler than the 36 hours aged specimens. Then, overaged for 36 hours specimens were treated different amounts of rejuvenator (10%, 15%, and 20% by weight of binder content) and left to dwell for increased amount of time periods varying from one to eight weeks. It was observed that the AE results showed an improvement of embrittlement temperature with increasing with the dwell times. The 8 weeks specimens had cooler embrittlement temperatures than the virgin specimens. Finally, the low temperature effects on fracture energy and peak load of the rejuvenated asphalt was investigated. Rejuvenator was applied (10% by weight of binder) to specimens aged 36 hours at 135 °C, and the dwell time was varied from 1 to 4 weeks. The results showed that the peak loads were restored to levels of the virgin specimens, and the fracture energies improved to levels beyond that of the virgin specimens. The results also showed a

  12. Laboratory and field evaluation of hot mix asphalt with high contents of reclaimed asphalt pavement

    NASA Astrophysics Data System (ADS)

    Van Winkle, Clinton Isaac

    Currently in Iowa, the amount of RAP materials allowed for the surface layer is limited to 15% by weight. The objective of this project was to develop quality standards for inclusion of RAP content higher than 15% in asphalt mixtures. To meet Superpave mix design requirements, it was necessary to fractionate the RAP materials. Based on the extensive sieve-by-sieve analysis of RAP materials, the optimum sieve size to fractionate RAP materials was identified. To determine if the higher percentage of RAP materials than 15% can be used in Iowa's state highway, three test sections with 30.0%, 35.5% and 39.2% of RAP materials were constructed on Highway 6 in Iowa City. The construction of the field test sections was monitored and the cores were obtained to measure field densities of test sections. Field mixtures collected from test sections were compacted in the laboratory in order to test the moisture sensitivity using a Hamburg Wheel Tracking Device. The binder was extracted from the field mixtures with varying amounts of RAP materials and tested to determine the effects of RAP materials on the PG grade of a virgin binder. Field cores were taken from the various mix designs to determine the percent density of each test section. A condition survey of the test sections was then performed to evaluate the short-term performance.

  13. Binder-injecting rockbolt

    SciTech Connect

    Lane, W.L.; Lewis, D.L.

    1987-04-07

    A rockbolt is described for installation in a bore in the roof of an underground excavation to support the roof, comprising: a sleeve for permanent installation in the bore in the roof, the sleeve having an upper and a lower end and having means only in the upper end of the sleeve for defining at least one outlet port in the sleeve; a central member axially disposed in, and extending substantially the length of the sleeve, and defining an annular chamber in the sleeve; means for introducing binder material into the annular chamber in the sleeve near the lower end, the binder material traveling upwardly in the annular chamber, out the ports in the upper end of the sleeve, and downwardly between the sleeve and the bore wall; means for engaging the sleeve near the lower end to the roof face; means for engaging the sleeve near the upper end to the rock surrounding the bore; and means for tensioning the rockbolt to compress the rock between the upper and lower ends.

  14. Char binder for fluidized beds

    DOEpatents

    Borio, Richard W.; Accortt, Joseph I.

    1981-01-01

    An arrangement that utilizes agglomerating coal as a binder to bond coal fines and recycled char into an agglomerate mass that will have suitable retention time when introduced into a fluidized bed 14 for combustion. The simultaneous use of coal for a primary fuel and as a binder effects significant savings in the elimination of non-essential materials and processing steps.

  15. Rehabilitating asphalt highways

    SciTech Connect

    Butalia, T.S.

    2007-07-01

    Coal fly ash has been used on two Ohio full-depth reclamation projects in Delaware and Warren. The object of the project carried out with the Department of Civil and Environmental Engineering and Geodetic Science at Ohio State University is to demonstrate the effective use of Class fly ash in combination with lime or lime kiln dust in the full depth reclamation of asphalt pavements. The article describes the mixes used for the highway reconstruction of part of Section Line Road Delaware County and of a road in Warren County. During construction the pavement sections were instrumented with several structural and environmental monitoring devices and data is being collected on a quarterly basis. Falling Weight Deflectometer (FWD) tests to measure load defection behaviour, resilient of pavement layers and soil and base structural layer coefficient are being carried out twice a year. It was shown that use of fly ash increased the elastic modulus of base layers. This article first appeared in the Feb/May 2007 issue of Asphalt Contractor. 4 photos.

  16. Implementation and Validation of the Viscoelastic Continuum Damage Theory for Asphalt Mixture and Pavement Analysis in Brazil

    NASA Astrophysics Data System (ADS)

    Nascimento, Luis Alberto Herrmann do

    This dissertation presents the implementation and validation of the viscoelastic continuum damage (VECD) model for asphalt mixture and pavement analysis in Brazil. It proposes a simulated damage-to-fatigue cracked area transfer function for the layered viscoelastic continuum damage (LVECD) program framework and defines the model framework's fatigue cracking prediction error for asphalt pavement reliability-based design solutions in Brazil. The research is divided into three main steps: (i) implementation of the simplified viscoelastic continuum damage (S-VECD) model in Brazil (Petrobras) for asphalt mixture characterization, (ii) validation of the LVECD model approach for pavement analysis based on field performance observations, and defining a local simulated damage-to-cracked area transfer function for the Fundao Project's pavement test sections in Rio de Janeiro, RJ, and (iii) validation of the Fundao project local transfer function to be used throughout Brazil for asphalt pavement fatigue cracking predictions, based on field performance observations of the National MEPDG Project's pavement test sections, thereby validating the proposed framework's prediction capability. For the first step, the S-VECD test protocol, which uses controlled-on-specimen strain mode-of-loading, was successfully implemented at the Petrobras and used to characterize Brazilian asphalt mixtures that are composed of a wide range of asphalt binders. This research verified that the S-VECD model coupled with the GR failure criterion is accurate for fatigue life predictions of Brazilian asphalt mixtures, even when very different asphalt binders are used. Also, the applicability of the load amplitude sweep (LAS) test for the fatigue characterization of the asphalt binders was checked, and the effects of different asphalt binders on the fatigue damage properties of the asphalt mixtures was investigated. The LAS test results, modeled according to VECD theory, presented a strong correlation with

  17. Development of superior asphalt recycling agents. Phase 1, Technical feasibility. Final technical progress report

    SciTech Connect

    Bullin, J.A.; Davison, R.R.; Glover, C.J.; Chaffin, J.; Liu, M.; Madrid, R.

    1997-07-01

    After an introduction and a literature survey in Chap. 1, Chap. 2 describes the tasks, together with objectives and important results obtained for each task throughout the entire project. Chaps. 3 thru 7 detail work in developing a qualitative and quantitative knowledge of asphalt oxidation, composition dependence of asphalt properties, and guidelines for producing superior asphalt binders through composition control. They also detail the development of a kinetic model for asphalt oxidative aging and present an understanding of the composition dependence of asphalt oxidation as well as other performance-related properties. Chaps. 8 and 9 compare the aging performance of recycled blends produced using commercial recycling agents and industrial supercritical fractions as rejuvenating agents. Oxidative aging of the recycled blends were evaluated along with the performance of the recycled blends in terms of the strategic highway research program performance grading procedure. Chap. 10 summarizes the work completed in the areas of processing schemes development, projection updates, and scale-up and commercialization plans.

  18. Effect of Crumb Rubber and Warm Mix Additives on Asphalt Aging, Rheological, and Failure Properties

    NASA Astrophysics Data System (ADS)

    Agrawal, Prashant

    Asphalt-rubber mixtures have been shown to have useful properties with respect to distresses observed in asphalt concrete pavements. The most notable change in properties is a large increase in viscosity and improved low-temperature cracking resistance. Warm mix additives can lower production and compaction temperatures. Lower temperatures reduce harmful emissions and lower energy consumption, and thus provide environmental benefits and cut costs. In this study, the effects of crumb rubber modification on various asphalts such as California Valley, Boscan, Alaska North Slope, Laguna and Cold Lake were also studied. The materials used for warm mix modification were obtained from various commercial sources. The RAF binder was produced by Imperial Oil in their Nanticoke, Ontario, refinery on Lake Erie. A second commercial PG 52-34 (hereafter denoted as NER) was obtained/sampled during the construction of a northern Ontario MTO contract. Some regular tests such as Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR), Multiple Stress Creep Recovery (MSCR) and some modified new protocols such as the extended BBR test (LS-308) and the Double-Edge Notched Tension (DENT) test (LS-299) are used to study, the effect of warm mix and a host of other additives on rheological, aging and failure properties. A comparison in the properties of RAF and NER asphalts has also been made as RAF is good quality asphalt and NER is bad quality asphalt. From the studies the effect of additives on chemical and physical hardening tendencies was found to be significant. The asphalt samples tested in this study showed a range of tendencies for chemical and physical hardening.

  19. A historical review of additives and modifiers used in paving asphalt refining processes in the United States.

    PubMed

    Mundt, Diane J; Adams, Robert C; Marano, Kristin M

    2009-11-01

    The U.S. asphalt paving industry has evolved over time to meet various performance specifications for liquid petroleum asphalt binder (known as bitumen outside the United States). Additives to liquid petroleum asphalt produced in the refinery may affect exposures to workers in the hot mix paving industry. This investigation documented the changes in the composition and distribution of the liquid petroleum asphalt products produced from petroleum refining in the United States since World War II. This assessment was accomplished by reviewing documents and interviewing individual experts in the industry to identify current and historical practices. Individuals from 18 facilities were surveyed; the number of facilities reporting use of any material within a particular class ranged from none to more than half the respondents. Materials such as products of the process stream, polymers, elastomers, and anti-strip compounds have been added to liquid petroleum asphalt in the United States over the past 50 years, but modification has not been generally consistent by geography or time. Modifications made to liquid petroleum asphalt were made generally to improve performance and were dictated by state specifications.

  20. Method Of Characterizing An Electrode Binder

    DOEpatents

    Cocciantelli, Jean-Michel; Coco, Isabelle; Villenave, Jean-Jacques

    1999-05-11

    In a method of characterizing a polymer binder for cell electrodes in contact with an electrolyte and including a current collector and a paste containing an electrochemically active material and said binder, a spreading coefficient of the binder on the active material is calculated from the measured angle of contact between standard liquids and the active material and the binder, respectively. An interaction energy of the binder with the electrolyte is calculated from the measured angle of contact between the electrolyte and the binder. The binder is selected such that the spreading coefficient is less than zero and the interaction energy is at least 60 mJ/m.sup.2.

  1. Multiscale imaging and characterization of the effect of mixing temperature on asphalt concrete containing recycled components.

    PubMed

    Cavalli, M C; Griffa, M; Bressi, S; Partl, M N; Tebaldi, G; Poulikakos, L D

    2016-10-01

    When producing asphalt concrete mixture with high amounts of reclaimed asphalt pavement (RAP), the mixing temperature plays a significant role in the resulting spatial distribution of the components as well as on the quality of the resulting mixture, in terms of workability during mixing and compaction as well as in service mechanical properties. Asphalt concrete containing 50% RAP was investigated at mixing temperatures of 140, 160 and 180°C, using a multiscale approach. At the microscale, using energy dispersive X-ray spectroscopy the RAP binder film thickness was visualized and measured. It was shown that at higher mixing temperatures this film thickness was reduced. The reduction in film thickness can be attributed to the loss of volatiles as well as the mixing of RAP binder with virgin binder at higher temperatures. X-ray computer tomography was used to characterize statistically the distribution of the RAP and virgin aggregates geometric features: volume, width and shape anisotropy. In addition using X-ray computer tomography, the packing and spatial distribution of the RAP and virgin aggregates was characterized using the nearest neighbour metric. It was shown that mixing temperature may have a positive effect on the spatial distribution of the aggregates but did not affect the packing. The study shows a tendency for the RAP aggregates to be more likely distributed in clusters at lower mixing temperatures. At higher temperatures, they were more homogeneously distributed. This indicates a higher degree of blending both at microscale (binder film) and macroscale (spatial distribution) between RAP and virgin aggregates as a result of increasing mixing temperatures and the ability to quantify this using various imaging techniques. PMID:27148703

  2. Multiscale imaging and characterization of the effect of mixing temperature on asphalt concrete containing recycled components.

    PubMed

    Cavalli, M C; Griffa, M; Bressi, S; Partl, M N; Tebaldi, G; Poulikakos, L D

    2016-10-01

    When producing asphalt concrete mixture with high amounts of reclaimed asphalt pavement (RAP), the mixing temperature plays a significant role in the resulting spatial distribution of the components as well as on the quality of the resulting mixture, in terms of workability during mixing and compaction as well as in service mechanical properties. Asphalt concrete containing 50% RAP was investigated at mixing temperatures of 140, 160 and 180°C, using a multiscale approach. At the microscale, using energy dispersive X-ray spectroscopy the RAP binder film thickness was visualized and measured. It was shown that at higher mixing temperatures this film thickness was reduced. The reduction in film thickness can be attributed to the loss of volatiles as well as the mixing of RAP binder with virgin binder at higher temperatures. X-ray computer tomography was used to characterize statistically the distribution of the RAP and virgin aggregates geometric features: volume, width and shape anisotropy. In addition using X-ray computer tomography, the packing and spatial distribution of the RAP and virgin aggregates was characterized using the nearest neighbour metric. It was shown that mixing temperature may have a positive effect on the spatial distribution of the aggregates but did not affect the packing. The study shows a tendency for the RAP aggregates to be more likely distributed in clusters at lower mixing temperatures. At higher temperatures, they were more homogeneously distributed. This indicates a higher degree of blending both at microscale (binder film) and macroscale (spatial distribution) between RAP and virgin aggregates as a result of increasing mixing temperatures and the ability to quantify this using various imaging techniques.

  3. 7 CFR 3201.77 - Asphalt restorers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Asphalt restorers. 3201.77 Section 3201.77... Designated Items § 3201.77 Asphalt restorers. (a) Definition. Products designed to seal, protect, or restore poured asphalt and concrete surfaces. (b) Minimum biobased content. The Federal preferred...

  4. 7 CFR 3201.77 - Asphalt restorers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Asphalt restorers. 3201.77 Section 3201.77... Designated Items § 3201.77 Asphalt restorers. (a) Definition. Products designed to seal, protect, or restore poured asphalt and concrete surfaces. (b) Minimum biobased content. The Federal preferred...

  5. Analysis of the dispersion of air pollutants from a factory Asphalt in Nuevo Vallarta, Nay., Mex

    NASA Astrophysics Data System (ADS)

    Carrillo-Gonzalez, F. M.; Gaitán-Rodríguez, M.; Cornejo-López, V. M.; Morales-Hernández, J. C.

    2013-12-01

    An asphalt factory has operated intermittently near the urban area of Nuevo Vallarta on Banderas Bay, Nayarit, Mex. This factory has emissions that can affect the health of people living in the colonies nearest are Valle Dorado and San Vicente. The dispersion of emissions depends on the wind (sea breeze-land breeze) and the roof of the inversion, these phenomena determined by the density and temperature of the lower layers of the atmosphere. Asphalts are dark colored binder materials, formed by a complex non-volatile hydrocarbon chains and high molecular weight. Asphalts are produced from petroleum, but by a process of evaporation of the volatiles, leaving the asphalt alone. Therefore, the material emitted by the fireplace are mainly low molecular weight hydrocarbons known as polycyclic aromatic hydrocarbons (PAHs). The Emergency Response Guide 2008 developed by various agencies in Canada, U.S. and Mexico mentions that the hydrocarbon gas can have health effects. Animal studies have shown that PAHs can cause harmful effects to the skin, body fluids and some PAHs are carcinogenic. An analysis of the wind field, monthly and seasonal averages for the years 2010 and 2011, recorded in AWS administered by the CEMCO and other stations located near the study area.

  6. Mixture design and performance prediction of rubber-modified asphalt in Ohio. Final report

    SciTech Connect

    Liang, R.Y.

    1997-08-01

    Appropriate disposal of scrap tires has been a major environmental concern over the years, mainly due to potential fire and health hazards associated with uncontrolled stockpiling. Primarily driven by this environmental concern, the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991 has required each State to begin incorporating scrap tire rubber into its asphalt paving materials. Although in the revision of the original ISTEA, the mandate has been eliminated, there remains a language of encouraging the use of crumb rubbers in asphalt paving materials. Ohio Department of Transportation (ODOT) desires to develop the mix design procedure, construction practice, and performance specifications for crumb rubber modified asphalt paving materials. This research was conducted to develop the needed design and construction guidance for meeting the ODOT anticipated needs. Specifically, the objectives of this research encompass the following scope: (1) investigation of the rheological properties of asphalt-rubber binder to determine optimum content of crumb rubber, (2) development of optimum mix design for various applications, including both wet and dry mix processes, (3) characterization of mechanical properties of recommended paving mixtures, including resilient modulus, fatigue cracking behavior, low-temperature thermal cracking resistance, water sensitivity test, incremental creep test and loaded wheel track test, and (4) comparison of performance of selected paving mixes.

  7. The Effect of Crumb Rubber Particle Size to the Optimum Binder Content for Open Graded Friction Course

    PubMed Central

    Ibrahim, Mohd Rasdan; Katman, Herda Yati; Karim, Mohamed Rehan; Koting, Suhana; Mashaan, Nuha S.

    2014-01-01

    The main objective of this paper is to investigate the relations of rubber size, rubber content, and binder content in determination of optimum binder content for open graded friction course (OGFC). Mix gradation type B as specified in Specification for Porous Asphalt produced by the Road Engineering Association of Malaysia (REAM) was used in this study. Marshall specimens were prepared with four different sizes of rubber, namely, 20 mesh size [0.841 mm], 40 mesh [0.42 mm], 80 mesh [0.177 mm], and 100 mesh [0.149 mm] with different concentrations of rubberised bitumen (4%, 8%, and 12%) and different percentages of binder content (4%–7%). The appropriate optimum binder content is then selected according to the results of the air voids, binder draindown, and abrasion loss test. Test results found that crumb rubber particle size can affect the optimum binder content for OGFC. PMID:24574875

  8. Cold in-place recycling characterization framework for single or multiple component binder systems

    NASA Astrophysics Data System (ADS)

    Cox, Benjamin C.

    Cold in-place recycling (CIR) is a pavement rehabilitation technique which has gained momentum in recent years. This momentum is due partly to its economic and sustainability characteristics, which has led to CIR market expansion. When pavement network deterioration is considered alongside increasing material costs, it is not beyond reason to expect demands on CIR to continue to increase. Historically, single component binder (SCB) systems, those with one stabilization binder (or two if the secondary binder dosage is 1% or less), have dominated the CIR market and could be considered the general state of practice. Common stabilization binders are either bituminous or cementitious. Two example SCB systems would be: 1) 3% portland cement, or 2) 3% asphalt emulsion with 1% hydrated lime. While traditional SCB systems have demonstrated positive economic and sustainability impacts, this dissertation focuses on multiple component binder (MCB) systems (bituminous and cementitious combined) which exhibit the potential to provide better overall economics and performance. Use of MCBs has the potential to alleviate SCB issues to some extent (e.g. cracking with cementitious SCBs, rutting with bituminous SCBs). Furthermore, to fairly represent both binders in an MCB system a universal design method which can accommodate multiple binder types is needed. The main objectives of this dissertation are to develop a universal CIR design framework and, using this framework, characterize multiple SCB and MCB systems. Approximately 1500 CIR specimens were tested herein along with approximately 300 asphalt concrete specimens which serve as a reference data set for CIR characterization. A case study of a high-traffic Mississippi CIR project which included cement SCB and emulsion SCB sections is also presented to support laboratory efforts. Individual components needed to comprise a universal design framework, such as curing protocols, were developed. SCB and MCB characterization indicated

  9. Flame retarded asphalt blend composition

    SciTech Connect

    Walters, R.B.

    1987-04-21

    This patent describes a flame retarded asphalt composition consisting essentially of a blend of: (a) thermoplastic elastomer modified bitumen; (b) 20-30 wt % inert filler; (c) 1-20 wt % of at least one halogenated flame retardant; and (d) 1-5 wt % of at least one inorganic phosphorus containing compound selected from the group consisting of ammonium phosphate compounds and red phosphorus.

  10. Electrochemical components employing polysiloxane-derived binders

    DOEpatents

    Delnick, Frank M.

    2013-06-11

    A processed polysiloxane resin binder for use in electrochemical components and the method for fabricating components with the binder. The binder comprises processed polysiloxane resin that is partially oxidized and retains some of its methyl groups following partial oxidation. The binder is suitable for use in electrodes of various types, separators in electrochemical devices, primary lithium batteries, electrolytic capacitors, electrochemical capacitors, fuel cells and sensors.

  11. The oxidation of carbonized binders

    SciTech Connect

    Prokushin, V.N.; Fedoseev, S.D.; Kleimenov, V.V.; Kovaneva, M.A.; Marochkin, E.P.; Smyslov, V.I.; Trapeznikov, N.M.

    1983-01-01

    The oxidation by air of carbonized binders used in the production of carbonaceous materials has been studied by the derivatographic method. The effective activation energies of the process have been calculated. Of the materials investigated, the greatest oxidative resistance was possessed by coke obtained from medium-temperature hard-coal pitch.

  12. Anode binders for electrochemical cells

    SciTech Connect

    Ismail, M.I.

    1986-08-26

    An electrochemical cell is described comprised of an alkaline electrolyte, a manganese dioxide cathode and a gelled anode comprised of mercury amalgamated zinc, a starch graft copolymer gelling agent and a liquid petrolatum binder in amounts between 0.02% to 0.2% by weight thereof.

  13. Road pavers' occupational exposure to asphalt containing waste plastic and tall oil pitch.

    PubMed

    Väänänen, Virpi; Elovaara, Eivor; Nykyri, Erkki; Santonen, Tiina; Heikkilä, Pirjo

    2006-01-01

    Waste plastic (WP) and tall oil pitch (T), which are organic recycled industrial by-products, have been used as a binder with bitumen in stone mastic asphalt (SMA) and asphalt concrete (AC). We compared the exposure over one workday in 16 road pavers participating in a survey at four paving sites, using mixes of conventional asphalt (SMA, AC) or mixes containing waste material (SMA-WPT, AC-WPT). The concentrations of 11 aldehydes in air were 515 and 902 microg m(-3) at the SMA-WPT and AC-WPT worksites, being 3 and 13 times greater than at the corresponding worksites laying conventional asphalt. Resin acids (2-42 microg m(-3)), which are known sensitizers, were detected only during laying of AC-WPT. The emission levels (microg m(-3)) of total particulates (300-500), bitumen fumes (60-160), bitumen vapour (80-1120), naphthalene (0.59-1.2), phenanthrene (0.21-0.32), pyrene (<0.015-0.20), benzo(a)pyrene (<0.01) and the sum of 16 PAHs (polycyclic aromatic hydrocarbons, 1.28-2.00) were similar for conventional and WPT asphalts. The dermal deposition of 16 PAHs on exposure pads (on workers' wrist) was low in all pavers (0.7-3.5 ng cm(-2)). Eight OH-PAH biomarkers of naphthalene, phenanthrene and pyrene exposures were quantified in pre- and post-shift urine specimens. The post-shift concentrations (mean +/- SD, micromol mol(-1) creatinine) of 1- plus 2-naphthol; 1-,2-,3-,4- plus 9-phenanthrol; and 1-hydroxypyrene were, respectively, for asphalt workers: 18.1+/- 8.0, 2.41 +/- 0.71 and 0.66+/- 0.58 (smokers); 6.0+/- 2.3, 1.70+/- 0.72 and 0.27+/- 0.15 (non-smokers); WPT asphalt workers: 22.0+/- 9.2, 2.82+/- 1.11 and 0.76+/- 0.18 (smokers); 6.8+/- 2.6, 2.35+/- 0.69 and 0.46+/- 0.13 (non-smokers). The work-related uptake of PAHs was low in all pavers, although it was significantly greater in smokers than in non-smokers. The WPT asphalt workers complained of eye irritation and sore throat more than the pavers who had a much lower exposure to aldehydes and resin acids.

  14. Method and apparatus for fragmenting asphalt

    SciTech Connect

    Eftefield, L. G.; Simmons, G. P.; Stone, G. L.

    1985-12-24

    A method and apparatus for laterally severing an asphalt layer to form a ribbon, separating the asphalt ribbon from an underlying base, elevating the separated asphalt ribbon, and fracturing the elevated asphalt ribbon by bending same. A cutting member having a leading edge which is insertable between the asphalt ribbon and base provides separation thereof along a lateral line. A ramp and elevating structure elevatingly guide the separated asphalt ribbon into a pair of breaker drums which are rotatable in opposite circumferential directions. Each breaker drum has protruding teeth which are arranged in laterally separated circumferential rows with the teeth in adjacent circumferential rows being preferably arcuately offset. Corresponding circumferential rows on the opposed breaker drums are laterally aligned and the teeth in those rows engage opposite surfaces of the asphalt ribbon during rotation of the breaker drums. The teeth in corresponding rows on the respective breaker drums alternately engage opposite surfaces of the asphalt ribbon at longitudinally spaced locations to bend and fracture the asphalt ribbon by displacing it in generally opposite transverse directions at the engaged locations.

  15. Moisture damage in asphalt concrete. Final report

    SciTech Connect

    Not Available

    1991-10-01

    Information is provided on physical and chemical explanations for moisture damage in asphalt concrete, along with a discussion of current practices and test methods for determining or reducing the susceptibility of various asphalt concrete components and mixtures to such damage. Moisture damage in asphalt concrete is a nationwide problem which often necessitates premature replacement of highway pavement surfaces. The report of the Transportation Research Board describes the underlying physical and chemical phenomena responsible for such damage. Current test methods used to determine the susceptibility of asphalt concretes, or their constituents, to moisture damage are described and evaluated. Additionally, current practices for minimizing the potential for moisture damage are examined.

  16. Nature of the chemical reaction for furfural modified asphalt

    SciTech Connect

    Memon, G.M.; Chollar, B.H.

    1994-12-31

    Three of the most serious problems of asphalt pavements today are rutting, cracking, and susceptibility to moisture damage (stripping). Asphalt manufacturers have been mixing asphalts with polymers to produce polymer-modified asphalts with improved rheological properties. However, the costs for these improved polymer-modified asphalts are almost double that of regular asphalts. FHWA researchers have found that asphalt modified by the chemical, furfural (which is prepared by simple elimination reaction of aldopentoses obtained from oat hulls), exhibited better stripping properties and was less temperature susceptible than the virgin asphalt while costing less than polymer-modified asphalts. This paper discusses the possible structure of the furfural-modified asphalt, data for the virgin and furfural-modified asphalts and their Corbett fractions, data from a model reaction between phenol and furfural, and a possible explanation of this structure based on these data.

  17. Assessment of porous asphalt pavement performance: hydraulics and water quality

    NASA Astrophysics Data System (ADS)

    Briggs, J. F.; Ballestero, T. P.; Roseen, R. M.; Houle, J. J.

    2005-05-01

    derived from that which is entering the stormwater treatment system in the adjacent parking lot. Since the facility is new, parking has been less intensive here, and influent concentrations will be adjusted down accordingly. Several wells have been installed in and around the facility. Screened intervals are at two levels; in the reservoir and beneath the facility. One well in the facility is continually monitored for basic water quality parameters (temperature, specific conductivity, pH, dissolved oxygen) and level, and is also sampled with an automated refrigerated sampler. Grab samples are collected from the other wells as a basis for comparison. Water samples are collected during several storm events and during interstorm periods to assess water quality treatment performance. The samples are analyzed for nutrients, metals, petroleum hydrocarbons, and pathogens. The potential for leaching of pollutants from the asphalt binder will also be assessed during these storm events. Water quality treatment performance is compared to those of several other studies. Updates on spring 2005 data are also included in the presentation.

  18. Twin screw wet granulation: Binder delivery.

    PubMed

    Saleh, Mohammed F; Dhenge, Ranjit M; Cartwright, James J; Hounslow, Michael J; Salman, Agba D

    2015-06-20

    The effects of three ways of binder delivery into the twin screw granulator (TSG) on the residence time, torque, properties of granules (size, shape, strength) and binder distribution were studied. The binder distribution was visualised through the transparent barrel using high speed imaging as well as quantified using offline technique. Furthermore, the effect of binder delivery and the change of screw configuration (conveying elements only and conveying elements with kneading elements) on the surface velocity of granules across the screw channel were investigated using particle image velocimetry (PIV). The binder was delivered in three ways; all solid binder incorporated with powder mixture, 50% of solid binder mixed with powder mixture and 50% mixed with water, all the solid binder dissolved in water. Incorporation of all solid binder with powder mixture resulted in the relatively longer residence time and higher torque, narrower granule size distribution, more spherical granules, weaker big-sized granules, stronger small-sized granules and better binder distribution compared to that in other two ways. The surface velocity of granules showed variation from one screw to another as a result of uneven liquid distribution as well as shown a reduction while introducing the kneading elements into the screw configuration. PMID:25869451

  19. Asphalt Raking. Instructor Manual. Trainee Manual.

    ERIC Educational Resources Information Center

    Laborers-AGC Education and Training Fund, Pomfret Center, CT.

    This packet consists of the instructor and trainee manuals for an asphalt raking course. The instructor manual contains a course schedule for 4 days of instruction, content outline, and instructor outline. The trainee manual is divided into five sections: safety, asphalt basics, placing methods, repair and patching, and clean-up and maintenance.…

  20. EVALUATION OF EMISSIONS FROM PAVING ASPHALTS

    EPA Science Inventory

    The report provides data from pilot-scale measurements of the emissions of specific air pollutants from paving asphalt both with and without recycled crumb rubber additives. The methods used in this work measured emissions from a static layer of asphalt maintained for several hou...

  1. Softening agents for recycling asphalt pavement

    SciTech Connect

    Sawatzky, H.; Clelland, F.I.; Farnand, B.A.; Houde, J. Jr.

    1993-08-10

    An asphaltic composition is described consisting essentially of: comminuted aged asphaltic pavement material; an effective amount, from about 2% to about 15 % by weight of a blend of an agent selected from the group consisting of a soft asphalt cement, a conventional asphalt cement, and a cutback asphalt, with a nitrogen-containing, adhesion-improving, anti-stripping agent comprising a sewage sludge-derived oil, or a fraction thereof, said sewage sludge-derived oil comprising a mixture of saturated aliphatic hydrocarbons, monoaromatic hydrocarbons, diaromatic hydrocarbons, polyaromatic hydrocarbons, polar compounds and basic, pyridene-soluble compounds, having the following elemental chemical composition: nitrogen, about 3.4% to about 5% by weight; oxygen, about 5.8% to about 6.9% by weight; sulfur, about 0.3% to about 0.8% by weight; hydrogen, about 9.7% to about 10.4%, and carbon, about 76.9% to about 79.8%.

  2. BEHAVIOR OF MODEL ASPHALT PAVEMENT CONTAINING A HYDRAULIC, GRADED IRON AND STEEL SLAG BASE-COURSE UNDER REPEATED PLATE-LOADING

    NASA Astrophysics Data System (ADS)

    Yoshida, Nobuyuki; Sugisako, Yasunari

    In this paper, the dynamic response of asphalt pave ment containing a hydraulic, graded iron and steel slag (hereafter called HMS) base-course under repeated plate-loading was investigated using a model asphalt pavement and the influence of hydraulicity on th e pavement behavior was discussed. The model pavement constructed was a 4-layer system consis ting of a dense-graded asphalt mix surface layer, a dense-graded asphalt mix binder-course, a HMS base-course and a Masado (heavily-weathered granitic sand) subgrade. A repeated plate-loading test was carri ed out so as to achieve a resilient state. It is shown that surface resilient deflection decreases as curing progresses and after 90 days, the deflection becomes almost half of the initial. Large horizontal tensile strains develop at the bottoms of binder- and base-course, which decrease significantly with curing. It is indicative that HMS base-course behaves like a stiffer plate resulting in a hard-to-deflect state due to the development of hydraulicity.

  3. Investigation of Primary Causes of Load-Related Cracking in Asphalt Concrete Pavement in North Carolina

    NASA Astrophysics Data System (ADS)

    Park, Hong Joon

    sites with observed bottom-up cracking have higher tensile strain levels at the bottom of the asphalt layer than sites with observed top-down cracking. Extracted binder fatigue test results indicate that binder properties between good and poor sections of a given site are not the result of differences in the binder properties. Hence, other mixture design factors are at work in controlling the site variability in terms of fatigue resistance.

  4. Binder enhanced refuse derived fuel

    DOEpatents

    Daugherty, Kenneth E.; Venables, Barney J.; Ohlsson, Oscar O.

    1996-01-01

    A refuse derived fuel (RDF) pellet having about 11% or more particulate calcium hydroxide which is utilized in a combustionable mixture. The pellets are used in a particulate fuel bring a mixture of 10% or more, on a heat equivalent basis, of the RDF pellet which contains calcium hydroxide as a binder, with 50% or more, on a heat equivalent basis, of a sulphur containing coal. Combustion of the mixture is effective to produce an effluent gas from the combustion zone having a reduced SO.sub.2 and polycyclic aromatic hydrocarbon content of effluent gas from similar combustion materials not containing the calcium hydroxide.

  5. Advanced self-healing asphalt composites in the pavement performance field: mechanisms at the nano level and new repairing methodologies.

    PubMed

    Agzenai, Yahya; Pozuelo, Javier; Sanz, Javier; Perez, Ignacio; Baselga, Juan

    2015-01-01

    In an effort to give a global view of this field of research, in this mini-review we highlight the most recent publications and patents focusing on modified asphalt pavements that contain certain reinforcing nanoparticles which impart desirable thermal, electrical and mechanical properties. In response to the increasing cost of asphalt binder and road maintenance, there is a need to look for alternative technologies and new asphalt composites, able to self-repair, for preserving and renewing the existing pavements. First, we will focus on the self-healing property of asphalt, the evidences that support that healing takes place immediately after the contact between the faces of a crack, and how the amount of healing can be measured in both the laboratory and the field. Next we review the hypothetical mechanisms of healing to understand the material behaviour and establish models to quantify the damage-healing process. Thereafter, we outline different technologies, nanotechnologies and methodologies used for self-healing paying particular attention to embedded micro-capsules, new nano-materials like carbon nanotubes and nano-fibres, ionomers, and microwave and induction heating processes.

  6. Polypropylene - asphalt mixtures for waterproofing membranes

    SciTech Connect

    Italia, P.; Brandolese, E.

    1996-12-31

    In any field of polymer-asphalt mixtures application is extremely important to achieve a very good compatibility between the components in order to improve as much as possible the performances due to the polymer content. In the case of waterproofing membranes application this compatibility reduce, moreover, the amount of polymer required to obtain the best performances. Using the Colloidal Instability Index Ic, as measured by the Iatroscan device, we propose a correlation between asphalt`s chemical characteristics and the polymer minimum amount sufficient to disperse in a stable way the asphalt itself in the polymeric matrix. As a result, through the proposed correlation, with a simple asphalt composition analysis it is possible to predict its performance when mixed with polypropilene. In the paper, beside the description of the Iatroscan analytical technique, we also present a method for determining phase inversion based on optical fluorescence microscopy performed on about 30 different samples of asphalt. We also present the experimental correlation laws between the polymer amount at phase inversion and the asphalt single components content.

  7. Influence of Binder in Iron Matrix Composites

    SciTech Connect

    Shamsuddin, S.; Jamaludin, S. B.; Hussain, Z.; Ahmad, Z. A.

    2010-03-11

    The ability to use iron and its alloys as the matrix material in composite systems is of great importance because it is the most widely used metallic material with a variety of commercially available steel grades [1]. The aim of this study is to investigate the influence of binder in particulate iron based metal matrix composites. There are four types of binder that were used in this study; Stearic Acid, Gummi Arabisch, Polyvinyl alcohol 15000 MW and Polyvinyl alcohol 22000 MW. Six different weight percentage of each binder was prepared to produce the composite materials using powder metallurgy (P/M) route; consists of dry mixing, uniaxially compacting at 750 MPa and vacuum sintering at 1100 deg. C for two hours. Their characterization included a study of density, porosity, hardness and microstructure. Results indicate that MMC was affected by the binder and stearic acid as a binder produced better properties of the composite.

  8. Modeling binder removal in ceramic compacts

    NASA Astrophysics Data System (ADS)

    Incledon, Matthew L.

    Binder is often added to ceramic systems to provide mechanical strength to the green bodies during processing. The binder removal sequence for an individual system is difficult to predict due to the thermal reaction and mass transport of the volatile products. The objective of this work is to use computational methods to predict the kinetics of binder removal as a function of composition, particle size, pore size and tortuosity, temperature, body size and shape, etc.. The model will be used to predict the composition, temperature, and pore pressure as a function of time, position within the body, and heating sequence parameters. This will provide the ability to predict optimum heating sequences that minimize processing time and energy input while avoiding harmful high internal pressures and temperatures. Since there are many binder systems in use, a few specific cases will be considered. TGA (thermogravimetric analysis) of binders will be used to measure kinetics parameters that are inputs for the computational model. A framework will be developed to assess the binder removal sequence for a binder and ceramic system. The input for the model, computed in COMSOL Multiphysics, will be determined through analysis of TGA weight loss data and green body characterization. A set of tools will be presented that assist in the fitting of the TGA data, including the binder degrading into multiple species, higher order reactions, parallel and series reactions, etc.. The use of these ideas and tools will allow the modeler to better predict the heating sequence required for a ceramic and binder system to successfully remove all binder material.

  9. Laboratory simulation of oxidative aging of asphalt

    SciTech Connect

    Memon, G.M.; Chollar, B.H.

    1997-12-31

    The objective of this study was to determine the aging characteristics of asphalt mixes, which were mixed and conditioned at times corresponding to times experienced during field mixing. This objective was accomplished by measuring functional group changes of carbonyl and sulfoxide peak areas through infrared spectroscopy techniques of asphalts extracted from mixes subjected to various laboratory and climatic conditioning procedures. Correlations were attempted between these infrared functional group changes of asphalt samples from laboratory aged mixes and that from a pavement mix obtained through drum dryer plant production. Ratios were taken of these unknown peak areas by dividing them by the area of a peak unchanged by oxidation, i.e., the methyl peak. These ratios were evaluated for asphalt mix samples that had undergone a wide range of treatments (oven heating for 0, 1, 2, 3, and 4 hours). It was observed through the carbonyl group changes of the asphalts that an oven aged period of 2 hours for asphalt mixes was needed to simulate the degree of aging occurring during plant mix production.

  10. Rapid determination of actinides in asphalt samples

    DOE PAGES

    Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.

    2014-01-12

    A new rapid method for the determination of actinides in asphalt samples has been developed that can be used in emergency response situations or for routine analysis If a radiological dispersive device (RDD), Improvised Nuclear Device (IND) or a nuclear accident such as the accident at the Fukushima Nuclear Power Plant in March, 2011 occurs, there will be an urgent need for rapid analyses of many different environmental matrices, including asphalt materials, to support dose mitigation and environmental clean up. The new method for the determination of actinides in asphalt utilizes a rapid furnace step to destroy bitumen and organicsmore » present in the asphalt and sodium hydroxide fusion to digest the remaining sample. Sample preconcentration steps are used to collect the actinides and a new stacked TRU Resin + DGA Resin column method is employed to separate the actinide isotopes in the asphalt samples. The TRU Resin plus DGA Resin separation approach, which allows sequential separation of plutonium, uranium, americium and curium isotopes in asphalt samples, can be applied to soil samples as well.« less

  11. Rapid determination of actinides in asphalt samples

    SciTech Connect

    Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.

    2014-01-12

    A new rapid method for the determination of actinides in asphalt samples has been developed that can be used in emergency response situations or for routine analysis If a radiological dispersive device (RDD), Improvised Nuclear Device (IND) or a nuclear accident such as the accident at the Fukushima Nuclear Power Plant in March, 2011 occurs, there will be an urgent need for rapid analyses of many different environmental matrices, including asphalt materials, to support dose mitigation and environmental clean up. The new method for the determination of actinides in asphalt utilizes a rapid furnace step to destroy bitumen and organics present in the asphalt and sodium hydroxide fusion to digest the remaining sample. Sample preconcentration steps are used to collect the actinides and a new stacked TRU Resin + DGA Resin column method is employed to separate the actinide isotopes in the asphalt samples. The TRU Resin plus DGA Resin separation approach, which allows sequential separation of plutonium, uranium, americium and curium isotopes in asphalt samples, can be applied to soil samples as well.

  12. Effects of reclaimed asphalt pavement on indirect tensile strength test of conditioned foamed asphalt mix

    NASA Astrophysics Data System (ADS)

    Yati Katman, Herda; Rasdan Ibrahim, Mohd; Yazip Matori, Mohd; Norhisham, Shuhairy; Ismail, Norlela

    2013-06-01

    This paper presents the results of Indirect Tensile Strength (ITS) Test for samples prepared with reclaimed asphalt pavement (RAP). Samples were conditioned in water at 25°C for 24 hours prior to testing. Results show that recycled aggregate from reclaimed asphalt pavement performs as well as virgin aggregate.

  13. SITE DEMONSTRATION CAPSULE --MATCON MODIFIED ASPHALT FOR WASTE CONTAINMENT

    EPA Science Inventory

    MatCon is a polymer modified asphalt material designed specifically for waste contaminment applications. The modifications to the material differentiate it from conventional paving asphalt by minimizing the damaging effects of environmental exposure that could detract from the d...

  14. Analysis of asphalt-based roof systems using thermal analysis

    SciTech Connect

    Paroli, R.M.; Delgado, A.H.

    1996-12-31

    Asphalt has been used in the construction of roads and houses for thousands of years. The properties of asphalt has rendered it quite useful in roofing and waterproofing applications. The most popular use of asphalt in industrial roofing is in the form of a built-up roof or modified-bituminous sheet. This type of roof consists of asphalt, reinforcement and aggregate which is used to protect the asphalt from ultraviolet rays. All materials have their weaknesses and asphalt is no exception. A good asphalt (e.g., low asphaltene content) must be used to ensure the quality and low-temperature performance of roofing asphalts. Polymer additives can be added. The objective of this work was to demonstrate the utility of termogravimetry and dynamic mechanical analysis in establishing the durability of modified bituminous membranes.

  15. Effects of preparation process on performance of rubber modified asphalt

    NASA Astrophysics Data System (ADS)

    Liu, Hanbing; Luo, Guobao; Wang, Xianqiang; Jiao, Yubo

    2015-06-01

    The rational utilization of waste rubber tire is essential for the environmental protection. Utilizing rubber particles to modify asphalt can not only improve asphalt performance, but also help the recycling of waste materials. Considering the effect of different preparation process parameters on the performance of rubber modified asphalt, this paper analyzes the effects of the shear temperature, shear time and shear rate on the performance of rubber modified asphalt, and provided a reference for its preparation.

  16. 40 CFR 52.2054 - Control of asphalt paving material.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Control of asphalt paving material. 52... asphalt paving material. (a) Notwithstanding any provisions to the contrary in the Pennsylvania Implementation Plan, the Pennsylvania Department of Transportation shall restrict the annual usage of asphalts...

  17. 40 CFR 52.2054 - Control of asphalt paving material.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Control of asphalt paving material. 52... asphalt paving material. (a) Notwithstanding any provisions to the contrary in the Pennsylvania Implementation Plan, the Pennsylvania Department of Transportation shall restrict the annual usage of asphalts...

  18. 40 CFR 52.2054 - Control of asphalt paving material.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Control of asphalt paving material. 52... asphalt paving material. (a) Notwithstanding any provisions to the contrary in the Pennsylvania Implementation Plan, the Pennsylvania Department of Transportation shall restrict the annual usage of asphalts...

  19. Full-Depth Asphalt Pavements for Parking Lots and Driveways.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    The latest information for designing full-depth asphalt pavements for parking lots and driveways is covered in relationship to the continued increase in vehicle registration. It is based on The Asphalt Institute's Thickness Design Manual, Series No. 1 (MS-1), Seventh Edition, which covers all aspects of asphalt pavement thickness design in detail,…

  20. Asphalt and risk of cancer in man.

    PubMed Central

    Chiazze, L; Watkins, D K; Amsel, J

    1991-01-01

    Epidemiological publications regarding the carcinogenic potential of asphalt (bitumen) are reviewed. In 1984 the International Agency for Research on Cancer (IARC) stated that there is "inadequate evidence that bitumens alone are carcinogenic to humans." They did, however, conclude that animal data provided sufficient evidence for the carcinogenicity of certain extracts of steam refined and air refined bitumens. In the absence of data on man, IARC considered it reasonable to regard chemicals with sufficient evidence of carcinogenicity in animals as if they presented a carcinogenic risk to man. Epidemiological data for man accumulated since the IARC report do not fulfil the criteria for showing a causal association between exposure to asphalt and development of cancer. The studies cited all suffer from a lack of data on exposure or potential confounders, which are necessary to establish whether or not such an association may or may not exist. In view of the evidence (or lack thereof) regarding asphalt today, an appropriate public health attitude suggests at least that action be taken to protect those working with asphalt by monitoring the workplace, taking whatever steps are possible to minimise exposures and to inform workers of potential hazards. At the same time, a need exists for well designed analytical epidemiological studies to determine whether a risk of cancer in man exists from exposure to asphalt. PMID:1878310

  1. Sulfur-extended asphalt pavement: a three-year progress report. Final report

    SciTech Connect

    Van Bramer, T.F.

    1986-10-01

    This report documents post-construction performance of a sulfur-extended asphalt (SEA) pavement and a conventional pavement used as a control, monitored over a 3-year period. The SEA pavement used 30% sulfur by total weight of the binder. Both pavements were placed under New York State specifications during the summer of 1980 on Rtes 118 and 202 in Westchester County, New York. After 3 years, overall condition of both the SEA and control pavements was satisfactory. The two did not differ significantly in deflection, rutting, friction, or aggregate degradation. Data obtained from analysis of pavement cores showed that the stability of the SEA mix was equal to or higher than that of the control at all ages. Similarly, its resilient modulus was greater at all ages and temperatures. Although tensile-strength ratios measured for both mixes indicated a potential for stripping, virtually none was observed in any of the field cores for either pavement at any age.

  2. Gas permeability measurements on asphalts using the electrodynamic balance

    SciTech Connect

    Periasamy, R.; Newsome, J.R.; Andrady, A.L.; Ensor, D.S. )

    1990-07-01

    Volatilization, oxide degradation, and steric hardening are the degradation processes believed to be responsible for the weathering of asphalts. The fundamental mechanisms that govern the rates at which these degradation processes occur are not understood, but the transport of oxygen through the asphalt matrix is an important aspect of the weathering of asphalts under field conditions. Therefore, the measurement of diffusion, solubility, and permeability constants for oxygen in asphalts is crucial to better understand the long-term weathering of the asphalt materials. A novel and precise gravimetric technique, hitherto not applied in asphalt research is described here: an electrodynamic balance is used in this technique for the measurement of key transport properties for oxygen in micrometer-size asphalt particle samples.

  3. Con: Phosphate binders in chronic kidney disease.

    PubMed

    Kestenbaum, Bryan

    2016-02-01

    Phosphate binders are prescribed to chronic kidney disease (CKD) patients based on associations of serum phosphate concentrations with mortality and calcification, experimental evidence for direct calcifying effects of phosphate on vascular smooth muscle tissue and the central importance of phosphate retention in CKD-mineral and bone disorder (CKD-MBD). Current knowledge regarding phosphate metabolism in CKD provides important insight into disease mechanisms and supports future clinical trials of phosphate binders in CKD patients to determine the impact of these medications on clinically relevant outcomes. The risks and benefits of phosphate binders cannot be inferred from association studies of serum phosphate concentrations, which are inconsistent and subject to confounding, animal-experimental data, which are based on conditions that differ from human disease, or physiological arguments, which are limited to known regulatory factors. Many interventions that targeted biochemical pathways suggested by association studies and suspected biological importance have yielded null or harmful results. Clinical trials of phosphate binders are of high clinical and scientific importance to nephrology. Demonstration of reduced rates of clinical disease in such trials could lead to important health benefits for CKD patients, whereas negative results would refocus efforts to understand and treat CKD-MBD. Clinical trials that employ highly practical or 'pragmatic' designs represent an optimal approach for determining the safety and effectiveness of phosphate binders in real-world settings. Absent clinical trial data, observational studies of phosphate binders in large CKD populations could provide important information regarding the benefits, risks and/or unintended side effects of these medications. PMID:26681747

  4. Sulfur extended asphalt pavement evaluation: Executive summary

    NASA Astrophysics Data System (ADS)

    Mahoney, J. P.

    1982-09-01

    This summary report overviews two previously issued study reports. One report assesses The availability and pricing of sulfur with respect to sulfur extended asphalt (SEA) paving mixture is assessed. A laboratory oriented testing program which was principally used to examine the durability and aging characteristics of SEA paving mixtures is reported.

  5. Microbial Life in a Liquid Asphalt Desert

    NASA Astrophysics Data System (ADS)

    Schulze-Makuch, Dirk; Haque, Shirin; de Sousa Antonio, Marina Resendes; Ali, Denzil; Hosein, Riad; Song, Young C.; Yang, Jinshu; Zaikova, Elena; Beckles, Denise M.; Guinan, Edward; Lehto, Harry J.; Hallam, Steven J.

    2011-04-01

    Pitch Lake in Trinidad and Tobago is a natural asphalt reservoir nourished by pitch seepage, a form of petroleum that consists of mostly asphaltines, from the surrounding oil-rich region. During upward seepage, pitch mixes with mud and gases under high pressure, and the lighter portion evaporates or is volatilized, which produces a liquid asphalt residue characterized by low water activity, recalcitrant carbon substrates, and noxious chemical compounds. An active microbial community of archaea and bacteria, many of them novel strains (particularly from the new Tar ARC groups), totaling a biomass of up to 107 cells per gram, was found to inhabit the liquid hydrocarbon matrix of Pitch Lake. Geochemical and molecular taxonomic approaches revealed diverse, novel, and deeply branching microbial lineages with the potential to mediate anaerobic hydrocarbon degradation processes in different parts of the asphalt column. In addition, we found markers for archaeal methane metabolism and specific gene sequences affiliated with facultative and obligate anaerobic sulfur- and nitrite-oxidizing bacteria. The microbial diversity at Pitch Lake was found to be unique when compared to microbial communities analyzed at other hydrocarbon-rich environments, which included Rancho Le Brea, a natural asphalt environment in California, USA, and an oil well and a mud volcano in Trinidad and Tobago, among other sites. These results open a window into the microbial ecology and biogeochemistry of recalcitrant hydrocarbon matrices and establish the site as a terrestrial analogue for modeling the biotic potential of hydrocarbon lakes such as those found on Saturn's largest moon Titan.

  6. Freeforming objects with low-binder slurry

    DOEpatents

    Cesarano, III, Joseph; Calvert, Paul D.

    2000-01-01

    In a rapid prototyping system, a part is formed by depositing a bead of slurry that has a sufficient high concentration of particles to be pseudoplastic and almost no organic binders. After deposition the bead is heated to drive off sufficient liquid to cause the bead to become dilatant.

  7. Organic Binder Developments for Solid Freeform Fabrication

    NASA Technical Reports Server (NTRS)

    Cooper, Ken; Mobasher, Amir A.

    2003-01-01

    A number of rapid prototyping techniques are under development at Marshall Space Flight Center's (MSFC) National Center for Advanced Manufacturing Rapid Prototyping Laboratory. Commercial binder developments in creating solid models for rapid prototyping include: 1) Fused Deposition Modeling; 2) Three Dimensional Printing; 3) Selective Laser Sintering (SLS). This document describes these techniques developed by the private sector, as well as SLS undertaken by MSFC.

  8. Mesoscale modelling of PBX. Binder effects.

    NASA Astrophysics Data System (ADS)

    Milne, Alec; Dunnett, Jim; Bourne, Neil

    2007-06-01

    In earlier work we have studied aspects of shock to detonation transition and detonation structure in polymer bonded explosives on the scale of the largest grains (the mesoscale) to augment continuum models for these processes. Building blocks have been unreacted Hugoniots of mixtures, mapping from experiment (2D micrographs and 3D tomography) for accurate initial conditions and details of cavity collapse mechanisms as hot spots for ignition. Recently we have applied continuum mixture theory (multi-phase modelling) to dirty binder (the mixture of explosive crystal fines and binder that surrounds the large grains) and validated it for the unreacted Hugoniot of a range of UK explosives. In this paper we build on all of this work and report our progress in using continuum mixture theory to model the reactive behaviour of dirty binder. We begin by considering the binder on its own and then use this continuum mixture mode in conjunction with mesoscale representations of PBX. We consider PBX9501 and a UK PBX as examples. We identify the numerical modelling issues that have arisen, our current approaches and our plans for further development and testing.

  9. 21 CFR 880.5160 - Therapeutic medical binder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Therapeutic medical binder. 880.5160 Section 880...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5160 Therapeutic medical binder. (a) Identification. A therapeutic medical binder is...

  10. 21 CFR 880.5160 - Therapeutic medical binder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Therapeutic medical binder. 880.5160 Section 880...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5160 Therapeutic medical binder. (a) Identification. A therapeutic medical binder is...

  11. 21 CFR 880.5160 - Therapeutic medical binder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Therapeutic medical binder. 880.5160 Section 880...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5160 Therapeutic medical binder. (a) Identification. A therapeutic medical binder is...

  12. Iron-based phosphate binders: do they offer advantages over currently available phosphate binders?

    PubMed Central

    Negri, Armando Luis; Ureña Torres, Pablo Antonio

    2015-01-01

    Increased cardiovascular morbidity and mortality has been associated with the hyperphosphatemia seen in patients with end-stage chronic kidney disease (CKD). Oral phosphate binders are prescribed in these patients to prevent intestinal absorption of dietary phosphate and reduce serum phosphate. In prospective observational cohorts they have shown to decrease all-cause and cardiovascular mortality risk. Different problems have been associated with currently available phosphate binders as positive calcium balance and impaired outcomes with calcium-based phosphate binders or increased costs with non-calcium-based phosphate binders. Iron-based phosphate binders represent a new class of phosphate binders. Several iron-based phosphate binders have undergone testing in clinical trials. Ferric citrate (JTT-751) and sucroferric oxyhydroxide (PA21) are the two iron-based binders that have passed to the clinical field after being found safe and effective in decreasing serum phosphate. Iron from ferric citrate is partially absorbed compared to sucroferric oxyhydroxide. Ferric citrate usage could result in an important reduction in erythropoiesis-stimulating agent (ESA) and IV iron usage, resulting in significant cost savings. Sucroferric oxyhydroxide was effective in lowering serum phosphorus in dialysis patients with similar efficacy to sevelamer carbonate, but with lower pill burden, and better adherence. Ferric citrate may be more suited for the treatment of chronic hyperphosphatemia in CKD patients requiring iron supplements but its use may have been hampered by potential aluminum overload, as citrate facilitates its absorption; sucroferric oxyhydroxide may be more suited for hyperphosphatemic CKD patients not requiring iron supplementation, with low pill burden. PMID:25815172

  13. Linear viscoelastic limits of asphalt concrete at low and intermediate temperatures

    NASA Astrophysics Data System (ADS)

    Mehta, Yusuf A.

    The purpose of this dissertation is to demonstrate the hypothesis that a region at which the behavior of asphalt concrete can be represented as a linear viscoelastic material can be determined at low and intermediate temperatures considering the stresses and strains typically developed in the pavements under traffic loading. Six mixtures containing different aggregate gradations and nominal maximum aggregate sizes varying from 12.5 to 37.5 mm were used in this study. The asphalt binder grade was the same for all mixtures. The mixtures were compacted to 7 +/- 1% air voids, using the Superpave Gyratory Compactor. Tests were conducted at low temperatures (-20°C and -10°C), using the indirect tensile test machine, and at intermediate temperatures (4°C and 20°C), using the Superpave shear machine. To determine the linear viscoelastic range of asphalt concrete, a relaxation test for 150 s, followed by a creep test for another 150 s, was conducted at 150 and 200 microstrains (1 microstrain = 1 x 10-6), at -20°C, and at 150 and 300 microstrains, at -10°C. A creep test for 200 s, followed by a recovery test for another 200 s, was conducted at stress levels up to 800 kPa at 4°C and up to 500 kPa at 20°C. At -20°C and -10°C, the behavior of the mixtures was linear viscoelastic at 200 and 300 microstrains, respectively. At intermediate temperatures (4°C and 20°C), an envelope defining the linear and nonlinear region in terms of stress as a function of shear creep compliance was constructed for all the mixtures. For creep tests conducted at 20°C, it was discovered that the commonly used protocol to verify the proportionality condition of linear viscoelastic behavior was unable to detect the appearance of nonlinear behavior at certain imposed shear stress levels. Said nonlinear behavior was easily detected, however, when checking the satisfaction of the superposition condition. The envelope constructed for determining when the material becomes nonlinear should be

  14. Quantitative evaluation of rejuvenators to restore embrittlement temperatures in oxidized asphalt mixtures using acoustic emission

    NASA Astrophysics Data System (ADS)

    Sun, Zhe; Farace, Nicholas; Arnold, Jacob; Behnia, Behzad; Buttlar, William G.; Reis, Henrique

    2015-03-01

    Towards developing a method capable to assess the efficiency of rejuvenators to restore embrittlement temperatures of oxidized asphalt binders towards their original, i.e., unaged values, three gyratory compacted specimens were manufactured with mixtures oven-aged for 36 hours at 135 °C. In addition, one gyratory compacted specimen manufactured using a short-term oven-aged mixture for two hours at 155 °C was used for control to simulate aging during plant production. Each of these four gyratory compacted specimens was then cut into two cylindrical specimen 5 cm thick for a total of six 36-hour oven-aged specimens and two short term aging specimens. Two specimens aged for 36 hours and the two short-term specimens were then tested using an acoustic emission approach to obtain base acoustic emission response of short-term and severely-aged specimens. The remaining four specimens oven-aged for 36 hours were then treated by spreading their top surface with rejuvenator in the amount of 10% of the binder by weight. These four specimens were then tested using the same acoustic emission approach after two, four, six, and eight weeks of dwell time. It was observed that the embrittlement temperatures of the short-term aged and severely oven-aged specimens were -25 °C and - 15 °C, respectively. It was also observed that after four weeks of dwell time, the rejuvenator-treated samples had recuperated the original embrittlement temperatures. In addition, it was also observed that the rejuvenator kept acting upon the binder after four weeks of dwell time; at eight weeks of dwell time, the specimens had an embrittlement temperature about one grade cooler than the embrittlement temperature corresponding to the short-term aged specimen.

  15. Analysis of asphalt-based roof systems using thermal analysis

    SciTech Connect

    Paroli, R.M.; Delgado, A.H.

    1996-10-01

    Asphalt is used extensively in roofing applications. Traditionally, it is used in a built-up roof system, where four or five plies are applied in conjunction with asphalt. This is labour intensive and requires good quality assurance on the roof top. Alternatively, asphalt can be used in a polymer-modified sheet where styrene-butadiene-styrene (SBS) or atactic polypropylene (APP) are added to the asphalt shipped in a roll where reinforcement (e.g., glass fibre mat) has been added. Regardless of the system used, the roof must be able to withstand the environmental loads such UV, heat, etc. Thermoanalytical techniques such as DSC, DMA, TMA and TG/DTA are ideally suited to monitor the weathering of asphalt. This paper presents data obtained using these techniques and shows how the performance of asphalt-based roof systems can be followed by thermal analysis.

  16. Research on Surfactant Warm Mix Asphalt Construction Technology

    NASA Astrophysics Data System (ADS)

    Li, Guoliang; Sun, Jingxin; Guo, Xiufeng

    Discharging temperature of hot asphalt mixture is about 150°C-185°C, volatilization of asphalt fume harms people's health and fuel cost is high. Jinan Urban Construction Group applies PTL/01 asphalt warm mix agent to produce warm mix asphalt to construction of urban roads' asphalt bituminous pavement. After comparing it with performance of traditional hot asphalt mixture, mixing temperature may be reduced by 30°C-60°C, emission of poisonous gas is reduced, energy conservation and environmental protection are satisfied, construction quality reaches requirements of construction specifications and economic, social and environmental benefits are significant. Thus, it can be used for reference for green construction of urban roads.

  17. Seal coats and asphalt recycling. Transportation research record

    SciTech Connect

    1995-12-31

    The papers in this volume deal with various facets of seal coats and asphalt recycling; they should be of interest to state and local construction, design, materials, maintenance, and research engineers as well as contractors and material producers. Authors describe their work related to the design, construction, and performance of seal coats. The relationship between asphalt mixture characteristics and design and the frictional resistance of bituminous wearing course mixtures is reported, and research efforts related to asphalt recycling are explained.

  18. Production variability analysis of hot-mixed asphalt concrete containing reclaimed asphalt pavement. Final research report

    SciTech Connect

    Solaimanian, M.; Kennedy, T.W.

    1995-02-01

    A research project was undertaken to evaluate the production and construction variability of Hot Mix Asphalt Concrete (HMAC) containing high quantities of reclaimed asphalt pavement (RAP) material. Four construction projects were selected for this purpose. Two of the projects used 35 percent RAP material (both type-C mixes), while the other two used 40 percent (a type-B mix) and 50 percent (a type-D mix) of the RAP material, respectively. The projects differed in sizes, with total construction tonnage ranging from 10.9 million kg to 27.2 million kg (12,000 to 30,000 tons). In all cases, dedicated stockpiles of RAP material were used. Analysis was performed on the results obtained from the tests. The gradation and asphalt content deviations, air voids, penetration and viscosities, and stabilities, were included in the analysis. Pay adjustment factors were determined for gradation and asphalt content deviation, as well as for air voids (based on TxDOT Specification 3007). In general, these high-percent RAP projects indicated a variability higher than that of a typical HMAC without RAP. The pay adjustment factors for gradation and asphalt content deviation were lower than typical values. The construction gradations were finer than the job-mix formula target gradations, possibly a result of aggregate crushing during the milling operation.

  19. Alkali-metal silicate binders and methods of manufacture

    NASA Technical Reports Server (NTRS)

    Schutt, J. B. (Inventor)

    1979-01-01

    A paint binder is described which uses a potassium or sodium silicate dispersion having a silicon dioxide to alkali-metal oxide mol ratio of from 4.8:1 to 6.0:1. The binder exhibits stability during both manufacture and storage. The process of making the binder is predictable and repeatable and the binder may be made with inexpensive components. The high mol ratio is achieved with the inclusion of a silicon dioxide hydrogel. The binder, which also employs a silicone, is in the final form of a hydrogel sol.

  20. Field testing of asphalt-emulsion radon-barrier system

    SciTech Connect

    Hartley, J.N.; Freeman, H.D.; Baker, E.G.; Elmore, M.R.; Nelson, D.A.; Voss, C.F.; Koehmstedt, P.L.

    1981-09-01

    Three years of laboratory and field testing have demonstrated that asphalt emulsion seals are effective radon diffusion barriers. Both laboratory and field tests in 1979, 1980 and 1981 have shown that an asphalt emulsion seal can reduce radon fluxes by greater than 99.9%. The effective diffusion coefficient for the various asphalt emulsion admix seals averages about 10/sup -6/ cm/sup 2//s. The 1981 joint field test is a culmination of all the technology developed to date for asphalt emulsion radon barrier systems. Preliminary results of this field test and the results of the 1980 field test are presented. 18 figures, 6 tables.

  1. Hanford Permanent Isolation Barrier Program: Asphalt technology development

    SciTech Connect

    Freeman, H.D.; Romine, R.A.

    1994-11-01

    An important component of the Hanford Permanent Isolation Barrier is the use of a two-layer composite asphalt system, which provides backup water diversion capabilities if the primary capillary barrier fails to meet infiltration goals. Because of asphalt`s potential to perform to specification over the 1000-year design life criterion, a composite asphalt barrier (HMAC/fluid-applied polymer-modified asphalt) is being considered as an alternative to the bentonite clay/high density poly(ethylene) barriers for the low-permeability component of the Hanford Permanent Isolation Barrier. The feasibility of using asphalt as a long-term barrier is currently being studied. Information that must be known is the ability of asphalt to retain desirable physical properties over a period of 1000 years. This paper presents the approach for performing accelerated aging tests and evaluating the performance of samples under accelerated conditions. The results of these tests will be compared with asphalt artifact analogs and the results of modeling the degradation of the selected asphalt composite to make life-cycle predictions.

  2. Asphalt compatibility testing using the automated Heithaus titration test

    SciTech Connect

    Pauli, A.T.

    1996-12-31

    The Heithaus titration test or variations of the test have been used for over 35 years to predict compatibilities of blends of asphalts from different crude sources. Asphalt compatibility is determined from three calculated parameters that measure the state of peptization of an asphalt or asphalt blend. The parameter p{sub a} is a measure of the peptizability of the asphaltenes. The parameter p{sub a} is a measure of the peptizing power of the maltenes, and the parameter P, derived from p{sub a} and p{sub o} values, is a measure of the overall state of peptization of the asphalt or asphalt blend. In Heithaus original procedure, samples of asphalt were dissolved in toluene and titrated with n-heptane in order to initiate flocculation. The onset of flocculation was detected either by photography or by spotting a filter paper with a small amount of the titrated solution. Recently, an {open_quotes}automated{close_quotes} procedure, after Hotier and Robin, has been developed for use with asphalt. In the automated method UV-visible spectrophotometric detection measures the onset of flocculation as a peak with the percent transmittance plotted as a function of the volume of titrating solvent added to a solution of asphalt. The automated procedure has proven to be less operator dependent and much faster than the original Heithaus procedure. Results from the automated procedure show the data to be consistent with results from the original, {open_quotes}classical{close_quotes} Heithaus procedure.

  3. Phenomena during thermal removal of binders

    NASA Astrophysics Data System (ADS)

    Hrdina, Kenneth Edward

    The research presented herein has focused on debinding of an ethylene copolymer from a SiC based molded ceramic green body. Examination of the binder burnout process was carried out by breaking down the process into two distinct regions: those events which occur before any weight loss begins, and those events occurring during binder removal. Below the temperature of observed binder loss (175sp°C), both reversible and irreversible displacement was observed to occur. The displacement was accounted for by relaxation of molding stresses, thermal expansion of the system, and melting of the semicrystalline copolymer occurring during heating. Upon further heating the binder undergoes a two stage thermal degradation process. In the first stage, acetic acid is the only degradation product formed, as determined by GC/MS analysis. In this stage, component shrinkage persisted and it was found that one unit volume of shrinkage corresponded with one unit volume of binder removed, indicating that no porosity developed. The escaping acetic acid effluents must diffuse through liquid polymer filled porous regions to escape. The gas pressure of the acetic acid species produced in the first stage of the thermal degradation may exceed the ambient pressure promoting bubble formation. Controlling the heating rate of the specimen maintains the gas pressure below the bubbling threshold and minimizes the degradation time. Experiments have determined the kinetics of the reaction in the presence of the high surface area (10-15msp2/g) ceramic powder and then verified that acetic acid was diffusing through the polymer phase to the specimen surface where evaporation is taking place. The sorption method measured the diffusivity and activity of acetic acid within the filled ceramic system within a TGA. These data were incorporated into a Fickian type model which included the rate of generation of the diffusing species. The modeling process involved prediction of the bloating temperature as a

  4. The Adequacy of Phosphorus Binder Prescriptions Among American Hemodialysis Patients

    PubMed Central

    Huml, Anne M.; Sullivan, Catherine M.; Leon, Janeen B.; Sehgal, Ashwini R.

    2013-01-01

    Because hemodialysis treatment has a limited ability to remove phosphorus, dialysis patients must restrict dietary phosphorus intake and use phosphorus binding medication. Among patients with restricted dietary phosphorus intake (1000 mg/d), phosphorus binders must bind about 250 mg of excess phosphorus per day and among patients with more typical phosphorus intake (1500 mg/d), binders must bind about 750 mg per day. To determine the phosphorus binding capacity of binder prescriptions among American hemodialysis patients, we undertook a cross-sectional study of a random sample of in-center chronic hemodialysis patients. We obtained data for one randomly selected patient from 244 facilities nationwide. About one-third of patients had hyperphosphatemia (serum phosphorus level > 5.5 mg/dL). Among the 224 patients prescribed binders, the mean phosphorus binding capacity was 256 mg/d (SD 143). 59% of prescriptions had insufficient binding capacity for restricted dietary phosphorus intake, and 100% had insufficient binding capacity for typical dietary phosphorus intake. Patients using two binders had a higher binding capacity than patients using one binder (451 vs. 236 mg/d, p <0.001). A majority of binder prescriptions have insufficient binding capacity to maintain phosphorus balance. Use of two binders results in higher binder capacity. Further work is needed to understand the impact of binder prescriptions on mineral balance and metabolism and to determine the value of substantially increasing binder prescriptions. PMID:23013171

  5. Effects of reclaimed asphalt pavement on indirect tensile strength test of foamed asphalt mix tested in dry condition

    NASA Astrophysics Data System (ADS)

    Yati Katman, Herda; Rasdan Ibrahim, Mohd; Yazip Matori, Mohd; Norhisham, Shuhairy; Ismail, Norlela

    2013-06-01

    Indirect tensile strength (ITS) test was conducted to analyse strength of the foamed asphalt mixes incorporating reclaimed asphalt pavement. Samples were tested for ITS after cured in the oven at 40°C for 72 hours. This testing condition known as dry condition or unconditioned. Laboratory results show that reclaimed asphalt pavement (RAP) contents insignificantly affect the ITS results. ITS results significantly affected by foamed bitumen contents.

  6. Microbial life in a liquid asphalt desert.

    PubMed

    Schulze-Makuch, Dirk; Haque, Shirin; de Sousa Antonio, Marina Resendes; Ali, Denzil; Hosein, Riad; Song, Young C; Yang, Jinshu; Zaikova, Elena; Beckles, Denise M; Guinan, Edward; Lehto, Harry J; Hallam, Steven J

    2011-04-01

    Pitch Lake in Trinidad and Tobago is a natural asphalt reservoir nourished by pitch seepage, a form of petroleum that consists of mostly asphaltines, from the surrounding oil-rich region. During upward seepage, pitch mixes with mud and gases under high pressure, and the lighter portion evaporates or is volatilized, which produces a liquid asphalt residue characterized by low water activity, recalcitrant carbon substrates, and noxious chemical compounds. An active microbial community of archaea and bacteria, many of them novel strains (particularly from the new Tar ARC groups), totaling a biomass of up to 10(7) cells per gram, was found to inhabit the liquid hydrocarbon matrix of Pitch Lake. Geochemical and molecular taxonomic approaches revealed diverse, novel, and deeply branching microbial lineages with the potential to mediate anaerobic hydrocarbon degradation processes in different parts of the asphalt column. In addition, we found markers for archaeal methane metabolism and specific gene sequences affiliated with facultative and obligate anaerobic sulfur- and nitrite-oxidizing bacteria. The microbial diversity at Pitch Lake was found to be unique when compared to microbial communities analyzed at other hydrocarbon-rich environments, which included Rancho Le Brea, a natural asphalt environment in California, USA, and an oil well and a mud volcano in Trinidad and Tobago, among other sites. These results open a window into the microbial ecology and biogeochemistry of recalcitrant hydrocarbon matrices and establish the site as a terrestrial analogue for modeling the biotic potential of hydrocarbon lakes such as those found on Saturn's largest moon Titan. PMID:21480792

  7. Composite binders for concrete with reduced permeability

    NASA Astrophysics Data System (ADS)

    Fediuk, R.; Yushin, A.

    2016-02-01

    Composite binder consisting of cement (55%), acid fly ash (40%) and limestone (5%) has been designed. It is obtained by co-milling to a specific surface of 550 kg/m2, it has an activity of 77.3 MPa and can produce a more dense cement stone structure. Integrated study revealed that the concrete on the composite binder basis provides an effective diffusion coefficient D. So we can conclude that the concrete layer protects buildings from toxic effects of expanded polystyrene. Low water absorption of the material (2.5% by weight) is due to the structure of its cement stone pore space. Besides lime powder prevents the penetration of moisture, reduces water saturation of the coverage that has a positive effect on useful life period. It also explains rather low water vapor permeability of the material - 0.021 mg/(m- hour-Pa).

  8. Binder segregation in the processing of ceramics

    SciTech Connect

    Zhang, Yao; Uematsu, Keizo

    1996-12-31

    The surface segregation of poly(vinyl alcohol) during the drying process was quantitatively studied by a model experiment of one-dimensional drying and a mathematical simulation. The drying behavior of the slurry with binder and the relationship between the binder segregation and defect formation in compact also were examined. The binder segregation shortens the constant rate period, and drying shrinkage continues occurring during the early fall rate period. The PVA segregation increased with increasing drying temperature and PVA initial concentration. The segregation was significantly restrained by full adsorption of PVA on the alumina particle surface before drying at a low concentration. The segregation in spray dried granules was also directly observed by the immersion liquid technique. The hard shell of the granule is responsible for a low packing density region between the granules. The mathematical simulation agreed with the experimental results very well. This simulation has great potential to predict the segregation of soluble components in thick films and small granules where it is difficult to determine the component distribution directly.

  9. Good news from the bottom: US asphalt market 1993

    SciTech Connect

    Not Available

    1993-09-22

    For US refiners faced with numerous tough challenges in 1993, the US asphalt market recovery may have provided some welcome news for those watching the bottom line. Higher prices and increased sales made the asphalt market a summertime profit center for many US refiners and marketers -- for the first time in years.

  10. Effects of conductive fillers on temperature distribution of asphalt pavements

    NASA Astrophysics Data System (ADS)

    Mingyu, Chen; Shaopeng, Wu; Yuan, Zhang; Hong, Wang

    2010-05-01

    The sun provides a cheap and abundant source of clean and renewable energy. Solar cells have been used to capture this energy and generate electricity. A more useful form of the solar cell would be asphalt pavements, which get heated up by solar radiation. Graphite powders are utilized as thermal conductive fillers to make an asphalt collector conductive so as to improve the efficiency of the asphalt collector. Accounting for the important application conditions and evaluating the effects of the heat conductive materials and the solar energy absorbability of the conductive asphalt collector, a finite element model has been developed to predict temperature distributions in the conductive asphalt solar collector. In this study, an experimental validation exercise was conducted using the measured data taken from full-depth asphalt slabs. Validation results showed that the model can satisfactorily predict the temperature distributions in asphalt concrete slabs. The optimal depth is 25-50 mm for placing pipes that serve as the heat exchanger. Meanwhile, the effect of the surroundings on the solar energy potential of the asphalt collector was noticeable.

  11. 7 CFR 2902.36 - Concrete and asphalt release fluids.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Concrete and asphalt release fluids. 2902.36 Section... PROCUREMENT Designated Items § 2902.36 Concrete and asphalt release fluids. (a) Definition. Products that are designed to provide a lubricating barrier between the composite surface materials (e.g., concrete...

  12. 7 CFR 3201.36 - Concrete and asphalt release fluids.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Concrete and asphalt release fluids. 3201.36 Section... PROCUREMENT Designated Items § 3201.36 Concrete and asphalt release fluids. (a) Definition. Products that are designed to provide a lubricating barrier between the composite surface materials (e.g., concrete...

  13. 7 CFR 3201.65 - Concrete and asphalt cleaners.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Concrete and asphalt cleaners. 3201.65 Section 3201... PROCUREMENT Designated Items § 3201.65 Concrete and asphalt cleaners. (a) Definition. Chemicals used in concrete etching as well as to remove petroleum-based soils, lubricants, paints, mastics, organic...

  14. 7 CFR 3201.65 - Concrete and asphalt cleaners.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Concrete and asphalt cleaners. 3201.65 Section 3201... PROCUREMENT Designated Items § 3201.65 Concrete and asphalt cleaners. (a) Definition. Chemicals used in concrete etching as well as to remove petroleum-based soils, lubricants, paints, mastics, organic...

  15. 7 CFR 3201.36 - Concrete and asphalt release fluids.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Concrete and asphalt release fluids. 3201.36 Section... PROCUREMENT Designated Items § 3201.36 Concrete and asphalt release fluids. (a) Definition. Products that are designed to provide a lubricating barrier between the composite surface materials (e.g., concrete...

  16. 7 CFR 3201.65 - Concrete and asphalt cleaners.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Concrete and asphalt cleaners. 3201.65 Section 3201... PROCUREMENT Designated Items § 3201.65 Concrete and asphalt cleaners. (a) Definition. Chemicals used in concrete etching as well as to remove petroleum-based soils, lubricants, paints, mastics, organic...

  17. 7 CFR 2902.36 - Concrete and asphalt release fluids.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Concrete and asphalt release fluids. 2902.36 Section... PROCUREMENT Designated Items § 2902.36 Concrete and asphalt release fluids. (a) Definition. Products that are designed to provide a lubricating barrier between the composite surface materials (e.g., concrete...

  18. 7 CFR 3201.36 - Concrete and asphalt release fluids.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Concrete and asphalt release fluids. 3201.36 Section... PROCUREMENT Designated Items § 3201.36 Concrete and asphalt release fluids. (a) Definition. Products that are designed to provide a lubricating barrier between the composite surface materials (e.g., concrete...

  19. 40 CFR 443.40 - Applicability; description of the linoleum and printed asphalt felt subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... linoleum and printed asphalt felt subcategory. 443.40 Section 443.40 Protection of Environment... THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.40 Applicability; description of the linoleum and printed asphalt...

  20. 40 CFR Table 1 of Subpart Aaaaaaa... - Emission Limits for Asphalt Processing (Refining) Operations

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 15 2012-07-01 2012-07-01 false Emission Limits for Asphalt Processing... Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and Information... of Part 63—Emission Limits for Asphalt Processing (Refining) Operations For * * * You must meet...

  1. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable...

  2. 40 CFR Table 1 of Subpart Aaaaaaa... - Emission Limits for Asphalt Processing (Refining) Operations

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false Emission Limits for Asphalt Processing... Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and Information... of Part 63—Emission Limits for Asphalt Processing (Refining) Operations For * * * You must meet...

  3. 40 CFR Table 1 of Subpart Aaaaaaa... - Emission Limits for Asphalt Processing (Refining) Operations

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 15 2013-07-01 2013-07-01 false Emission Limits for Asphalt Processing... Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and Information... of Part 63—Emission Limits for Asphalt Processing (Refining) Operations For * * * You must meet...

  4. 40 CFR 443.40 - Applicability; description of the linoleum and printed asphalt felt subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... linoleum and printed asphalt felt subcategory. 443.40 Section 443.40 Protection of Environment... PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.40 Applicability; description of the linoleum and printed asphalt felt subcategory....

  5. 40 CFR Table 1 of Subpart Aaaaaaa... - Emission Limits for Asphalt Processing (Refining) Operations

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Emission Limits for Asphalt Processing... Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and Information... of Part 63—Emission Limits for Asphalt Processing (Refining) Operations For * * * You must meet...

  6. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable...

  7. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to...

  8. 40 CFR 443.40 - Applicability; description of the linoleum and printed asphalt felt subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... linoleum and printed asphalt felt subcategory. 443.40 Section 443.40 Protection of Environment... THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.40 Applicability; description of the linoleum and printed asphalt...

  9. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable...

  10. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable...

  11. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 15 2014-07-01 2014-07-01 false Emission Limits for Asphalt Roofing... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * *...

  12. 40 CFR 443.40 - Applicability; description of the linoleum and printed asphalt felt subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... linoleum and printed asphalt felt subcategory. 443.40 Section 443.40 Protection of Environment... THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.40 Applicability; description of the linoleum and printed asphalt...

  13. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Emission Limits for Asphalt Roofing... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * *...

  14. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable...

  15. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to...

  16. 40 CFR Table 1 of Subpart Aaaaaaa... - Emission Limits for Asphalt Processing (Refining) Operations

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 15 2014-07-01 2014-07-01 false Emission Limits for Asphalt Processing... Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and Information... of Part 63—Emission Limits for Asphalt Processing (Refining) Operations For * * * You must meet...

  17. 40 CFR 443.40 - Applicability; description of the linoleum and printed asphalt felt subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... linoleum and printed asphalt felt subcategory. 443.40 Section 443.40 Protection of Environment... PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.40 Applicability; description of the linoleum and printed asphalt felt subcategory....

  18. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable...

  19. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable to...

  20. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable to...

  1. 40 CFR 443.20 - Applicability; description of the asphalt concrete subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asphalt concrete subcategory. 443.20 Section 443.20 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Concrete Subcategory § 443.20 Applicability; description of the asphalt concrete subcategory. The provisions of this subpart are applicable...

  2. 40 CFR 443.20 - Applicability; description of the asphalt concrete subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asphalt concrete subcategory. 443.20 Section 443.20 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Concrete Subcategory § 443.20 Applicability; description of the asphalt concrete subcategory. The provisions of this subpart are applicable to...

  3. 40 CFR 443.20 - Applicability; description of the asphalt concrete subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asphalt concrete subcategory. 443.20 Section 443.20 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Concrete Subcategory § 443.20 Applicability; description of the asphalt concrete subcategory. The provisions of this subpart are applicable...

  4. 40 CFR 443.20 - Applicability; description of the asphalt concrete subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asphalt concrete subcategory. 443.20 Section 443.20 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Concrete Subcategory § 443.20 Applicability; description of the asphalt concrete subcategory. The provisions of this subpart are applicable...

  5. 40 CFR 443.20 - Applicability; description of the asphalt concrete subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asphalt concrete subcategory. 443.20 Section 443.20 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Concrete Subcategory § 443.20 Applicability; description of the asphalt concrete subcategory. The provisions of this subpart are applicable to...

  6. Monitoring asphalt pavement damages using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Mettas, Christodoulos; Themistocleous, Kyriacos; Neocleous, Kyriacos; Christofe, Andreas; Pilakoutas, Kypros; Hadjimitsis, Diofantos

    2015-06-01

    One of the main issues in the maintenance plans of road agencies or governmental organizations is the early detection of damaged asphalt pavements. The development of a smart and non-destructive systematic technique for monitoring damaged asphalt pavements is considered a main priority to fill this gap. During the 1970's, remote sensing was used to map road surface distress, while during the last decade, remote sensing became more advanced, thereby assisting in the evolution of the identification and mapping of roads. Various techniques were used in order to explore condition, age, weaknesses and imperfections of asphalted pavements. These methods were fairly successful in the classification of asphalted surfaces and in the detection of some of their characteristics. This paper explores the state of the art of using remote sensing techniques for monitoring damaged pavements and some typical spectral profiles of various asphalt pavements in Cyprus area acquired using the SVC1024 field spectroradiometer.

  7. Utilization of recycled asphalt concrete with warm mix asphalt and cost-benefit analysis.

    PubMed

    Oner, Julide; Sengoz, Burak

    2015-01-01

    The asphalt paving industries are faced with two major problems. These two important challenges are generated with an increase in demand for environmentally friendly paving mixtures and the problem of rapidly rising raw materials. Recycling of reclaimed asphalt pavement (RAP) is a critical necessity to save precious aggregates and reduce the use of costly bitumen. Warm Mix Asphalt (WMA) technology provides not only the option of recycling asphalt pavement at a lower temperature than the temperature maintained in hot mixtures but also encourages the utilization of RAP and therefore saves energy and money. This paper describes the feasibility of utilizing three different WMA additives (organic, chemical and water containing) at recommended contents with different percentages of RAP. The mechanical properties and cost-benefit analysis of WMA containing RAP have been performed and compared with WMA without RAP. The results indicated that, 30%, 10% and 20% can be accepted as an optimum RAP addition related to organic, chemical and water containing additives respectively and organic additive with 30% RAP content has an appreciable increase in tensile strength over the control mix. It was also concluded that the RAP with WMA technology is the ability to reduce final cost compared to HMA and WMA mixtures. PMID:25574851

  8. Utilization of recycled asphalt concrete with warm mix asphalt and cost-benefit analysis.

    PubMed

    Oner, Julide; Sengoz, Burak

    2015-01-01

    The asphalt paving industries are faced with two major problems. These two important challenges are generated with an increase in demand for environmentally friendly paving mixtures and the problem of rapidly rising raw materials. Recycling of reclaimed asphalt pavement (RAP) is a critical necessity to save precious aggregates and reduce the use of costly bitumen. Warm Mix Asphalt (WMA) technology provides not only the option of recycling asphalt pavement at a lower temperature than the temperature maintained in hot mixtures but also encourages the utilization of RAP and therefore saves energy and money. This paper describes the feasibility of utilizing three different WMA additives (organic, chemical and water containing) at recommended contents with different percentages of RAP. The mechanical properties and cost-benefit analysis of WMA containing RAP have been performed and compared with WMA without RAP. The results indicated that, 30%, 10% and 20% can be accepted as an optimum RAP addition related to organic, chemical and water containing additives respectively and organic additive with 30% RAP content has an appreciable increase in tensile strength over the control mix. It was also concluded that the RAP with WMA technology is the ability to reduce final cost compared to HMA and WMA mixtures.

  9. Utilization of Recycled Asphalt Concrete with Warm Mix Asphalt and Cost-Benefit Analysis

    PubMed Central

    Oner, Julide; Sengoz, Burak

    2015-01-01

    The asphalt paving industries are faced with two major problems. These two important challenges are generated with an increase in demand for environmentally friendly paving mixtures and the problem of rapidly rising raw materials. Recycling of reclaimed asphalt pavement (RAP) is a critical necessity to save precious aggregates and reduce the use of costly bitumen. Warm Mix Asphalt (WMA) technology provides not only the option of recycling asphalt pavement at a lower temperature than the temperature maintained in hot mixtures but also encourages the utilization of RAP and therefore saves energy and money. This paper describes the feasibility of utilizing three different WMA additives (organic, chemical and water containing) at recommended contents with different percentages of RAP. The mechanical properties and cost-benefit analysis of WMA containing RAP have been performed and compared with WMA without RAP. The results indicated that, 30%, 10% and 20% can be accepted as an optimum RAP addition related to organic, chemical and water containing additives respectively and organic additive with 30% RAP content has an appreciable increase in tensile strength over the control mix. It was also concluded that the RAP with WMA technology is the ability to reduce final cost compared to HMA and WMA mixtures. PMID:25574851

  10. Cementitious binder from fly ash and other industrial wastes

    SciTech Connect

    Singh, M.; Garg, M.

    1999-03-01

    In this paper, investigations were undertaken to formulate cementitious binder by judicious blending of fly ash with Portland cement as well as by admixing fly ash with calcined phosphogypsum, fluorogypsum, lime sludge, and chemical activators of different finenesses. The effect of addition of calcined clay in these types of binders was studied. Data showed that cementitious binders of high compressive strength and water retentivity can be produced. The strength of masonry mortars increased with the addition of chemical activators. The strength development of binders takes place through formation of ettringite. C-S-H, and C{sub 4}AH{sub 13}. The binders are eminently suitable for partial replacement (up to 25%) of the cement in concrete without any detrimental affect on the strength. The results showed that fly ash can be used in the range from 45% to 70% in formulating these binders along with other industrial wastes to help in mitigating environmental pollution.

  11. [Iron-based Phosphate Binders for ESRD Patients].

    PubMed

    Cozzolino, Mario; Mangano, Michela; Magagnoli, Lorenza; Di Lullo, Luca; Galassi, Andrea; Brancaccio, Diego; Bellasi, Antonio

    2016-01-01

    Several factors influence the choice of phosphate binder for patients, including older age, male gender, post-menopause, diabetes, low bone turnover, vascular/valvular calcification and inflammation. Unlike calcium-based phosphate binders, non-calcium-based phosphate binders, such as sevelamer and lanthanum carbonate, have been able to reduce the progression of bone disease to adynamic bone among patients with CKD. New iron-based phosphate binders are now available. With multiple options available for the reduction of phosphate, the focus has been on agents that do not contain calcium. This is because it is thought that calcium itself functions as a substrate for calcification. PMID:27545638

  12. Performance-based asphalt mixture design methodology

    NASA Astrophysics Data System (ADS)

    Ali, Al-Hosain Mansour

    Today, several State D.O.T.s are being investigating the use of tire rubber with local conventional materials. Several of the ongoing investigations identified potential benefits from the use of these materials, including improvements in material properties and performance. One of the major problems is being associated with the transferability of asphalt rubber technology without appropriately considering the effects of the variety of conventional materials on mixture behavior and performance. Typically, the design of these mixtures is being adapted to the physical properties of the conventional materials by using the empirical Marshall mixture design and without considering fundamental mixture behavior and performance. Use of design criteria related to the most common modes of failure for asphalt mixtures, such as rutting, fatigue cracking, and low temperature thermal cracking have to be developed and used for identifying the "best mixture," in term of performance, for the specific local materials and loading conditions. The main objective of this study was the development of a mixture design methodology that considers mixture behavior and performance. In order to achieve this objective a laboratory investigation able to evaluate mixture properties that can be related to mixture performance, (in terms of rutting, low temperature cracking, moisture damage and fatigue), and simulating the actual field loading conditions that the material is being exposed to, was conducted. The results proved that the inclusion of rubber into asphalt mixtures improved physical characteristics such as elasticity, flexibility, rebound, aging properties, increased fatigue resistance, and reduced rutting potential. The possibility of coupling the traditional Marshall mix design method with parameters related to mixture behavior and performance was investigated. Also, the SHRP SUPERPAVE mix design methodology was reviewed and considered in this study for the development of an integrated

  13. Nanobodies and recombinant binders in cell biology

    PubMed Central

    Helma, Jonas; Cardoso, M. Cristina; Muyldermans, Serge

    2015-01-01

    Antibodies are key reagents to investigate cellular processes. The development of recombinant antibodies and binders derived from natural protein scaffolds has expanded traditional applications, such as immunofluorescence, binding arrays, and immunoprecipitation. In addition, their small size and high stability in ectopic environments have enabled their use in all areas of cell research, including structural biology, advanced microscopy, and intracellular expression. Understanding these novel reagents as genetic modules that can be integrated into cellular pathways opens up a broad experimental spectrum to monitor and manipulate cellular processes. PMID:26056137

  14. Observation of a network structure in asphalt cements

    SciTech Connect

    Rozeveld, J.; Shin, E.E.; Bhurke, A.; Drzal, L.T.

    1996-12-31

    Paving asphalts are often judged and selected based on their rheological behavior at prescribed temperatures or aging response. Asphalts are considered as a colloidal mixture, where clusters of polar, aromatic molecules are dispersed in a less polar solvent. Thus, the extent to which the solvent phase disperses the associating molecules will determine many of the fundamental asphalt properties. Asphalts are typically divided into four major groups, namely: asphaltenes, resins, aromatics, ans saturates. Asphaltenes are the highest molecular weight group and constitute {approximately}25% of the total asphalt. Resins are very polar in nature and act as a dispersing agent or peptisers for the asphaltenes. The solvent or oily phase (aromatics and saturates) are the lightest molecular weight group and are the bulk of the total asphalt (40-50%). The dispersion of the asphaltenes within the oily solvent is an important property and has been studied by separation and titration methods. In this study, asphalt cements were examined using an Environmental Scanning Electron Microscopy (ESEM) (ElectroScan 2020), and confocal Laser Scanning Microscope (LSM) (Zeiss 10).

  15. High temperature intermetallic binders for HVOF carbides

    SciTech Connect

    Shaw, K.G.; Gruninger, M.F.; Jarosinski, W.J.

    1994-12-31

    Gas turbines technology has a long history of employing the desirable high temperature physical attributes of ceramic-metallic (cermet) materials. The most commonly used coatings incorporate combinations of WC-Co and Cr{sub 3}C{sub 2}-NiCr, which have also been successfully utilized in other non-turbine coating applications. Increased turbine operating temperatures and other high temperature service conditions have made apparent the attractive notion of increasing the temperature capability and corrosion resistance of these coatings. In this study the intermetallic binder NiAl has been used to replace the cobalt and NiCr constituents of conventional WC and Cr{sub 3}C{sub 2} cermet powders. The composite carbide thermal spray powders were fabricated for use in the HVOF coating process. The structure of HVOF deposited NiAl-carbide coatings are compared directly to the more familiar WC-Co and Cr{sub 3}C{sub 2}-NiCr coatings using X-ray diffraction, back-scattered electron imaging (BEI) and electron dispersive spectroscopy (EDS). Hardness variations with temperature are reported and compared between the NiAl and Co/NiCr binders.

  16. Evolution of geopolymer binders: a review

    NASA Astrophysics Data System (ADS)

    Nuruddin, M. F.; Malkawi, A. B.; Fauzi, A.; Mohammed, B. S.; Almattarneh, H. M.

    2016-06-01

    This study aimed to present the current state of research about the terminology, chemical reactions, mechanisms, and microstructure modelling of geopolymer binders. Modelling the structure of the geopolymerization products is essential for controlling the product properties. The currently available models have shown some limitations in determining the rate of geopolymerization and setting time of the gel. There is a need for deeper knowledge regarding the physicochemical analysis of geopolymer binders. Most of the available models have used pure material like metakaolin; however, the less pure materials are expected to have different mechanisms. The FTIR and MAS-NMR analysis are considered as effective tools in providing information on the molecular deviations during geopolymerization. However, XRD analysis is not effective because most of the changes take place in amorphous phases. Also, the role of the iron oxides and some of the other impurities still not clear where none of the previous method of investigation can be used to detect the molecular changes of the iron compounds. This issue is very relevant hence the iron oxides are existed in substantial amounts in most of the waste materials that are suitable to be used as geopolymer source materials.

  17. HP-GPC characterization of asphalt and modified asphalts from gulf countries and their relation to performance based properties

    SciTech Connect

    Wahhab, H.I.A.; Ali, M.F.; Asi, I.M.; Dubabe, I.A.

    1996-12-31

    Asphalt producing refineries in the Gulf countries include Ras Tanura and Riyadh (Saudi Arabia), Al-Ahmadi (Kuwait), and BAPCO (Bahrain). Riyadh and Ras Tanura refineries are located in the central and eastern Saudi Arabia respectively. Arabian light crude oil is used to produce 2000 to 3000 tons of asphalt per day using vacuum distillation, air blowing and grade blending techniques to produce 60/70 penetration grade asphalts in each of these two Saudi refineries. All of the asphalt cement used in Saudi Arabia, Qatar and parts of the United Arab Emirates is supplied by Riyadh and Ras Tanura refineries. Al-Ahmadi refinery supplies all of the asphalt cement needed for construction in the state of Kuwait. Ratwi-Burgan crude off mix is used to produce 750 to 1000 tons of asphalt per day using vacuum distillation and air blowing processes. This study was initiated to evaluate different locally available polymers in order to identify potential polymers to modify asphalts to satisfy the performance requirements in the Gulf countries environmental conditions.

  18. 46 CFR 308.544 - Facultative binder, Form MA-315.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Facultative binder, Form MA-315. 308.544 Section 308.544 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Iii-Facultative War Risk Cargo Insurance § 308.544 Facultative binder, Form...

  19. 7 CFR 29.6126 - Binder (B Group).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... over in length. Uniformity, 90 percent; injury tolerance, 10 percent. B2 Fair Quality Binder. Medium... percent; injury tolerance, 20 percent. B3 Low Quality Binder. Medium, ripe, firm, semielastic,...

  20. 46 CFR 308.203 - Amount insured under interim binder.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Amount insured under interim binder. 308.203 Section 308.203 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Protection and Indemnity Insurance § 308.203 Amount insured under interim binder....

  1. 46 CFR 308.544 - Facultative binder, Form MA-315.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Facultative binder, Form MA-315. 308.544 Section 308.544 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Iii-Facultative War Risk Cargo Insurance § 308.544 Facultative binder, Form...

  2. Characterizing and modeling organic binder burnout from green ceramic compacts

    SciTech Connect

    Ewsuk, K.G.; Cesarano, J. III; Cochran, R.J.; Blackwell, B.F.; Adkins, D.R.

    1995-09-01

    New characterization and computational techniques have been developed to evaluate and simulate binder burnout from pressed powder compacts. Using engineering data and a control volume finite element method (CVFEM) thermal model, a nominally one dimensional (1-D) furnace has been designed to test, refine, and validate computer models that simulate binder burnout assuming a 1-D thermal gradient across the ceramic body during heating. Experimentally, 1-D radial heat flow was achieved using a rod-shaped heater that directly heats the inside surface of a stack of ceramic annuli surrounded by thermal insulation. The computational modeling effort focused on producing a macroscopic model for binder burnout based on continuum approaches to heat and mass conservation for porous media. Two increasingly complex models have been developed that predict the temperature and mass of a porous powder compact as a function of time during binder burnout. The more complex model also predicts the pressure within a powder compact during binder burnout. Model predictions are in reasonably good agreement with experimental data on binder burnout from a 57--65% relative density pressed powder compact of a 94 wt% alumina body containing {approximately}3 wt% binder. In conjunction with the detailed experimental data from the prototype binder burnout furnace, the models have also proven useful for conducting parametric studies to elucidate critical i-material property data required to support model development.

  3. Polyorganosilazane preceramic binder development for reaction bonded silicon nitride composites

    SciTech Connect

    Mohr, D.L.; Starr, T.L. )

    1992-11-01

    This study has examined the use of two commercially available polyorganosilazanes for application as preceramic binders in a composite composed of silicon carbide fibers in a reaction bonded silicon nitride (RBSN) matrix. Ceramic monolithic and composite samples were produced. Density of monolithic and whisker reinforced RBSN samples containing the polysilazane binder was increased. Mercury intrusion porosimetry revealed a significant decrease in the pore sizes of samples containing a polyorganosilazane binder. Electron micrographs of samples containing the preceramic binder looked similar to control samples containing no precursor. Overall, incorporation of the polysilazane into monolithic and whisker reinforced samples resulted in significantly increased density and decreased porosity. Nitriding of the RBSN was slightly retarded by addition of the polysilazane binder. Samples with the preceramic binders contained increased contents of [alpha] versus [beta]-silicon nitride which may be due to interaction of hydrogen evolved from polysilazane pyrolysis with the nitriding process. Initial efforts to produce continuous fiber reinforced composites via this method have not realized the same improvements in density and porosity which have been observed for monolithic and whisker reinforced samples. Further, the addition of perceramic binder resulted in a more brittle fracture morphology as compared to similar composites made without the binder.

  4. Polyorganosilazane preceramic binder development for reaction bonded silicon nitride composites

    SciTech Connect

    Mohr, D.L.; Starr, T.L.

    1992-11-01

    This study has examined the use of two commercially available polyorganosilazanes for application as preceramic binders in a composite composed of silicon carbide fibers in a reaction bonded silicon nitride (RBSN) matrix. Ceramic monolithic and composite samples were produced. Density of monolithic and whisker reinforced RBSN samples containing the polysilazane binder was increased. Mercury intrusion porosimetry revealed a significant decrease in the pore sizes of samples containing a polyorganosilazane binder. Electron micrographs of samples containing the preceramic binder looked similar to control samples containing no precursor. Overall, incorporation of the polysilazane into monolithic and whisker reinforced samples resulted in significantly increased density and decreased porosity. Nitriding of the RBSN was slightly retarded by addition of the polysilazane binder. Samples with the preceramic binders contained increased contents of {alpha} versus {beta}-silicon nitride which may be due to interaction of hydrogen evolved from polysilazane pyrolysis with the nitriding process. Initial efforts to produce continuous fiber reinforced composites via this method have not realized the same improvements in density and porosity which have been observed for monolithic and whisker reinforced samples. Further, the addition of perceramic binder resulted in a more brittle fracture morphology as compared to similar composites made without the binder.

  5. Development of Silane Hydrolysate Binder for Thermal-Control Coatings

    NASA Technical Reports Server (NTRS)

    Patterson, W. J.

    1983-01-01

    Technical report describes theoretical and experimental development of methyltriethoxysilane (MTES) hydrolysate binder for white, titanium dioxidepigmented thermal-control coatings often needed on satellites. New coating is tougher and more abrasion-resistant than conventional coating, S-13G, which comprises zinc oxide in hydroxyl-therminated dimethylsiloxane binder.

  6. Environmentally Friendly Geopolymeric Binders Made with Perlite

    NASA Astrophysics Data System (ADS)

    Erdogan, S. T.

    2011-12-01

    Production of Portland cement (PC), the ubiquitous binding material for construction works, is responsible for 5-10 % of all anthropogenic CO2 emissions. Nearly half of these emissions arise from the decomposition of calcareous raw materials, and the other half from kiln fuel combustion and cement clinker grinding operations. As such, PC production contributes significantly to global warming and climate change. Lately, there have been efforts to develop alternative binders with lower associated green house gas emissions. An important class of such binders is geopolymers, formed by activating natural or waste materials with suitable alkaline or acidic solutions. These binders have very low CO2 emissions from grinding of the starting material, and some from the production of the activating chemical. The total CO2 emission from carefully formulated mixtures can be as low as 1/5th - 1/10th of those of Portland cement concrete mixtures with comparable properties. While use of industrial wastes is environmentally preferable, the variability of their chemical compositions over time makes their use difficult. Use of natural materials depletes resources but can have more consistent properties and can be more easily accepted. Perlite is a volcanic aluminosilicate glass abundant in Turkey, China, Japan, the US and several EU countries. It has been used in its expanded form, for horticulture, for insulation, and for producing lightweight concrete. Turkish perlites contain more than 70 % SiO2, and have a SiO2/Al2O3 ratio of ~5.5. This study shows that ground perlite can be mixed with alkaline activators like sodium hydroxide or sodium silicate to yield mortars with strengths comparable to those of portland cement mortars. Strength gain is slower than with PC mixtures at room temperature but adequate ultimate strength can be achieved with curing at slightly elevated temperatures in 24 h or less. Since perlite is natural, perlite geopolymers can have environmental, energetic, and

  7. Recovery and reuse of asphalt roofing waste burning of asphalt roofing waste

    SciTech Connect

    Zolnick, E.L.; Markus, A.R.; Seigfried, J.N.; Powers, T.J.; Shepherd, P.B.; Graziano, G.J.; Battles, R.L.

    1986-09-15

    The research described in this report was designed to determine the general feasibility and specific requirements for burning asphalt roofing waste and recovering the energy resource as steam. The study combined technical market research with test burning in a three-task program to identify how to use burning as a means for reocvering the 7 x 10/sup 13/ Btu in roofing waste landfilled annually.

  8. Development of a green binder system for paper products

    PubMed Central

    2013-01-01

    Background It is important for industries to find green chemistries for manufacturing their products that have utility, are cost-effective and that protect the environment. The paper industry is no exception. Renewable resources derived from plant components could be an excellent substitute for the chemicals that are currently used as paper binders. Air laid pressed paper products that are typically used in wet wipes must be bound together so they can resist mechanical tearing during storage and use. The binders must be strong but cost-effective. Although chemical binders are approved by the Environmental Protection Agency, the public is demanding products with lower carbon footprints and that are derived from renewable sources. Results In this project, carbohydrates, proteins and phenolic compounds were applied to air laid, pressed paper products in order to identify potential renewable green binders that are as strong as the current commercial binders, while being organic and renewable. Each potential green binder was applied to several filter paper strips and tested for strength in the direction perpendicular to the cellulose fibril orientation. Out of the twenty binders surveyed, soy protein, gelatin, zein protein, pectin and Salix lignin provided comparable strength results to a currently employed chemical binder. Conclusions These organic and renewable binders can be purchased in large quantities at low cost, require minimal reaction time and do not form viscous solutions that would clog sprayers, characteristics that make them attractive to the non-woven paper industry. As with any new process, a large-scale trial must be conducted along with an economic analysis of the procedure. However, because multiple examples of “green” binders were found that showed strong cross-linking activity, a candidate for commercial application will likely be found. PMID:23531016

  9. 12. VIEW NORTH, ACROSS DECK CENTER AREA SHOWING ASPHALT AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW NORTH, ACROSS DECK CENTER AREA SHOWING ASPHALT AND NORTH SIDE GUARD WALL - Route 1 Extension, South Street Viaduct, Spanning Conrail & Wheeler Point Road at South Street, Newark, Essex County, NJ

  10. 4. LOOKING SOUTHWEST AT LATTICED GUARDRAIL, DIAGONALS, ASPHALT DECK AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. LOOKING SOUTHWEST AT LATTICED GUARDRAIL, DIAGONALS, ASPHALT DECK AND LACED ANGLES ON VERTICALS - Wayne County Bridge No. 122, Spanning West Fork Whitewater River at Main Street, Milton, Wayne County, IN

  11. 5. VIEW OF SECOND ELEVATOR WITH WOODFRAME HEADHOUSE AND ASPHALTIC ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF SECOND ELEVATOR WITH WOOD-FRAME HEADHOUSE AND ASPHALTIC SIDING, LOOKING WEST. - Lockport DuPage Farmer's Elevator Company Grain Elevator, South of Romeoville Road, Lockport, Will County, IL

  12. Hot in-place recycling of asphalt concrete. Final report

    SciTech Connect

    Button, J.W.; Little, D.N.; Estakhri, C.K.; Mason, L.S.

    1994-01-01

    ;Contents: Hot in place recycling processes and equipment; HIPR as a tool for asphalt pavement rehabilitation; Mixture design for HIPR processes; Relative performance of HIPR pavements; Guidelines for effective use of HIPR; and Conclusions and recommendations.

  13. Laboratory evaluation of microwave-heated asphalt pavement materials

    SciTech Connect

    Al-Ohaly, A.A.

    1987-01-01

    The potential use of microwave energy to heat asphalt mixtures and pavements has begun attracting attention. Microwave heating is rapid, deep and uniform. With microwaves, heat is generated by the treated material under the excitation of an alternating electromagnetic field caused by the passing microwaves. Some materials such as water heat very well with microwaves, while others such as Teflon do not. Asphalt cement is similar to Teflon, but many aggregates seem to possess favorable microwave heating properties. This thesis focuses on pavement materials and their interaction with microwave energy as a heating method. The interaction between asphalt-pavement materials and the applied microwave energy was evaluated in two phases. First, the effect of microwaves on some properties of virgin and recycled mixtures was investigated. Potential benefits to adhesion and water-stripping resistance of asphalt film to aggregate are promising but need further investigation. Secondly, the effect of several mixture variables on microwave heating efficiency was also studied.

  14. Comprehensive research program: Wind resistance of asphalt shingles

    SciTech Connect

    Jones, J.E.; Metz, R.E.

    1999-07-01

    This paper describes the Asphalt Roofing Manufacturers Association's comprehensive research program which has resulted in a validated wind load model that can be used to calculate the uplift pressure on asphalt shingles as a function of approach wind velocities and other wind and building conditions. Also, a tab uplift resistance test method has been developed to measure the ability of asphalt shingles to withstand the imposed pressures due to the wind. In combination, the results of these two efforts provide the shingle manufacturers with the methodology to evaluate and improve their products. The results are not only of interest to the roofing manufacturers, but also to contractors, code officials, insurance companies, roofing specifiers and other professionals in the roofing industry. The results of this work should provide building owners and homeowners with high performance asphalt shingles for extreme wind conditions.

  15. Synthesis and characterization of activated carbon from asphalt

    NASA Astrophysics Data System (ADS)

    Kandah, Munther Issa; Shawabkeh, Reyad; Al-Zboon, Mahmoud Ar'ef

    2006-11-01

    Asphalt (cheap and available in huge amount in Jordan) was converted into activated carbon powder by chemical treatment with sulphuric and nitric acids at 450 °C. The final product was characterized and found effective as adsorbent material. Its cation exchange capacity reaches 191.2 meq/100-g carbons when treated with 30 wt% acid/asphalt ratio without airflow rate injection and 208 meq/100-g carbons when 6.5 ml air/min was injected into the surface of the asphalt during activation at the same acid/asphalt weight ratio of 30 and temperature 450 °C. The zero point of charge for this product was found to be stable at pH value around 3 in the range of initial pH between 3 and 10.

  16. The wind resistance of asphalt roofing shingles

    NASA Astrophysics Data System (ADS)

    Dixon, Craig Robert

    Asphalt shingle roofing is the leading cause of hurricane wind-related insured losses in residential buildings. Damage statistics generated from recent hurricanes indicate shingle roofs sustain damage in wind velocities below design-level with damage frequency increasing with shingle roof age. The objective of this dissertation is the identification of primary mechanisms triggering the failure of shingle roof systems in wind. The research goal is to reduce future shingle roof wind damage and improve our ability to predict asphalt shingle wind resistance. Five studies comprising this dissertation addressed the adhesive consistency and strength of aged asphalt shingles, system-level wind resistance, and the load model underpinning the ASTM D7158 wind test standard. The most significant and unexpected finding was partially unsealed shingles on field, hip, and ridge locations on Florida and Texas homes. Location on the shingle's sealant strip where unsealed and failure mode were consistent at each location. Total quantity of partially unsealed shingles in the field of the roof significantly increased with age, aligning with damage statistics. Full-scale wind tunnel tests demonstrate partially unsealed shingles are more vulnerable than fully sealed due to increased distributed force on sealant strip and concentrated force at the adhered and non-adhered interface. Uplift resistance was measured in artificially and naturally aged shingles. For artificially aged shingles, one of three products evaluated had statistically significant decreases in mean uplift resistance as exposure time increased. However, resistance was above design-level at all exposure test intervals. Naturally aged shingles also had resistance above design-level. Combined results demonstrate that reduced uplift capacity can occur, but high initial bond strength promotes long-term uplift resistance. Wind loads exerted on the shingles sealant strip load path were directly measured on fully sealed and

  17. User's guide: Cold-mix recycling of asphalt concrete pavements. Final report

    SciTech Connect

    Shoenberger, J.E.

    1992-09-01

    This guide provides the technical information required to implement the application of cold-mix recycling of asphalt concrete pavements. Included are details on areas on application, benefits/advantages, limitations/disadvantages, and costs associated with this technology. Information is provided on two demonstration sites at Fort Gillem, Georgia, and Fort Leavenworth, Kansas. Also provided is information concerning funding, procurement, maintenance, and performance monitoring. A fact sheet on recycling, contract specification example, and references are provided in the appendixes.... Asphalt pavement recycling, Emulsified asphalt cement, Cold milling, In-place cold-mix asphalt recycling, Cold-mix asphalt recycling, Recycling of asphalt.

  18. Value-added utilisation of recycled concrete in hot-mix asphalt.

    PubMed

    Wong, Yiik Diew; Sun, Darren Delai; Lai, Dickson

    2007-01-01

    The feasibility of partial substitution of granite aggregate in hot-mix asphalt (HMA) with waste concrete aggregate was investigated. Three hybrid HMA mixes incorporating substitutions of granite fillers/fines with 6%, 45% untreated, and 45% heat-treated concrete were evaluated by the Marshall mix design method; the optimum binder contents were found to be 5.3%, 6.5% and 7.0% of grade Pen 60/70 bitumen, respectively. All three hybrid mixes satisfied the Marshall criteria of the Singapore Land Transport Authority (LTA) W3B wearing course specification. The hybrid mix with 6% concrete fillers gave comparable resilient modulus and creep resistance as the conventional W3B mix, while hybrid mixes with higher concrete substitutions achieved better performance. X-ray diffraction (XRD) showed the distinct presence of free lime in the heat-treated concrete, while the scanning electron microscope (SEM) provided an in-depth perspective of the concrete grains in the HMA matrix. The results suggest feasible use of waste concrete as partial aggregate substitution in HMA.

  19. Value-added utilisation of recycled concrete in hot-mix asphalt

    SciTech Connect

    Wong, Yiik Diew; Sun, Darren Delai . E-mail: ddsun@ntu.edu.sg; Lai, Dickson

    2007-07-01

    The feasibility of partial substitution of granite aggregate in hot-mix asphalt (HMA) with waste concrete aggregate was investigated. Three hybrid HMA mixes incorporating substitutions of granite fillers/fines with 6%, 45% untreated, and 45% heat-treated concrete were evaluated by the Marshall mix design method; the optimum binder contents were found to be 5.3%, 6.5% and 7.0% of grade Pen 60/70 bitumen, respectively. All three hybrid mixes satisfied the Marshall criteria of the Singapore Land Transport Authority (LTA) W3B wearing course specification. The hybrid mix with 6% concrete fillers gave comparable resilient modulus and creep resistance as the conventional W3B mix, while hybrid mixes with higher concrete substitutions achieved better performance. X-ray diffraction (XRD) showed the distinct presence of free lime in the heat-treated concrete, while the scanning electron microscope (SEM) provided an in-depth perspective of the concrete grains in the HMA matrix. The results suggest feasible use of waste concrete as partial aggregate substitution in HMA.

  20. The use of waste materials in asphalt concrete mixtures.

    PubMed

    Tuncan, Mustafa; Tuncan, Ahmet; Cetin, Altan

    2003-04-01

    The purpose of this study was to investigate (a) the effects of rubber and plastic concentrations and rubber particle sizes on properties of asphalt cement, (b) on properties of asphalt concrete specimens and (c) the effects of fly ash, marble powder, rubber powder and petroleum contaminated soil as filler materials instead of stone powder in the asphalt concrete specimens. One type of limestone aggregate and one penetration-graded asphalt cement (75-100) were used. Three concentrations of rubber and plastic (i.e. 5%, 10% and 20% of the total weight of asphalt cement), three rubber particle sizes (i.e. No. 4 [4.75mm] - 20 [0.85 mm], No. 20 [0.85mm] - 200 [0.075mm] and No. 4 [4.75mm] - 200 [0.075mm]) and one plastic particle size (i.e. No. 4 [4.75mm] - 10 [2.00mm]) were also used. It was found that while the addition of plastic significantly increased the strength of specimens, the addition of rubber decreased it. No. 4 [4.75mm] - 200 [0.075mm] rubber particles showed the best results with respect to the indirect tensile test. The Marshall stability and indirect tensile strength properties of plastic modified specimens increased. Marble powder and fly ash could be used as filler materials instead of stone powder in the asphalt concrete pavement specimens.

  1. X-ray phase determination of solid paraffins in asphalts

    SciTech Connect

    Biktimirova, T.G.; Aleksandrova, S.L.; Fryazinov, V.V.

    1984-03-01

    This article discusses the attempt to increase the sensitivity of the x-ray phase analysis and to broaden the field of its application in determining the content of paraffins in petroleum asphalts and residual stocks from various raw materials. Samples were prepared by blending technical-grade paraffin wax with a paraffin-free asphalt. The influence of the cooling time on the intensity of the paraffin lines was determined for the various asphalt samples. In order to improve the reproducibility of the line intensity, 1% microcrystalline wax with a known content of paraffins was added to each reference sample. Artificial mixtures of paraffins with model asphalts having various group compositions were prepared in order to determine the influence of the composition of the various asphalts on the intensity of the paraffin reflections under the preparation conditions (heating and cooling). It is established that with increasing takeoff of distillate in the vacuum distillation of atmospheric resids, or in the course of oxidation of residual stocks to produce asphalts, the paraffin content drops. Includes 2 tables.

  2. Bacteria and asphalt stripping. Final report, December 1983-August 1987

    SciTech Connect

    Ramamurti, K.; Jayaprakash, G.P.

    1987-08-01

    Major types of bituminous pavement distress were rutting, cracking (longitudinal, transverse, and alligator) and stripping. The rubble and loosely bound material contained bacteria. The deterioration lessened upward from the pavement-soil interface. The soil appears to be the prime source of the bacteria. Most of the bacterial cells were sausage shaped with polar flagellation. They appeared to belong to the genus Pseudomonas, which is a known user of asphaltic hydrocarbons. Cocci-type bacteria and a virus were also noted. Increasing the density of some asphaltic concrete and strengthening the bond between aggregate and asphalt are considered as the preferred alternatives to using chemical biocides. Anything to reduce pavement cracking would help. Adding lime to asphalt mixes may be one effective means of improving aggregate-asphalt bond and controlling biodeterioration. Lime stabilization of soils under asphalt pavements may provide an added protection against bacterial attack by rendering the soil more hostile to bacterial habitat. Full-depth hot-mix recycling would be more effective than partial-depth recycling in retarding bacterial decay at cracks.

  3. Application of Common Mid-Point Method to Estimate Asphalt

    NASA Astrophysics Data System (ADS)

    Zhao, Shan; Al-Aadi, Imad

    2015-04-01

    3-D radar is a multi-array stepped-frequency ground penetration radar (GPR) that can measure at a very close sampling interval in both in-line and cross-line directions. Constructing asphalt layers in accordance with specified thicknesses is crucial for pavement structure capacity and pavement performance. Common mid-point method (CMP) is a multi-offset measurement method that can improve the accuracy of the asphalt layer thickness estimation. In this study, the viability of using 3-D radar to predict asphalt concrete pavement thickness with an extended CMP method was investigated. GPR signals were collected on asphalt pavements with various thicknesses. Time domain resolution of the 3-D radar was improved by applying zero-padding technique in the frequency domain. The performance of the 3-D radar was then compared to that of the air-coupled horn antenna. The study concluded that 3-D radar can be used to predict asphalt layer thickness using CMP method accurately when the layer thickness is larger than 0.13m. The lack of time domain resolution of 3-D radar can be solved by frequency zero-padding. Keywords: asphalt pavement thickness, 3-D Radar, stepped-frequency, common mid-point method, zero padding.

  4. APPLICATION OF LOW TEMPERATU RE PROPERTIES IMPROVEMENT ASPHALT TO REPAIRE WORK OF RO CK FILL DAM WITH ASPHALT FACING

    NASA Astrophysics Data System (ADS)

    Shimazaki, Masaru; Tsunoo, Takashi; Kasahara, Atsushi

    The low temperature properties improvement asphalt that is no decreasing the transformation follow and the stress relaxation properties at the low temperature was developed. It aimed at properties of PG64-28 (lowest temperature 28 degree C and maximum temperature 64 degree C that was able to be used) from PG (Performance Grade) of mix design method SUPERPAVE (Superior Performance Pavement) of new road-building plan SHRP (Strategic Highway Research Program) in the United States when developing. When the repair work of the rock fill dam with asphalt facing located in Kyogoku-cho Abuta-gun Hokkaido was planned, the applicability of the developed asphalt was verified. As for the verification outcome and the developed asphalt, it was proven that it was applied to the repair construction, and there was no problem in manufacturing and construction.

  5. Replacement of asphalt in glass-mat roofing shingles. Final report, March 1980-March 1982

    SciTech Connect

    Bastian, E.J. Jr.; McCandlish, E.F.K.; Sieling, F.W.

    1982-05-01

    Up to 50% of the asphalt now used in glass-mat shingles may be replaceable by increasing the mineral filler content and/or extending the asphalt with elemental sulfur. Highly filled, lab-made shingles containing asphalt flux perform acceptably in fire tests, slide tests, blister tests, granule adhesion, and freeze-thaw cracking tests. They have high stain and scuff potential and are too limp for convenient application around 110/sup 0/F. Lab-made shingles containing asphalt saturant are satisfactory in most respects, but they are still too limp for high temperature application. Various methods to stiffen highly filled shingles were tried. The most promising method is the use of two lightweight glass mats, laminated together with asphalt. Shingles made in this way have handling properties superior to conventional shingles and are economically feasible. In the area of replacement of asphalt with sulfur, five small-scale plant trials produced shingles which, after a year of outdoor exposure, are satisfactory. On the basis of preliminary measurements, no important difference in tensile or flexural properties between asphalt and sulfur/asphalt shingles is expected. In Weather-Ometer tests, sulfur/asphalt tends to have lower durability than conventional coating. This is confirmed by outside weathering of sulfur/asphalt films. By choosing the correct asphalt softening point and correct filler level, sulfur/asphalt/filler can have equal durability to conventional asphalt/filler combinations.

  6. 40 CFR 436.60 - Applicability; description of the asphaltic mineral subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asphaltic mineral subcategory. 436.60 Section 436.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY Asphaltic Mineral Subcategory § 436.60 Applicability; description of the...

  7. 40 CFR 436.60 - Applicability; description of the asphaltic mineral subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asphaltic mineral subcategory. 436.60 Section 436.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY Asphaltic Mineral Subcategory § 436.60 Applicability; description of the...

  8. 40 CFR 436.60 - Applicability; description of the asphaltic mineral subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asphaltic mineral subcategory. 436.60 Section 436.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY Asphaltic Mineral Subcategory § 436.60 Applicability; description of the...

  9. Asphalt Roofing Shingles Into Energy Project Summary Report

    SciTech Connect

    Jameson, Rex, PE

    2008-04-28

    Based on a widely cited September, 1999 report by the Vermont Agency of Natural Resources, nearly 11 million tons of asphalt roofing shingle wastes are produced in the United States each year. Recent data suggests that the total is made up of about 9.4 million tons from roofing tear-offs and about 1.6 million tons from manufacturing scrap. Developing beneficial uses for these materials would conserve natural resources, promote protection of the environment and strengthen the economy. This project explored the feasibility of using chipped asphalt shingle materials in cement manufacturing kilns and circulating fluidized bed (CFB) boilers. A method of enhancing the value of chipped shingle materials for use as fuel by removing certain fractions for use as substitute raw materials for the manufacture of new shingles was also explored. Procedures were developed to prevent asbestos containing materials from being processed at the chipping facilities, and the frequency of the occurrence of asbestos in residential roofing tear-off materials was evaluated. The economic feasibility of each potential use was evaluated based on experience gained during the project and on a review of the well established use of shingle materials in hot mix asphalt. This project demonstrated that chipped asphalt shingle materials can be suitable for use as fuel in circulating fluidized boilers and cement kilns. More experience would be necessary to determine the full benefits that could be derived and to discover long term effects, but no technical barriers to full scale commercial use of chipped asphalt shingle materials in these applications were discovered. While the technical feasibility of various options was demonstrated, only the use of asphalt shingle materials in hot mix asphalt applications is currently viable economically.

  10. 46 CFR 308.303 - Amounts insured under interim binder.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... INSURANCE Second Seamen's War Risk Insurance § 308.303 Amounts insured under interim binder. The amounts insured are the amounts specified in the Second Seamen's War Risk Policy (1955) or as modified by...

  11. 46 CFR 308.303 - Amounts insured under interim binder.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... INSURANCE Second Seamen's War Risk Insurance § 308.303 Amounts insured under interim binder. The amounts insured are the amounts specified in the Second Seamen's War Risk Policy (1955) or as modified by...

  12. 46 CFR 308.303 - Amounts insured under interim binder.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... INSURANCE Second Seamen's War Risk Insurance § 308.303 Amounts insured under interim binder. The amounts insured are the amounts specified in the Second Seamen's War Risk Policy (1955) or as modified by...

  13. 46 CFR 308.303 - Amounts insured under interim binder.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... INSURANCE Second Seamen's War Risk Insurance § 308.303 Amounts insured under interim binder. The amounts insured are the amounts specified in the Second Seamen's War Risk Policy (1955) or as modified by...

  14. 46 CFR 308.303 - Amounts insured under interim binder.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... INSURANCE Second Seamen's War Risk Insurance § 308.303 Amounts insured under interim binder. The amounts insured are the amounts specified in the Second Seamen's War Risk Policy (1955) or as modified by...

  15. Epitope-Specific Binder Design by Yeast Surface Display.

    PubMed

    Mann, Jasdeep K; Park, Sheldon

    2015-01-01

    Yeast surface display is commonly used to engineer affinity and design novel molecular interaction. By alternating positive and negative selections, yeast display can be used to engineer binders that specifically interact with the target protein at a defined site. Epitope-specific binders can be useful as inhibitors if they bind the target molecule at functionally important sites. Therefore, an efficient method of engineering epitope specificity should help with the engineering of inhibitors. We describe the use of yeast surface display to design single domain monobodies that bind and inhibit the activity of the kinase Erk-2 by targeting a conserved surface patch involved in protein-protein interaction. The designed binders can be used to disrupt signaling in the cell and investigate Erk-2 function in vivo. The described protocol is general and can be used to design epitope-specific binders of an arbitrary protein. PMID:26060073

  16. Electrochemical performance of Si anode modified with carbonized gelatin binder

    NASA Astrophysics Data System (ADS)

    Jiang, Ying; Mu, Daobin; Chen, Shi; Wu, Borong; Cheng, Kailin; Li, Luyu; Wu, Feng

    2016-09-01

    Gelatin is alternatively adopted as the binder to modify Si anode coupling with its carbonization treatment. The binder can provide good bonding and uniform dispersion of the particles besides its environmental benignancy. Importantly, the carbonized binder containing nitrogen will be advantageous to the electrical conductivity of the electrode. In addition, some spaces are formed in the electrode due to the decomposition and shrinkage of the gelatin binder during heat-treatment, which may facilitate electrolyte penetration and accommodate volume change during cycling. All these merits make contribution to the good electrochemical performance of the modified Si electrode. It exhibits a reversible capacity of 990.3 mA h g-1 after 70 cycles at a current density of 100 mA g-1 and 904 mA h g-1 after 100 cycles at 400 mA g-1.

  17. Research and industrial application of series MJ-compound binders

    SciTech Connect

    Xu, G.; Gao, J.; Xu, Z.

    1997-12-31

    This paper presents a discussion of the series MJ-compound binders studies, which were developed recently, as well as the results of industrial tests and applications. Compared with traditional binders used to produce coal briquettes such as lime, humic acid, clay, etc., the series MJ-compound binders have the advantages of low additive ratio, low price and rich resources, as well as simple production processes and low operational costs. The successful development of the MJ10/MJ11 compound binder and its industrial applications, which uses dry processing and can produce high strength and waterproof coal briquettes, has made great progress in industrial coal briquetting technologies in China. Therefore, it is now possible to produce coal briquettes locally near coal mine areas and to transport them long distance to different consumers.

  18. Development of composite solid propellent using dicyclopentadien binder

    NASA Astrophysics Data System (ADS)

    Bluestone, Stephen Ray

    Through the history of composite solid propellant binders new chemicals are introduced as binders to improve upon the previous generation. Sometimes this is done to improve upon the flaws or shortcomings of a previous binder. Other time it is to meet a new set of requirements desired by industry. Dicyclopentadiene (DCPD) is a hydrocarbon monomer being considered for its potential as a new binder in the composite propellant industry. The binder of a composite solid propellant is arguably the most important feature of the propellant. It is the binder that provides the majority of the structural characteristics of the propellant while also contributing itself as fuel to the combustion process. A binder in composite propellants must also be able to accept the introduction of a large quantity of solid filler; oxidizer, fuel, and other energetic and non-energetic particles. Many of the composite propellants used in industry today have over 80% of their weight composed of non-binder solid or liquid fillers. These requirements must be met by the binder in some form or fashion to produce a propellant able to compete with binders currently in use. When DCPD is polymerized it produces an extremely tough plastic with excellent tensile and impact strength. Experimentation has found that DCPD is able to support a large quantity of solid materials, over 80% weight of the mixture, while still retaining a great portion of its original strength. When compared to another similarly loaded binder currently used in industry, Hydroxyl-Terminated Polybutadiene (HTPB), it was found that DCPD composite propellant had nearly 1.5 times the stress capacity while still exhibiting over 75% of the strain capacity of HTPB based composite propellant. In addition it was also shown that DCPD composite propellant allows for tailoring of its mechanical properties with the addition of plasticizers. The DCPD based composite propellant also exhibits a burning rate nearly twice that HTPB. These factors

  19. Novel Binders and Methods for Agglomeration of Ore

    SciTech Connect

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-12-31

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking. This project has identified several acid-resistant binders and agglomeration procedures that can be used for improving the energy efficiency of heap leaching, by preventing the ''ponding'' and ''channeling'' effects that currently cause reduced recovery and extended leaching cycle times. Methods have also been developed for iron ore processing which are intended to improve the

  20. Specifications and Construction Methods for Asphalt Concrete and Other Plant-Mix Types, 3rd Edition.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    The purpose of this publication is to assist engineers in the analysis, design and control of paving projects that use asphalt concrete and other asphalt plant-mixes. The scope of this new third edition has been enlarged, and changes necessitated by advances in asphalt technology have been incorporated. Chapters I and II and Appendices A and B…

  1. ASPHALT FOR OFF-STREET PAVING AND PLAY AREAS, 3RD EDITION.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    THIS PAMPHLET DISCUSSES THE ALTERNATIVE METHODS, APPLICATIONS, AND TECHNICAL CONSIDERATIONS FOR OFF-STREET PAVING AND PLAY AREAS. OFF-STREET PAVING INCLUDES--(1) ASPHALT-PAVED PARKING AREAS, (2) ROOF DECK PARKING AREAS, (3) ASPHALT-PAVED DRIVEWAYS, (4) ASPHALT-PAVED SERVICE STATION LOTS, AND (5) SIDEWALKS. THE DISCUSSION OF PLAY AREAS…

  2. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Manufacturing (Coating) Operations 2 Table 2 of Subpart AAAAAAA of Part 63 Protection of Environment... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * *...

  3. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Manufacturing (Coating) Operations 2 Table 2 of Subpart AAAAAAA of Part 63 Protection of Environment... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * *...

  4. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Manufacturing (Coating) Operations 2 Table 2 of Subpart AAAAAAA of Part 63 Protection of Environment... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * *...

  5. On the representative volume element of asphalt concrete at low temperature

    NASA Astrophysics Data System (ADS)

    Marasteanu, Mihai; Cannone Falchetto, Augusto; Velasquez, Raul; Le, Jia-Liang

    2016-08-01

    The feasibility of characterizing asphalt mixtures' rheological and failure properties at low temperatures by means of the Bending Beam Rheometer (BBR) is investigated in this paper. The main issue is the use of thin beams of asphalt mixture in experimental procedures that may not capture the true behavior of the material used to construct an asphalt pavement.

  6. 40 CFR 436.60 - Applicability; description of the asphaltic mineral subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asphaltic mineral subcategory. 436.60 Section 436.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY Asphaltic Mineral Subcategory § 436.60 Applicability; description of the asphaltic mineral subcategory....

  7. 40 CFR 436.60 - Applicability; description of the asphaltic mineral subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asphaltic mineral subcategory. 436.60 Section 436.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY Asphaltic Mineral Subcategory § 436.60 Applicability; description of the asphaltic mineral subcategory....

  8. NOVEL BINDERS AND METHODS FOR AGGLOMERATION OF ORE

    SciTech Connect

    S.K. Kawatra; T.C. Eisele; J.A. Gurtler; C.A. Hardison; K. Lewandowski

    2004-04-01

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking.

  9. Binder/HMX interaction in PBX9501 at Elevated Temperatures

    SciTech Connect

    K., S C; M., T C

    2003-10-02

    Plastic bonded explosives (PBX) generally consist of 85 - 95 % by weight energetic material, such as HMX, and 5 - 15 % polymeric binder. Understanding of the structure and morphology at elevated temperatures and pressures is important for predicting of PBX behavior in accident scenarios. The crystallographic behavior of pure HMX has been measured as functions of temperature and grain size. The investigation is extended to the high temperature behavior of PBX 9501 (95% HMX, 2.5 % Estane, 2.5 % BDNPA/F). The results show that the HMX {beta}-phase to {delta}-phase transition in PBX 9501 is similar to that in neat HMX. However, in the presence of the PBX 9501 binder, {delta}-phase HMX readily converts back to {beta}-phase during cooling. Using the same temperature profile, the conversion rate decreases for each subsequent heating and cooling cycle. As observed in earlier experiments, no reverse conversion is observed without the polymer binder. It is proposed that the reversion of {delta}-phase to {beta}-phase is due to changes in the surface molecular potential caused by the influence of the polymer binder on the surface molecules of the {delta}-phase. Upon thermal cycling, the polymer binder segregates from the HMX particles and thus reduces the influence of the binder on the surface molecules. This segregation increases the resistance for the {delta}-phase to {beta}-phase transition, as demonstrated in an aged PBX 9501 material for which the reversion is not observed.

  10. Asphalt mounds and associated biota on the Angolan margin

    NASA Astrophysics Data System (ADS)

    Jones, Daniel O. B.; Walls, Anne; Clare, Michael; Fiske, Mike S.; Weiland, Richard J.; O'Brien, Robert; Touzel, Daniel F.

    2014-12-01

    Release of hydrocarbons from sediments is important in increasing habitat heterogeneity on deep ocean margins. Heterogeneity arises from variation in abiotic and biotic conditions, including changes in substratum, geochemistry, fluid flow, biological communities and ecological interactions. The seepage of heavy hydrocarbons to the seafloor is less well studied than most other cold seep systems and may lead to the formation of asphalt mounds. These have been described from several regions, particularly the Gulf of Mexico. Here, we describe the structure, potential formation and biology of a large asphalt mound province in Block 31SE Angola. A total of 2254 distinct mound features was identified by side-scan sonar, covering a total area of 3.7 km2 of seafloor. The asphalt mounds took a number of forms from small (<0.5 m diameter; 13% observations) mounds to large extensive (<50 m diameter) structures. Some of the observed mounds were associated with authigenic carbonate and active seepage (living chemosynthetic fauna present in addition to the asphalt). The asphalt mounds are seabed accumulations of heavy hydrocarbons formed from subsurface migration and fractionation of reservoir hydrocarbons primarily through a network of faults. In Angola these processes are controlled by subsurface movement of salt structures. The asphalt mounds were typically densely covered with epifauna (74.5% of mounds imaged had visible epifauna) although individual mounds varied considerably in epifaunal coverage. Of the 49 non-chemosynthetic megafaunal taxa observed, 19 taxa were only found on hard substrata (including asphalt mounds), 2 fish species inhabited the asphalt mounds preferentially and 27 taxa were apparently normal soft-sediment fauna. Antipatharians (3.6±2.3% s.e.) and poriferans (2.6±1.9% s.e.) accounted for the highest mean percentage of the observed cover, with actinarians (0.9±0.4% s.e.) and alcyonaceans (0.4±0.2% s.e.) covering smaller proportions of the area

  11. Frequency analysis of stress relaxation dynamics in model asphalts

    NASA Astrophysics Data System (ADS)

    Masoori, Mohammad; Greenfield, Michael L.

    2014-09-01

    Asphalt is an amorphous or semi-crystalline material whose mechanical performance relies on viscoelastic responses to applied strain or stress. Chemical composition and its effect on the viscoelastic properties of model asphalts have been investigated here by computing complex modulus from molecular dynamics simulation results for two different model asphalts whose compositions each resemble the Strategic Highway Research Program AAA-1 asphalt in different ways. For a model system that contains smaller molecules, simulation results for storage and loss modulus at 443 K reach both the low and high frequency scaling limits of the Maxwell model. Results for a model system composed of larger molecules (molecular weights 300-900 g/mol) with longer branches show a quantitatively higher complex modulus that decreases significantly as temperature increases over 400-533 K. Simulation results for its loss modulus approach the low frequency scaling limit of the Maxwell model at only the highest temperature simulated. A Black plot or van Gurp-Palman plot of complex modulus vs. phase angle for the system of larger molecules suggests some overlap among results at different temperatures for less high frequencies, with an interdependence consistent with the empirical Christensen-Anderson-Marasteanu model. Both model asphalts are thermorheologically complex at very high frequencies, where they show a loss peak that appears to be independent of temperature and density.

  12. An Approach for Nonlinear Fatigue Damage Evaluation in Asphalt Pavements

    NASA Astrophysics Data System (ADS)

    Rajbongshi, Pabitra; Thongram, Sonika

    2016-08-01

    Fatigue due to vehicular loads is one of the primary distress mechanisms in asphalt pavements. It happens primarily due to deterioration in asphalt material with load repetitions. Degradation of asphalt material may be evaluated using different parameters. In view of degradation, the incremental damage in a given pavement section would be different for different repetitions, even with same loadings. Therefore, the damage progression becomes nonlinear with repetitions. Accounting such nonlinearity in damage accumulation, and based on different damage evaluation parameters, this paper presents an equivalent approach for fatigue damage evaluation in asphalt pavements. Traditional fatigue equation adopted in mechanistic-empirical pavement design has been used in the present work. Four different criteria, namely number of load repetitions, asphalt stiffness reduction, strain enhancement and fatigue life reduction with repetitions are considered for damage estimation. The proposed approach could estimate same value of nonlinear damage, irrespective of the criteria used. The simplest form of criterion i.e. the number of load repetitions can be used for fatigue performance evaluation. Probabilistically, the damage propagation is also correlated and assessed with the failure probability.

  13. Recovery and reuse of asphalt roofing waste. Final report

    SciTech Connect

    Desai, S.; Graziano, G.; Shepherd, P.

    1984-02-02

    Burning of asphalt roofing waste as a fuel and incorporating asphalt roofing waste in bituminous paving were identified as the two outstanding resource recovery concepts out of ten studied. Four additional concepts might be worth considering under different market or technical circumstances. Another four concepts were rated as worth no further consideration at this time. This study of the recovery of the resource represented in asphalt roofing waste has identified the sources and quantities of roofing waste. About six million cubic yards of scrap roofing are generated annually in the United States, about 94% from removal of old roofing at the job site and the remainder from roofing material production at factories. Waste disposal is a growing problem for manufacturers and contractors. Nearly all roofing waste is hauled to landfills at a considerable expense to roofing contractors and manufacturers. Recovery of the roofing waste resource should require only a modest economic incentive. The asphalt contained in roofing waste represents an energy resource of more than 7 x 10/sup 13/ Btu/year. Another 1 x 10/sup 13/ Btu/year may be contained in field-applied asphalt on commercial building roofs. The two concepts recommended by this study appear to offer the broadest applicability, the most favorable economics, and the highest potential for near-term implementation to reuse this resource.

  14. Aging test results of an asphalt membrane liner

    SciTech Connect

    Buelt, J.L.; Barnes, S.M.

    1983-07-01

    The objective of the asphalt aging study described in this report was to determine the expected performance lifetime of a catalytically airblown asphalt membrane as a seepage barrier for inactive uranium mill tailings. The study, conducted by Pacific Northwest Laboratory for the Department of Energy's Uranium Mill Tailings Remedial Action Program, showed through chemical compatibility tests that the asphalt membrane is well suited for this purpose. The chemical compatibility tests were designed to accelerate the aging reactions in the asphalt and to determine the accelerated aging effect. Higher temperatures and oxygen concentrations proved to be effective acceleration parameters. By infrared spectral analysis, the asphalt was determined to have undergone 7 years of equivalent aging in a 3-month period when exposed to 40/sup 0/C and 1.7 atm oxygen pressure. However, the extent of aging was limited to a maximum penetration of 0.5% of the total liner thickness. It was concluded that the liner could be expected to be effective as a seepage barrier for at least 1000 years before the entire thickness of the liner would be degraded.

  15. 43 CFR 3503.14 - For what areas may I get a permit or lease for asphalt?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... for asphalt? 3503.14 Section 3503.14 Public Lands: Interior Regulations Relating to Public Lands... § 3503.14 For what areas may I get a permit or lease for asphalt? You may get leases for asphalt only on... may not obtain prospecting permits for asphalt....

  16. 43 CFR 3503.14 - For what areas may I get a permit or lease for asphalt?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... for asphalt? 3503.14 Section 3503.14 Public Lands: Interior Regulations Relating to Public Lands... § 3503.14 For what areas may I get a permit or lease for asphalt? You may get leases for asphalt only on... may not obtain prospecting permits for asphalt....

  17. 43 CFR 3503.14 - For what areas may I get a permit or lease for asphalt?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... for asphalt? 3503.14 Section 3503.14 Public Lands: Interior Regulations Relating to Public Lands... § 3503.14 For what areas may I get a permit or lease for asphalt? You may get leases for asphalt only on... may not obtain prospecting permits for asphalt....

  18. 43 CFR 3503.14 - For what areas may I get a permit or lease for asphalt?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... for asphalt? 3503.14 Section 3503.14 Public Lands: Interior Regulations Relating to Public Lands... § 3503.14 For what areas may I get a permit or lease for asphalt? You may get leases for asphalt only on... may not obtain prospecting permits for asphalt....

  19. Test of LOX compatibility for asphalt and concrete runway materials

    NASA Technical Reports Server (NTRS)

    Moyers, C. V.; Bryan, C. J.; Lockhart, B. J.

    1973-01-01

    A literature survey and a telephone canvass of producers and users of LOX is reported which yielded one report of an accident resulting from a LOX spill on asphalt, one discussion of hazardous conditions, and an unreferenced mention of an incident. Laboratory tests using standard LOX impact apparatus yielded reactions with both old and new alphalt, but none with concrete. In the final test, using a larger sample of asphalt, the reaction caused extensive damage to equipment. Initial field experiments using 2-meter square asphalt slabs covered with LOX, conducted during rainy weather, achieved no reaction with plummets, and limited reaction with a blasting cap as a reaction initiator. In a final plummet-initiated test on a dry slab, a violent reaction, which appeared to have propagated over the entire slab surface, destroyed the plummet fixture and threw fragments as far as 48 meters.

  20. Hanford Permanent Isolation Barrier Program: Asphalt technology test plan

    SciTech Connect

    Freeman, H.D.; Romine, R.A.

    1994-05-01

    The Hanford Permanent Isolation Barriers use engineered layers of natural materials to create an integrated structure with backup protective features. The objective of current designs is to develop a maintenance-free permanent barrier that isolates wastes for a minimum of 1000 years by limiting water drainage to near-zero amounts. Asphalt is being used as an impermeable water diversion layer to provide a redundant layer within the overall barrier design. Data on asphalt barrier properties in a buried environment are not available for the required 100-year time frame. The purpose of this test plan is to outline the activities planned to obtain data with which to estimate performance of the asphalt layers.

  1. Asphalt emulsion sealing of uranium mill tailings. 1980 annual report

    SciTech Connect

    Hartley, J.N.; Koehmstedt, P.L; Esterl, D.J.; Freeman, H.D.; Buelt, J.L.; Nelson, D.A.; Elmore, M.R.

    1981-05-01

    Studies of asphalt emulsion sealants conducted by the Pacific Northwest Laboratory have demonstrated that the sealants are effective in containing radon and other potentially hazardous material within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to near background levels. Field tests at the tailings pile in Grand Junction, Colorado, confirmed that an 8-cm admix seal containing 22 wt% asphalt could be effectively applied with a cold-mix paver. Other techniques were successfully tested, including a soil stabilizer and a hot, rubberized asphalt seal that was applied with a distributor truck. After the seals were applied and compacted, overburden was applied over the seal to protect the seal from ultraviolet degradation.

  2. Investigation of Asphalt Mixture Creep Behavior Using Thin Beam Specimens

    NASA Astrophysics Data System (ADS)

    Zofka, Adam; Marasteanu, Mihai; Turos, Mugur

    2008-02-01

    The asphalt pavement layer consists of two or more lifts of compacted asphalt mixture; the top of the layer is also exposed to aging, a factor that significantly affects the mixture properties. The current testing specifications use rather thick specimens that cannot be used to investigate the gradual change in properties with pavement depth. This paper investigates the feasibility of using the 3-point bending test with thin asphalt mixture beams (127×12.7×6.35 mm) to determine the low-temperature creep compliance of the mixtures. Several theoretical and semi-empirical models, from the theory of composites, are reviewed and evaluated using numerical and experimental data. Preliminary results show that this method can be used for low-temperature mixture characterization but several crucial factors need further inspection and interpretation.

  3. Asphalt emulsion sealing of uranium mill tailings. 1979 annual report

    SciTech Connect

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-06-01

    Uranium mill tailings are a source of low-level radiation and radioactive materials that may be released into the environment. Stabilization or disposal of these tailings in a safe and environmentally sound way is necessary to minimize radon exhalation and other radioactive releases. One of the most promising concepts for stabilizing uranium tailings is being investigated at the Pacific Northwest Laboratory: the use of asphalt emulsion to contain radon and other potentially hazardous materials in uranium tailings. Results of these studies indicate that radon flux from uranium tailings can be reduced by greater than 99% by covering the tailings with an asphalt emulsion that is poured on or sprayed on (3.0 to 7.0 mm thick), or mixed with some of the tailings and compacted to form an admixture seal (2.5 to 15.2 cm) containing 18 wt % residual asphalt.

  4. Investigation of Asphalt Mixture Creep Behavior Using Thin Beam Specimens

    SciTech Connect

    Zofka, Adam; Marasteanu, Mihai; Turos, Mugur

    2008-02-15

    The asphalt pavement layer consists of two or more lifts of compacted asphalt mixture; the top of the layer is also exposed to aging, a factor that significantly affects the mixture properties. The current testing specifications use rather thick specimens that cannot be used to investigate the gradual change in properties with pavement depth. This paper investigates the feasibility of using the 3-point bending test with thin asphalt mixture beams (127x12.7x6.35 mm) to determine the low-temperature creep compliance of the mixtures. Several theoretical and semi-empirical models, from the theory of composites, are reviewed and evaluated using numerical and experimental data. Preliminary results show that this method can be used for low-temperature mixture characterization but several crucial factors need further inspection and interpretation.

  5. Use of recycled chunk rubber asphalt concrete (CRAC) on low volume roads and use of recycled crumb rubber modifier in asphalt pavements. Final report, June 1993-June 1995

    SciTech Connect

    Hossain, M.; Funk, L.P.; Sadeq, M.A.; Marucci, G.

    1995-06-01

    The major objective of this project was to formulate a Chunk Rubber Asphalt Concrete (CRAC) mix for use on low volume roads. CRAC is a rubber modified asphalt concrete product produced by the `dry process` where rubber chunks of 1/2 inch size are used as aggregate in a cold mix with a type C fly ash. The second objective of this project was to develop guidelines concerning the use of rubber modified asphalt concrete hot mix to include: (1) Design methods for use of asphalt-rubber mix for new construction and overlay, (2) Mix design method for asphalt-rubber, and (3) Test method for determining the amount of rubber in an asphalt-rubber concrete for quality control purposes.

  6. Final environmental and regulatory assessment of using asphalt as a sealant in mine shafts

    SciTech Connect

    Not Available

    1987-01-01

    This report discusses the properties of asphalt, the current regulatory status governing asphalt and future regulatory implications which may be pertinent in using asphalt as a waterproof shaft sealant. An understanding of the inherent organic composition of asphalt, an increase in the number of health and environmental research publications conducted on asphalt and an examination of the apparent trend of regulatory agencies toward more stringent environmental regulation governing the use of organic materials suggests asphalt could become regulated at a future time. This would only occur, however, if asphalt was found to conform to the present regulatory definitions of pollutants, contaminants or hazardous substances or if asphalt was included on a regulated substance list. In this regard, the study points out that asphalt contains very low levels of hazardous poly-nuclear aromatics (PNA's). These levels are significantly lower than the levels present in coal tars, a substance known to contain high levels of hazardous PNA's. Asphalt, however, has the inherent potential of producing higher concentrations of PNA's if the adverse condition of cracking should occur during the refinery production stage or on-site preparation of the asphalt. Also, unless existing control technology is applied, emission levels of sulfur dioxide, carbon monoxide, particulates and volatile organic carbons from the on-site preparation facilities could approach the permissible health standard levels of EPA. The study indicates, however, that available literature is limited on these issues.

  7. Automated titration method for use on blended asphalts

    DOEpatents

    Pauli, Adam T.; Robertson, Raymond E.; Branthaver, Jan F.; Schabron, John F.

    2012-08-07

    A system for determining parameters and compatibility of a substance such as an asphalt or other petroleum substance uses titration to highly accurately determine one or more flocculation occurrences and is especially applicable to the determination or use of Heithaus parameters and optimal mixing of various asphalt stocks. In a preferred embodiment, automated titration in an oxygen gas exclusive system and further using spectrophotometric analysis (2-8) of solution turbidity is presented. A reversible titration technique enabling in-situ titration measurement of various solution concentrations is also presented.

  8. Asphalt roofing industry Fourier transform infrared spectroscopy modified bitumen

    SciTech Connect

    1999-07-01

    A Request for Emissions Testing at Four Asphalt Roofing and Processing Facilities was submitted by the US EPA Emission Standards Division (ESD), Minerals and Inorganic Chemicals Group (MICG) to the Emission Measurement Center (EMC). The Emission Measurement Center directed Midwest Research Institute (MRI) to conduct emissions testing at asphalt roofing plants. This report presents results of MRI`s FTIR and Method 25A testing conducted at US Intec in Port Arthur, Texas. The field measurements were performed in September 1997 under several test conditions for both controlled and uncontrolled emissions.

  9. An investigation of waste foundry sand in asphalt concrete mixtures.

    PubMed

    Bakis, Recep; Koyuncu, Hakan; Demirbas, Ayhan

    2006-06-01

    A laboratory study regarding the reuse of waste foundry sand in asphalt concrete production by replacing a certain portion of aggregate with WFS was undertaken. The results showed that replacement of 10% aggregates with waste foundry sand was found to be the most suitable for asphalt concrete mixtures. Furthermore, the chemical and physical properties of waste foundry sand were analysed in the laboratory to determine the potential effect on the environment. The results indicated that the investigated waste foundry sand did not significantly affect the environment around the deposition PMID:16784170

  10. Asphaltic concrete overlays of rigid and flexible pavements

    NASA Astrophysics Data System (ADS)

    Kinchen, R. W.; Temple, W. H.

    1980-10-01

    The development of a mechanistic approach to overlay thickness selection is described. The procedure utilizes a deflection analysis to determine pavement rehabilitation needs. Design guides for selecting the overlay thickness are presented. Tolerable deflection-traffic load relationships and the deflection attenuation properties of asphaltic concrete were developed, representing the subgrade support conditions and properties of materials used in Louisiana. All deflection measurements on asphaltic concrete were corrected for the effect of temperature. Deflection measurements taken before and after overlay were also adjusted to minimize the effects of seasonal subgrade moisture variation.

  11. Energy conservation through recycling of factory asphalt roofing waste

    SciTech Connect

    Shepherd, P.B.; Powers, T.J. . Manville Technical Center); Hardy, J.; Maloof, R.; Patenaude, C.; Zilfi, J. )

    1989-12-31

    Prior DOE laboratory research showed that it was possible to recover the energy resource represented in factory shingle waste. This waste could be processed and recycled into the asphalt composition used to make new shingles. This bench-scale research concluded that factory experiments were all that were needed to provide a basis for commercial implementation. The project reported here completed that full scale research. Factory fiber glass shingle waste was processed to a form suitable for recycling. The processed waste was then mixed into the asphalt used to make new shingles. Process parameters and shingle quality were measured to provide a basis for commercial implementation.

  12. Numerical simulation on the thermal response of heat-conducting asphalt pavements

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Wu, Shaopeng; Chen, Mingyu; Zhang, Yuan

    2010-05-01

    Using asphalt pavements as a solar collector is a subject of current interest all over the world because the sun provides a cheap and abundant source of clean and renewable energy, which can be captured by black asphalt pavements. A heat-conducting device is designed to absorb energy from the sun. In order to validate what parameters are critical in the asphalt collector, a finite element model is developed to predict the thermal response of the heat-conducting device compared to the conventional asphalt mixture. Some factors that may affect the asphalt pavement collector are considered, including the coefficient of heat conductivity of the asphalt pavement, the distance between pipes with the medium, water, and the pipe's diameter. Ultimately, the finite element model can provide pavement engineers with an efficient computational tool that can be a guide to the conductive asphalt solar collector's experiment in the laboratory.

  13. Background of superpave asphalt mixture design and analysis. National asphalt training center demonstration project 101. Final report, December 1992-November 1994

    SciTech Connect

    McGennis, R.B.; Anderson, R.M.; Kennedy, T.W.; Solaimanian, M.

    1995-02-01

    The manual represents the first formal training document that embodies the complete series of SUPERPAVE asphalt mixture design and analysis test equipment and procedures. These tests and procedures represent the results of the SHRP 5-year research effort to investigate and improve asphalt cement technology. This manual was developed under the FHWA`s National Asphalt Training Center. Students attending the center utilize this manual to obtain a better understanding of the underlying theory behind asphalt mixture design and analysis, as well as how to perform each of the new procedures.

  14. Novel Binders and Methods for Agglomeration of Ore

    SciTech Connect

    S. K. Kawatra; T. C. Eisele; J. A. Gurtler; K. Lewandowski

    2005-09-30

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily at a reasonable cost. A primary example of this is copper heap leaching, where there are no binders currently encountered in this acidic environment process. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching. The active involvement of our industrial partners will help to ensure rapid commercialization of any agglomeration technologies developed by this project.

  15. Novel Binders and Methods for Agglomeration of Ore

    SciTech Connect

    S. K. Kawatra; T. C. Eisele; J. A. Gurtler

    2004-03-31

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. A primary example of this is copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process. As a result, operators of acidic heap-leach facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of other agglomeration applications, particularly advanced primary ironmaking.

  16. Novel Binders and Methods for Agglomeration of Ore

    SciTech Connect

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-03-31

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily at a reasonable cost. A primary example of this is copper heap leaching, where there are no binders currently encountered in this acidic environment process. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching. The active involvement of our industrial partners will help to ensure rapid commercialization of any agglomeration technologies developed by this project.

  17. Performance analysis of flexible DSSC with binder addition

    NASA Astrophysics Data System (ADS)

    Muliani, Lia; Hidayat, Jojo; Anggraini, Putri Nur

    2016-04-01

    Flexible DSSC is one of modification of DSSC based on its substrate. Operating at low temperature, flexible DSSC requires a binder to improve particles interconnection. This research was done to compare the morphology and performance of flexible DSSC that was produced with binder-added and binder-free. TiO2 powder, butanol, and HCl were mixed for preparation of TiO2 paste. Small amount of titanium isopropoxide as binder was added into the mixture. TiO2 paste was deposited on ITO-PET plastic substrate with area of 1x1 cm2 by doctor blade method. Furthermore, SEM, XRD, and BET characterization were done to analyze morphology and surface area of the TiO2 photoelectrode microstructures. Dyed TiO2 photoelectrode and platinum counter electrode were assembled and injected by electrolyte. In the last process, flexible DSSCs were illuminated by sun simulator to do J-V measurement. As a result, flexible DSSC containing binder showed higher performance with photoconversion efficiency of 0.31%.

  18. FE Simulation of Effective Distributed Binder Force Trajectories on Stamping Performance

    NASA Astrophysics Data System (ADS)

    Yagami, Tetsuya; Manabe, Ken-ichi

    2004-06-01

    The effect of variable distributed binder force control on the stamping performance of non-axisymmetric part was evaluated using commercial finite element (FE) code LS-DYNA. Distributed binder force control was performed in FE simulation of square-cup deep-drawing process by introducing a segment binder with 108 segments. To obtain effective binder force trajectories for the binder segments, a binder force process control algorithm based on fuzzy inference method was presented and applied in the simulation. From the implementation of the simulation for several material models with linear hardening plasticity, the possibility of improvement in forming height was demonstrated.

  19. Towards identification of traditional European and indigenous Australian paint binders using pyrolysis gas chromatography mass spectrometry.

    PubMed

    Reeves, Tiffany; Popelka-Filcoff, Rachel S; Lenehan, Claire E

    2013-11-25

    We report a pyrolysis GC-MS method capable of analysing Indigenous Australian and European binders typically used in the manufacture of culturally important painted works. Eleven different traditional European binders and ten different Indigenous Australian binders were examined. The method allows discrimination between highly complex and impure lipid, resin, polysaccharide, wax, and protein-based binders. Each was found to have characteristic pyrolysis products that were unique to the binder material, demonstrating the potential for differentiation of these binders on Australian Aboriginal artworks towards identification and conservation of cultural heritage.

  20. Advancements in Binder Systems for Solid Freeform Fabrication

    NASA Technical Reports Server (NTRS)

    Cooper, Ken; Munafo, Paul (Technical Monitor)

    2002-01-01

    Paper will present recent developments in advanced material binder systems for solid freeform fabrication (SFF) technologies. The advantage of SFF is the capability to custom fabricate complex geometries directly from computer aided design data in layer- by-layer fashion, eliminated the need for traditional fixturing and tooling. Binders allow for the low temperature processing of 'green' structural materials, either metal, ceramic or composite, in traditional rapid prototyping machines. The greatest obstacle comes when green parts must then go through a sintering or burnout process to remove the binders and fully densify the parent material, without damaging or distorting the original part geometry. Critical issues and up-to-date assessments will be delivered on various material systems.

  1. Elastomeric binders for electrodes. [in secondary lithium cells

    NASA Technical Reports Server (NTRS)

    Yen, S. P. S.; Shen, D. H.; Somoano, R. B.

    1983-01-01

    The poor mechanical integrity of the cathode represents an important problem which affects the performance of ambient temperature secondary lithium cells. Repeated charge of a TiS2 cathode may give rise to stresses which disturb the electrode structure and can contribute to capacity loss. An investigation indicates that the use of an inelastic binder material, such as Teflon, aggravates the problem, and can lead to electrode disruption and poor TiS2 particle-particle contact. The feasibility of a use of elastomers as TiS2 binder materials has, therefore, been explored. It was found that elastomeric binders provide an effective approach for simplifying rechargeable cathode fabrication. A pronounced improvement in the mechanical integrity of the cathode structure contributes to a prolonged cycle life.

  2. BINDER MODIFICATION AND DEVELOPMENT FOR BRIQUETTING STEEL MILL RESIDUES

    SciTech Connect

    Edwin S. Olson

    1998-07-01

    Alternatives to the molasses-ordinary portland cement (OPC) binder as a binder for steel mill residues were extensively investigated. A large number of binder modifications were tested using a hand pelleting apparatus to identify effective compositions. The more effective compositions were evaluated in a series of three briquetting matrices using the Komarek press. Evaluations consisted of drop tests, compression tests of given and cured pellets, and tumble tests of cured pellets. Pyrolysis odor tests were performed to determine the effects of certain compositions on the disagreeable wet campfire odor produced during heating of the molasses--OPC briquettes. Several scanning electron microscope (SEM) morphology studies were conducted to examine the nature of structures formed during pelleting or briquetting.

  3. In silico design of smart binders to anthrax PA

    NASA Astrophysics Data System (ADS)

    Sellers, Michael; Hurley, Margaret M.

    2012-06-01

    The development of smart peptide binders requires an understanding of the fundamental mechanisms of recognition which has remained an elusive grail of the research community for decades. Recent advances in automated discovery and synthetic library science provide a wealth of information to probe fundamental details of binding and facilitate the development of improved models for a priori prediction of affinity and specificity. Here we present the modeling portion of an iterative experimental/computational study to produce high affinity peptide binders to the Protective Antigen (PA) of Bacillus anthracis. The result is a general usage, HPC-oriented, python-based toolkit based upon powerful third-party freeware, which is designed to provide a better understanding of peptide-protein interactions and ultimately predict and measure new smart peptide binder candidates. We present an improved simulation protocol with flexible peptide docking to the Anthrax Protective Antigen, reported within the context of experimental data presented in a companion work.

  4. An Update on Phosphate Binders: A Dietitian's Perspective.

    PubMed

    Gutekunst, Lisa

    2016-07-01

    Control of serum phosphorus (PO4) has been long recognized as a goal in the nutritional and medical management of the patients with chronic kidney disease. Phosphate-binding compounds were introduced in the 1970s for the treatment of hyperphosphatemia in patients on dialysis after it was observed that oral administration of aluminum hydroxide as an antacid also reduced serum PO4 levels. Forty years later, aluminum is very seldom used as a phosphate binder as many other safer compounds are now available. This article is a comprehensive review, geared to the renal dietitian, of the most common binder categories. It will discuss pharmacokinetics, side effects, initial and optimal doses, phosphate affinity, and controversies of use. It will also review two novel approaches to serum PO4 management in chronic kidney disease patients receiving dialysis and provide a new calculation by which binders can be compared. PMID:26920090

  5. Improvements in Fabrication of Sand/Binder Cores for Casting

    NASA Technical Reports Server (NTRS)

    Bakhitiyarov, Sayavur I.; Overfelt, Ruel A.; Adanur, Sabit

    2005-01-01

    Three improvements have been devised for the cold-box process, which is a special molding process used to make sand/binder cores for casting hollow metal parts. These improvements are: The use of fiber-reinforced composite binder materials (in contradistinction to the non-fiber-reinforced binders used heretofore), The substitution of a directed-vortex core-blowing subprocess for a prior core-blowing process that involved a movable gassing plate, and The use of filters made from filtration-grade fabrics to prevent clogging of vents. For reasons that exceed the scope of this article, most foundries have adopted the cold-box process for making cores for casting metals. However, this process is not widely known outside the metal-casting industry; therefore, a description of pertinent aspects of the cold-box process is prerequisite to a meaningful description of the aforementioned improvements. In the cold-box process as practiced heretofore, sand is first mixed with a phenolic resin (considered to be part 1 of a three-part binder) and an isocyanate resin (part 2 of the binder). Then by use of compressed air, the mixture is blown into a core box, which is a mold for forming the core. Next, an amine gas (part 3 of the binder) that acts as a catalyst for polymerization of parts 1 and 2 is blown through the core box. Alternatively, a liquid amine that vaporizes during polymerization can be incorporated into the sand/resin mixture. Once polymerization is complete, the amine gas is purged from the core box by use of compressed air. The finished core is then removed from the core box.

  6. The Asphalt Identikit: Old Age and the Driver's License.

    ERIC Educational Resources Information Center

    Eisenhandler, Susan A.

    1990-01-01

    Used a recent study of older adults (N=50) from a small community to explore use of the "asphalt identikit" (possession of a valid driver's license and driving) to maintain non-age-related and hence unstigmatized identity. Found resistance to giving up driving was strong even as self-imposed limits curtailed driving. (Author/TE)

  7. Coal tar-containing asphalt - resource or hazardous waste?

    SciTech Connect

    Andersson-Skold, Y.; Andersson, K.; Lind, B.; Claesson, A.; Larsson, L.; Suer, P.; Jacobson, T.

    2007-09-30

    Coal tar was used in Sweden for the production of asphalt and for the drenching of stabilization gravel until 1973. The tar has high concentrations of polycyclic aromatic hydrocarbons (PAH), some of which may be strongly carcinogenic. Approximately 20 million tonnes of tar-containing asphalt is present in the public roads in Sweden. Used asphalt from rebuilding can be classified as hazardous waste according to the Swedish Waste Act. The cost of treating the material removed as hazardous waste can be very high due to the large amount that has to be treated, and the total environmental benefit is unclear. The transport of used asphalt to landfill or combustion will affect other environmental targets. The present project, based on three case studies of road projects in Sweden, evaluates the consequences of four scenarios for handling the material: reuse, landfill, biological treatment, and incineration. The results show that reuse of the coal tar-containing materials in new road construction is the most favorable alternative in terms of cost, material use, land use, energy consumption, and air emissions.

  8. Assessment of Water Quality of Runoff from Sealed Asphalt Surfaces

    EPA Science Inventory

    This report discusses the results of runoff tests from recently-sealed asphalt surfaces conducted at EPA's Urban Watershed Research Facility (UWRF) in Edison, New Jersey. Both bench-scale panels and full-scale test plots were evaluated. Full-scale tests were performed on an asp...

  9. Asphalt and Wood Shingling. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    Brown, Arthur

    This combination workbook and set of tests contains materials on asphalt and wood shingling that have been designed to be used by those studying to enter the roofing and waterproofing trade. It consists of seven instructional units and seven accompanying objective tests. Covered in the individual units are the following topics: shingling…

  10. Paleomagnetism of paleozoic asphaltic deposits in southern Oklahoma, USA

    NASA Astrophysics Data System (ADS)

    Ellwood, Brooks B.; Crick, Rex E.

    1988-05-01

    Paleomagnetic measurements on asphaltic samples from two formations in southern Oklahoma have been performed. A bioclastic unit from the Boggy Formation, known as the Buckhorn asphalt, exhibited a stable, characteristic remanent moment (RM) after A.F. demagnetization between 5-20 mT. We infer from our data that very fine, possibly authigenic magnetite, like that shown to have a genetic relationship with the migration through rocks of hydrocarbons [Elmore et al., 1987], is the primary RM carrier in these samples. The tilt corrected paleopole for the Buckhorn asphalt (121.9 E; 43.5N; δp=1.3 δm=2.3) falls on the Early Permian Apparent Polar Wander Path for North America of Irving and Irving [1982], using a 30 Ma window (270-280 Ma). Because the Boggy Form-ation, containing the Buckhorn asphalt, was depos-ited during the Late Pennsylvanian (Desmoinesian), we interpret the data to indicate magnetization during minor uplift in the Early Permian of the Arbuckle Mountain region. The RM appears to have been acquired at this time, probably as the result of magnetite production facilitated by the introduction time of sulfate reducing bacteria.

  11. Evaluation of emulsified asphalt for use in Saudi Arabia

    SciTech Connect

    Al-Abdulwahhab, H.I.

    1985-01-01

    Saudi Arabia currently contains 31,000 km (18,600 mi) of paved roads and 42,000 km (25,200 mi) of agricultural roads, with the prospect of more roads to be constructed. The low population (6 million) compared to the large area of the country (2,253,300 kmS, 900,000 miS) coupled with the high cost of crushed aggregate makes maintenance and road building costs very high. Local emulsified-asphalt economics, plants, and uses were investigated in this study. Emulsified asphalt proved to be attractive when used for local road maintenance and road bases and low-volume road construction, especially when used with dune sand and marl. Emulsified asphalts were evaluated for use with dune sand and marl and at two portland cement contents. Three types of emulsified asphalts were used which included locally produced, laboratory prepared, and Chevron USA emulsions. Emulsion treated mixes were tested for tensile strength, Poisson's ratio, resilient modulus, fatigue life, and rutting characteristics. Both diametral and beam fatigue tests were used and tests were conducted at 10, 25, 40, and 55C (50, 77, 104, and 131F). The open-graded mix was tested for fatigue characteristics using beam flexure with a confining membrane.

  12. Electronically conductive polymer binder for lithium-ion battery electrode

    SciTech Connect

    Liu, Gao; Xun, Shidi; Battaglia, Vincent S; Zheng, Honghe

    2014-10-07

    A family of carboxylic acid group containing fluorene/fluorenon copolymers is disclosed as binders of silicon particles in the fabrication of negative electrodes for use with lithium ion batteries. These binders enable the use of silicon as an electrode material as they significantly improve the cycle-ability of silicon by preventing electrode degradation over time. In particular, these polymers, which become conductive on first charge, bind to the silicon particles of the electrode, are flexible so as to better accommodate the expansion and contraction of the electrode during charge/discharge, and being conductive promote the flow battery current.

  13. 40 CFR 427.40 - Applicability; description of the asbestos paper (elastomeric binder) subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asbestos paper (elastomeric binder) subcategory. 427.40 Section 427.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Elastomeric Binder) Subcategory § 427.40 Applicability; description...

  14. 40 CFR 427.40 - Applicability; description of the asbestos paper (elastomeric binder) subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asbestos paper (elastomeric binder) subcategory. 427.40 Section 427.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Elastomeric Binder) Subcategory § 427.40 Applicability; description...

  15. 40 CFR 427.40 - Applicability; description of the asbestos paper (elastomeric binder) subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asbestos paper (elastomeric binder) subcategory. 427.40 Section 427.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Elastomeric Binder) Subcategory § 427.40...

  16. 40 CFR 427.40 - Applicability; description of the asbestos paper (elastomeric binder) subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asbestos paper (elastomeric binder) subcategory. 427.40 Section 427.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Elastomeric Binder) Subcategory § 427.40...

  17. 40 CFR 427.40 - Applicability; description of the asbestos paper (elastomeric binder) subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asbestos paper (elastomeric binder) subcategory. 427.40 Section 427.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Paper (Elastomeric Binder) Subcategory § 427.40...

  18. Policies and procedures: from binders to PCs: a retrospective.

    PubMed

    Shibilski, Jane; Vogt, Paula

    2002-01-01

    This article describes the implementation of an online, document-tracking system for policies and procedures. The process of converting from a "binder system" to an online, paperless system is described in detail. The advantages of real-time computer access to staff are identified as well as the necessary steps needed to move an entire hospital into the future and use emerging technology.

  19. Method for freeforming objects with low-binder slurry

    DOEpatents

    Cesarano, III, Joseph; Calvert, Paul D.

    2002-01-01

    In a rapid prototyping system, a part is formed by depositing a bead of slurry that has a sufficient high concentration of particles to be pseudoplastic and almost no organic binders. After deposition the bead is heated to drive off sufficient liquid to cause the bead to become dilatant.

  20. 47 CFR 51.232 - Binder group management.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 3 2013-10-01 2013-10-01 false Binder group management. 51.232 Section 51.232 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) INTERCONNECTION... loop technology. (b) Any party seeking designation of a technology as a known disturber should file...

  1. 47 CFR 51.232 - Binder group management.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 3 2011-10-01 2011-10-01 false Binder group management. 51.232 Section 51.232 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) INTERCONNECTION... loop technology. (b) Any party seeking designation of a technology as a known disturber should file...

  2. 47 CFR 51.232 - Binder group management.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Binder group management. 51.232 Section 51.232 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) INTERCONNECTION... loop technology. (b) Any party seeking designation of a technology as a known disturber should file...

  3. Characterization and treatment of runoff from highways in the Netherlands paved with impervious and pervious asphalt

    SciTech Connect

    Berbee, R.; Rijs, G.; Brouwer, R. de; Velzen, L. van

    1999-03-01

    This paper presents the results of a study to assess the effects of impervious and pervious (or porous) asphalt on the quality of runoff from highways in the Netherlands. Furthermore, the effects of settling and filtration on the quality of runoff of both types of asphalt have been elaborated. This study has been performed to support decisionmaking on how to deal with polluted runoff from highways in the Netherlands. The results show that runoff from well-maintained pervious asphalt contains a relatively low concentration of pollutants such as heavy metals, mineral oil, polynuclear aromatic hydrocarbons, and suspended solids compared to runoff from impervious asphalt. In runoff from both types of asphalt, copper, lead, and zinc are the prevailing heavy metals. The impression exists that especially the hard shoulders along highways provided with pervious asphalt act as a sink for suspended solids, soil particles, and other pollutants. To maintain its permeability and filter action, the hard shoulders should be regularly cleaned.

  4. SGC tests for influence of material composition on compaction characteristic of asphalt mixtures.

    PubMed

    Chen, Qun; Li, Yuzhi

    2013-01-01

    Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes. PMID:23818830

  5. SGC Tests for Influence of Material Composition on Compaction Characteristic of Asphalt Mixtures

    PubMed Central

    Chen, Qun

    2013-01-01

    Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes. PMID:23818830

  6. 40 CFR 427.30 - Applicability; description of the asbestos paper (starch binder) subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asbestos paper (starch binder) subcategory. 427.30 Section 427.30 Protection of Environment ENVIRONMENTAL... Asbestos Paper (Starch Binder) Subcategory § 427.30 Applicability; description of the asbestos paper (starch binder) subcategory. The provisions of this subpart are applicable to discharges resulting...

  7. 40 CFR 427.30 - Applicability; description of the asbestos paper (starch binder) subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asbestos paper (starch binder) subcategory. 427.30 Section 427.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Asbestos Paper (Starch Binder) Subcategory § 427.30 Applicability; description of the asbestos paper (starch binder) subcategory. The provisions of this subpart are applicable to...

  8. 40 CFR 427.30 - Applicability; description of the asbestos paper (starch binder) subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asbestos paper (starch binder) subcategory. 427.30 Section 427.30 Protection of Environment ENVIRONMENTAL... Asbestos Paper (Starch Binder) Subcategory § 427.30 Applicability; description of the asbestos paper (starch binder) subcategory. The provisions of this subpart are applicable to discharges resulting...

  9. 40 CFR 427.30 - Applicability; description of the asbestos paper (starch binder) subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asbestos paper (starch binder) subcategory. 427.30 Section 427.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Asbestos Paper (Starch Binder) Subcategory § 427.30 Applicability; description of the asbestos paper (starch binder) subcategory. The provisions of this subpart are applicable to...

  10. 40 CFR 427.30 - Applicability; description of the asbestos paper (starch binder) subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asbestos paper (starch binder) subcategory. 427.30 Section 427.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Asbestos Paper (Starch Binder) Subcategory § 427.30 Applicability; description of the asbestos paper (starch binder) subcategory. The provisions of this subpart are applicable to...

  11. Novel Binders and Methods for Agglomeration of Ore

    SciTech Connect

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-09-30

    Heap leaching is one of the methods being used to recover metal from low grade ore deposits. The main problem faced during heap leaching is the migration of fine grained particles through the heap, forming impermeable beds which result in poor solution flow. The poor solution flow leads to less contact between the leach solution and the ore, resulting in low recovery rates. Agglomeration of ore into coarse, porous masses prevents fine particles from migrating and clogging the spaces and channels between the larger ore particles. Currently, there is one facility in the United States which uses agglomeration. This operation agglomerates their ore using leach solution (raffinate), but is still experiencing undesirable metal recovery from the heaps due to agglomerate breakdown. The use of a binder, in addition to the leach solution, during agglomeration would help to produce stronger agglomerates that did not break down during processing. However, there are no known binders that will work satisfactorily in the acidic environment of a heap, at a reasonable cost. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. Increasing copper recovery in heap leaching by the use of binders and agglomeration would result in a significant decrease in the amount of energy consumed. Assuming that 70% of all the leaching heaps would convert to using agglomeration technology, as much as 1.64*10{sup 12} BTU per year would be able to be saved if a 25% increase in copper recovery was experienced, which is equivalent to saving approximately 18% of the energy currently being used in leaching heaps. For every week a leach cycle was decreased, a savings of as much as 1.23*10{sup 11} BTU per week would result. This project has identified several acid-resistant binders and agglomeration procedures. These binders and experimental procedures will be able to be used for use in improving the energy efficiency of

  12. Tertiary nitrogen heterocyclic material to reduce moisture-induced damage in asphalt-aggregate mixtures

    DOEpatents

    Plancher, Henry; Petersen, Joseph C.

    1982-01-01

    Asphalt-aggregate roads crack when subjected to freezing and thawing cycles. Herein, the useful life of asphalts are substantially improved by a minor amount of a moisture damage inhibiting agent selected from compounds having a pyridine moiety, including acid salts of such compounds. A shale oil fraction may serve as the source of the improving agent and may simply be blended with conventional petroleum asphalts.

  13. Tertiary nitrogen heterocyclic material to reduce moisture-induced damage in asphalt-aggregate mixtures

    SciTech Connect

    Petersen, J.C.; Plancher, H.

    1982-04-20

    Asphalt-aggregate roads crack when subjected to freezing and thawing cycles. Herein, the useful life of asphalts are substantially improved by a minor amount of a moisture damage inhibiting agent selected from compounds having a pyridine moiety , including acid salts of such compounds. A shale oil fraction may serve as the source of the improving agent and may simply be blended with conventional petroleum asphalts.

  14. The reinforcement and healing of asphalt mastic mixtures by rejuvenator encapsulation in alginate compartmented fibres

    NASA Astrophysics Data System (ADS)

    Tabaković, A.; Post, W.; Cantero, D.; Copuroglu, O.; Garcia, S. J.; Schlangen, E.

    2016-08-01

    This paper explores the potential use of compartmented alginate fibres as a new method of incorporating rejuvenators into asphalt pavement mixtures. The compartmented fibres are employed to locally distribute the rejuvenator and to overcome the problems associated with spherical capsules and hollow fibres. The work presents proof of concept of the encapsulation process which involved embedding the fibres into the asphalt mastic mixture and the survival rate of fibres in the asphalt mixture. To prove the effectiveness of the alginate as a rejuvenator encapsulating material and to demonstrate its ability survive asphalt production process, the fibres containing the rejuvenator were prepared and subjected to thermogravimetric analysis and uniaxial tensile test. The test results demonstrated that fibres have suitable thermal and mechanical strength to survive the asphalt mixing and compaction process. The CT scan of an asphalt mortar mix containing fibres demonstrated that fibres are present in the mix in their full length, undamaged, providing confirmation that the fibres survived the asphalt production process. In order to investigate the fibres physiological properties and ability to release the rejuvenator into cracks in the asphalt mastic, the environmental scanning electron microscope and optical microscope analysis were employed. To prove its success as an asphalt healing system, compartmented alginate fibres containing rejuvenator were embedded in asphalt mastic mix. The three point bend tests were performed on the asphalt mastic test samples and the degree to which the samples began to self-heal in response was measured and quantified. The research findings indicate that alginate fibres present a promising new approach for the development of self-healing asphalt pavement systems.

  15. Integrated coke, asphalt and jet fuel production process and apparatus

    DOEpatents

    Shang, Jer Y.

    1991-01-01

    A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

  16. Factory performance evaluations of engineering controls for asphalt paving equipment.

    PubMed

    Mead, K R; Mickelsen, R L; Brumagin, T E

    1999-08-01

    This article describes a unique analytical tool to assist the development and implementation of engineering controls for the asphalt paving industry. Through an agreement with the U.S. Department of Transportation, the National Asphalt Pavement Association (NAPA) requested that the National Institute for Occupational Safety and Health (NIOSH) assist U.S. manufacturers of asphalt paving equipment with the development and evaluation of engineering controls. The intended function of the controls was to capture and remove asphalt emissions generated during the paving process. NIOSH engineers developed a protocol to evaluate prototype engineering controls using qualitative smoke and quantitative tracer gas methods. Video recordings documented each prototype's ability to capture theatrical smoke under "managed" indoor conditions. Sulfur hexafluoride (SF6), released as a tracer gas, enabled quantification of the capture efficiency and exhaust flow rate for each prototype. During indoor evaluations, individual prototypes' capture efficiencies averaged from 7 percent to 100 percent. Outdoor evaluations resulted in average capture efficiencies ranging from 81 percent down to 1 percent as wind gusts disrupted the ability of the controls to capture the SF6. The tracer gas testing protocol successfully revealed deficiencies in prototype designs which otherwise may have gone undetected. It also showed that the combination of a good enclosure and higher exhaust ventilation rate provided the highest capture efficiency. Some manufacturers used the stationary evaluation results to compare performances among multiple hood designs. All the manufacturers identified areas where their prototype designs were susceptible to cross-draft interferences. These stationary performance evaluations proved to be a valuable method to identify strengths and weaknesses in individual designs and subsequently optimize those designs prior to expensive analytical field studies. PMID:10462852

  17. Systematic Investigation of Binders for Silicon Anodes: Interactions of Binder with Silicon Particles and Electrolytes and Effects of Binders on Solid Electrolyte Interphase Formation.

    PubMed

    Nguyen, Cao Cuong; Yoon, Taeho; Seo, Daniel M; Guduru, Pradeep; Lucht, Brett L

    2016-05-18

    The effects of different binders, polyvinylidene difluoride (PVdF), poly(acrylic acid) (PAA), sodium carboxymethyl cellulose (CMC), and cross-linked PAA-CMC (c-PAA-CMC), on the cycling performance and solid electrolyte interphase (SEI) formation on silicon nanoparticle electrodes have been investigated. Electrodes composed of Si-PAA, Si-CMC, and Si-PAA-CMC exhibit a specific capacity ≥3000 mAh/g after 20 cycles while Si-PVdF electrodes have a rapid capacity fade to 1000 mAh/g after just 10 cycles. Infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) reveal that PAA and CMC react with the surface of the Si nanoparticles during electrode fabrication. The fresh Si-CMC electrode has a thicker surface coating of SiOx than Si-PAA and Si-PAA-CMC electrodes, due to the formation of thicker SiOx during electrode preparation, which leads to lower cyclability. The carboxylic acid functional groups of the PAA binder are reactive toward the electrolyte, causing the decomposition of LiPF6 and dissolution of SiOx during the electrode wetting process. The PAA and CMC binder surface films are then electrochemically reduced during the first cycle to form a protective layer on Si. This layer effectively suppresses the decomposition of carbonate solvents during cycling resulting in a thin SEI. On the contrary, the Si-PVDF electrode has poor cycling performance and continuous reduction of carbonate solvents is observed resulting in the generation of a thicker SEI. Interestingly, the Lewis basic -CO2Na of CMC was found to scavenge HF in electrolyte. PMID:27135935

  18. Evaluation of energies of interaction correlated with observed stabilities and rheological properties of asphalt-aggregate mixtures of western shale-oil residue as a modifier to petroleum asphalt

    SciTech Connect

    Tauer, J.E.; Ensley, E.K.; Harnsberger, P.M.; Robertson, R.E.

    1993-02-01

    The objective of this study was to perform a preliminary evaluation of improving bonding and aging characteristics using a distillation residue from the Green River Formation (western) shale oil as a modifier to a petroleum asphalt for use as a crack and joint filler material in portland cement concrete and asphaltic pavements. This study was to examine the differences in moisture damage resistance and adhesion properties, as measured by bonding energy, of shale-oil modified asphalts compared with non-modified asphalts. The shale-oil modified asphalts mechanical properties were not expected to match those of the rubberized asphalt. A commercially available rubberized asphalt crack and joint filler material was also tested only for comparison of mechanical properties. Portland cement concrete briquets prepared with an asphalt material sandwiched between two concrete wafers were tested in a stress-relaxation type of experiment to evaluate the relaxation and recovery properties of the sealant materials. Energy of interaction (bonding energy) measurements were performed on asphalt materials with portland cement concrete, two silicate aggregates, and a limestone aggregate to evaluate the compatibility of the asphalt materials with various aggregates. The results show that the shale-oil modified petroleum asphalt improved the relaxation time, percent recovery, and bonding energy compared with the petroleum asphalt.

  19. Electronically conductive polymer binder for lithium-ion battery electrode

    SciTech Connect

    Liu, Gao; Battaglia, Vincent S.; Park, Sang -Jae

    2015-10-06

    A family of carboxylic acid groups containing fluorene/fluorenon copolymers is disclosed as binders of silicon particles in the fabrication of negative electrodes for use with lithium ion batteries. Triethyleneoxide side chains provide improved adhesion to materials such as, graphite, silicon, silicon alloy, tin, tin alloy. These binders enable the use of silicon as an electrode material as they significantly improve the cycle-ability of silicon by preventing electrode degradation over time. In particular, these polymers, which become conductive on first charge, bind to the silicon particles of the electrode, are flexible so as to better accommodate the expansion and contraction of the electrode during charge/discharge, and being conductive promote the flow battery current.

  20. Electronically conductive polymer binder for lithium-ion battery electrode

    SciTech Connect

    Liu, Gao; Xun, Shidi; Battaglia, Vincent S.; Zheng, Honghe; Wu, Mingyan

    2015-07-07

    A family of carboxylic acid groups containing fluorene/fluorenon copolymers is disclosed as binders of silicon particles in the fabrication of negative electrodes for use with lithium ion batteries. Triethyleneoxide side chains provide improved adhesion to materials such as, graphite, silicon, silicon alloy, tin, tin alloy. These binders enable the use of silicon as an electrode material as they significantly improve the cycle-ability of silicon by preventing electrode degradation over time. In particular, these polymers, which become conductive on first charge, bind to the silicon particles of the electrode, are flexible so as to better accommodate the expansion and contraction of the electrode during charge/discharge, and being conductive promote the flow battery current.

  1. Stability of polymer binders in Li-O2 batteries

    SciTech Connect

    Nasybulin, Eduard N.; Xu, Wu; Engelhard, Mark H.; Nie, Zimin; Li, Xiaohong S.; Zhang, Jiguang

    2013-06-24

    A number of polymers with various chemical structures were studied as binders for air electrodes in Li-O2 batteries. The nature of the polymer significantly affects the binding properties in the carbon electrodes thus altering the discharge performance of Li-O2 batteries. Stability of polymers to the aggressive reduced oxygen species generated during discharge was tested by ball milling them with KO2 and Li2O2, respectively. Most of the polymers decomposed under these conditions and mechanisms of the decompositions are proposed for some of the polymers. Polyethylene was found to have excellent stability and is suggested as robust binder for air electrodes in Li-O2 batteries.

  2. Mechanical Activation of Construction Binder Materials by Various Mills

    NASA Astrophysics Data System (ADS)

    Fediuk, R. S.

    2016-04-01

    The paper deals with the mechanical grinding down to the nano powder of construction materials. During mechanical activation a composite binder active molecules cement minerals occur in the destruction of the molecular defects in the areas of packaging and breaking metastable phase decompensation intermolecular forces. The process is accompanied by a change in the kinetics of hardening of portland cement. Mechanical processes during grinding mineral materials cause, along with the increase in their surface energy, increase the Gibbs energy of powders and, respectively, their chemical activity, which also contributes to the high adhesion strength when contacting them with binders. Thus, the set of measures for mechanical activation makes better use of the weight of components filled with cement systems and adjust their properties. At relatively low cost is possible to provide a spectacular and, importantly, easily repeatable results in a production environment.

  3. Characterization of low-purity clays for geopolymer binder formulation

    NASA Astrophysics Data System (ADS)

    Mostafa, Nasser Y.; Mohsen, Q.; El-maghraby, A.

    2014-06-01

    The production of geopolymer binders from low-purity clays was investigated. Three low-purity clays were calcined at 750°C for 4 h. The calcined clays were chemically activated by the alkaline solutions of NaOH and Na2SiO3. The compressive strength was measured as a function of curing time at room temperature and 85°C. The results were compared with those of a pure kaolin sample. An amorphous aluminosilicate polymer was formed in all binders at both processing temperatures. The results show that, the mechanical properties depend on the type and amount of active aluminum silicates in the starting clay material, the impurities, and the processing temperature.

  4. Infiltration of Nanoparticles into Porous Binder Jet Printed Parts

    SciTech Connect

    Elliott, Amelia; AlSalihi, Sarah; Merriman, Abbey L.; Basti, Mufeed M.

    2016-01-01

    The densification of parts that are produced by binder jetting Additive Manufacturing (AM; a.k.a. “3D Printing”) is an essential step in making them mechanically useful. By increasing the packing factor of the powder bed by incorporating nanoparticles into the binder has potential to alleviate the amount of shrinkage needed for full densification of binder jet parts. We present preliminary data on the use of 316L Stainless Steel Nanoparticles (SSN) to densify 316L stainless steel binder jet parts. Aqueous solutions of Diethylene Glycol (DEG) or Ethylene Glycol (EG) were prepared at different DEG/water and EG/water molar ratios; pH of the solutions was adjusted by the use of 0.10 M sodium hydroxide. Nanoparticles were suspended in a resulted solution at a volume percentage of SSN/solution at 0.5%. The suspension was then sonicated for thirty minutes. One milliliter of the suspension was added stepwise to a sintered, printed disk with the dimensions: (d = 10 mm, h = 3 mm) in the presence of a small magnet. The 3D part was then sintered again. Moreover, the increase in the mass of the 3D part was used as indication of the amount of nanoparticles that diffused in the 3D part. This mass percent increase was studied as a function of pH of the suspension and as function DEG/water molar ratio. Unlike EG, data show that change in pH affects the mass percent when the suspension was made with DEG. Finally, optical analysis of the discs’ cross sections revealed trends metallic densities similar to trends in the data for mass increase with changing pH and water molar ratio.

  5. Low-loss binder for hot pressing boron nitride

    DOEpatents

    Maya, Leon

    1991-01-01

    Borazine derivatives used as low-loss binders and precursors for making ceramic boron nitride structures. The derivative forms the same composition as the boron nitride starting material, thereby filling the voids with the same boron nitride material upon forming and hot pressing. The derivatives have a further advantage of being low in carbon thus resulting in less volatile byproduct that can result in bubble formation during pressing.

  6. Infiltration of Nanoparticles into Porous Binder Jet Printed Parts

    DOE PAGES

    Elliott, Amelia; AlSalihi, Sarah; Merriman, Abbey L.; Basti, Mufeed M.

    2016-01-01

    The densification of parts that are produced by binder jetting Additive Manufacturing (AM; a.k.a. “3D Printing”) is an essential step in making them mechanically useful. By increasing the packing factor of the powder bed by incorporating nanoparticles into the binder has potential to alleviate the amount of shrinkage needed for full densification of binder jet parts. We present preliminary data on the use of 316L Stainless Steel Nanoparticles (SSN) to densify 316L stainless steel binder jet parts. Aqueous solutions of Diethylene Glycol (DEG) or Ethylene Glycol (EG) were prepared at different DEG/water and EG/water molar ratios; pH of the solutionsmore » was adjusted by the use of 0.10 M sodium hydroxide. Nanoparticles were suspended in a resulted solution at a volume percentage of SSN/solution at 0.5%. The suspension was then sonicated for thirty minutes. One milliliter of the suspension was added stepwise to a sintered, printed disk with the dimensions: (d = 10 mm, h = 3 mm) in the presence of a small magnet. The 3D part was then sintered again. Moreover, the increase in the mass of the 3D part was used as indication of the amount of nanoparticles that diffused in the 3D part. This mass percent increase was studied as a function of pH of the suspension and as function DEG/water molar ratio. Unlike EG, data show that change in pH affects the mass percent when the suspension was made with DEG. Finally, optical analysis of the discs’ cross sections revealed trends metallic densities similar to trends in the data for mass increase with changing pH and water molar ratio.« less

  7. Physicochemical and binder properties of starch obtained from Cyperus esculentus.

    PubMed

    Manek, Rahul V; Builders, Philip F; Kolling, William M; Emeje, Martins; Kunle, Olobayo O

    2012-06-01

    The purpose of this study was to isolate starch from the tubers of Cyperus esculentus L. and evaluate its physicochemical and binder properties. Extraction of starch using sodium metabisulfite yielded 37 g of starch per 100 g of the tubers. Scanning electron microscopy indicated that Cyperus starch consists of oval to elliptical particles with a smooth surface. Cyperus starch demonstrates a narrow particle size distribution with a mean of 8.25 μm. Cyperus starch conforms well to United States Pharmacopeia standards established for widely used starches like maize and potato. The X-ray powder diffraction pattern and moisture sorption profile of Cyperus starch were comparable to that of maize starch. Cyperus starch had lower swelling power than maize and potato starch, indicative of stronger associative forces within the granules. Carr's index and Hausner ratio indicate that Cyperus starch should have comparable flow properties with respect to maize and potato starch. Cyperus starch was employed as binder for the formulation of metronidazole tablets. Formulations containing 5%, 7.5%, and 10% Cyperus starch were compared with those containing 10% potato starch. At 10% binder concentration, the tablets containing Cyperus starch exhibited better hardness and negligible friability as compared with those with potato starch. Although the binder concentration had a significant effect on the disintegration time of the tablets, it did not seem to affect the dissolution profile. These results indicate that Cyperus starch provides excellent binding properties without compromising drug release characteristics and should be explored in pharmaceutical formulations. PMID:22350737

  8. Flexible binder free functionalized carbon nanotube electrodes for ultracapacitor

    NASA Astrophysics Data System (ADS)

    Bhat, Badekai Ramachandra; Aravinda, L. S.; Bhat, K. Udaya

    2014-03-01

    The Flexible supercapacitor electrode material was prepared by simple spray coating technique. This will provide a greener alternative for the fabrication of binder free composite electrode for supercapacitor applications. A symmetric double layer super capacitor stack was fabricated by using flexible electrodes. The investigation of the capacitance property of the fabricated super capacitor stack was investigated using cyclic voltammetry, chronopotentiometry and electrical impedance spectroscopy studies. The flexible electrode material shows a specific capacitance of 50 Fg-1 with good cyclibility.

  9. Multifunctional SA-PProDOT Binder for Lithium Ion Batteries.

    PubMed

    Ling, Min; Qiu, Jingxia; Li, Sheng; Yan, Cheng; Kiefel, Milton J; Liu, Gao; Zhang, Shanqing

    2015-07-01

    An environmentally benign, highly conductive, and mechanically strong binder system can overcome the dilemma of low conductivity and insufficient mechanical stability of the electrodes to achieve high performance lithium ion batteries (LIBs) at a low cost and in a sustainable way. In this work, the naturally occurring binder sodium alginate (SA) is functionalized with 3,4-propylenedioxythiophene-2,5-dicarboxylic acid (ProDOT) via a one-step esterification reaction in a cyclohexane/dodecyl benzenesulfonic acid (DBSA)/water microemulsion system, resulting in a multifunctional polymer binder, that is, SA-PProDOT. With the synergetic effects of the functional groups (e.g., carboxyl, hydroxyl, and ester groups), the resultant SA-PProDOT polymer not only maintains the outstanding binding capabilities of sodium alginate but also enhances the mechanical integrity and lithium ion diffusion coefficient in the LiFePO4 (LFP) electrode during the operation of the batteries. Because of the conjugated network of the PProDOT and the lithium doping under the battery environment, the SA-PProDOT becomes conductive and matches the conductivity needed for LiFePO4 LIBs. Without the need of conductive additives such as carbon black, the resultant batteries have achieved the theoretical specific capacity of LiFePO4 cathode (ca. 170 mAh/g) at C/10 and ca. 120 mAh/g at 1C for more than 400 cycles. PMID:26061529

  10. Biochemical properties and binding parameters of the pancreatic estradiol binder.

    PubMed

    Drury, R E; Sandberg, A A

    1987-01-01

    Because the estradiol binder is distributed throughout subcellular fractions from homogenates of the pancreas, an acetone powder was used in extracting soluble components from the entire tissue. The estradiol binder, obtained from the acetone powder of a bovine pancreas, was pH dependent, denatured by heat, inhibited by CuSO4 and reversibly denatured by urea. Binding was enhanced by Mg+2, a common enzymatic cofactor. Its molecular weight was greater than 66,000 D, the molecular weight of bovine serum albumin. An 11-fold purification resulted in a protein preparation that showed a saturating binding curve in equilibrium dialysis. Klotz has severely criticized, if not discredited, the hypothesis that a binding curve is typically due to two classical binding sites and is resolvable into two straight lines. We, therefore, determined the parameters of the binding curve by a computer analysis based on Wilkinson's algebraic method and on McLaren's proposal of surface relationships in enzymatic reactions. The inference from McLaren (namely, binding sites of a single affinity located on the surface of the macromolecular binder), offered a simpler explanation for curvature in Scatchard plots than the two affinity site or the varying affinity hypotheses. The analysis was also applied to other examples from the literature. PMID:3118355

  11. Fabrication of porous silicon nitride ceramics using binder jetting technology

    NASA Astrophysics Data System (ADS)

    Rabinskiy, L.; Ripetsky, A.; Sitnikov, S.; Solyaev, Y.; Kahramanov, R.

    2016-07-01

    This paper presents the results of the binder jetting technology application for the processing of the Si3N4-based ceramics. The difference of the developed technology from analogues used for additive manufacturing of silicon nitride ceramics is a method of the separate deposition of the mineral powder and binder without direct injection of suspensions/slurries. It is assumed that such approach allows reducing the technology complexity and simplifying the process of the feedstock preparation, including the simplification of the composite materials production. The binders based on methyl ester of acrylic acid with polyurethane and modified starch were studied. At this stage of the investigations, the technology of green body's fabrication is implemented using a standard HP cartridge mounted on the robotic arm. For the coordinated operation of the cartridge and robot the specially developed software was used. Obtained green bodies of silicon powder were used to produce the ceramic samples via reaction sintering. The results of study of ceramics samples microstructure and composition are presented. Sintered ceramics are characterized by fibrous α-Si3N4 structure and porosity up to 70%.

  12. Damage detection and artificial healing of asphalt concrete after trafficking with a load simulator

    NASA Astrophysics Data System (ADS)

    Bueno, M.; Arraigada, M.; Partl, M. N.

    2016-08-01

    Artificial healing of asphalt concrete by induction heating requires the addition of electrically conductive and/or magnetic materials into the asphalt mixture. Hence, bitumen can be heated up by an alternating electromagnetic field, decreasing therefore its viscosity and allowing it to flow for closing cracks and recover bonding among the mineral aggregates.

  13. Acute effects and exposure to organic compounds in road maintenance workers exposed to asphalt

    SciTech Connect

    Norseth, T.; Waage, J.; Dale, I. )

    1991-01-01

    Subjective symptoms and exposure to organic compounds were recorded in road repair and construction workers. Abnormal fatigue, reduced appetite, laryngeal/pharyngeal irritation, and eye irritation were recorded more often in such workers handling asphalt than in a corresponding reference group without asphalt exposure. Mean daily exposure to volatile compounds was only occasionally above 1 ppm. Mean exposure to asphalt fume was 0.358 mg/m3. There was no correlation between symptoms and total amount of volatile compounds, but a significant positive correlation was demonstrated between symptoms and some substances. The highest correlation was found for 1, 2, 4 trimethyl benzene. Symptoms increased with increasing asphalt temperature and with increasing concentrations of asphalt fumes. Amine addition did not increase the sum of symptoms, but soft asphalt seems to result in fewer symptoms than the harder types. Symptoms were not related to external factors like weather, traffic density, or specific working operations. As preventive measures, asphalt temperature should be kept below 150 degrees C, fume concentrations below 0.40 mg/m3, and if possible, the use of harder asphalt types which also require high temperatures should be avoided.

  14. Remedial investigation/feasibility study analysis asphalt storage area, Elmendorf AFB, Alaska. Master's thesis

    SciTech Connect

    Miller, N.S.

    1993-01-01

    This report is focused on an abandoned material storage area located on Elmendorf Air Force Base (EAFB), Alaska. The site is located approximately 2000 feet from the east end of the east/west runway and includes approximately 25 acres. The site was used for asphalt storage and preparation activities during the 1940s and 1950s. Approximately 4,500 drums of asphalt and 29 drums of unknown materials have been abandoned at the site. The drums are located in 32 areas throughout the 25-acre site. Following several decades of exposure to the elements, many of the drums have corroded and leaked to the ground surface. Several acres of soil are inundated with liquid asphalt that has leaked from the drums. Depths of the asphalt range from 6 to 10 inches in areas where surface anomalies have created depressions, and thus a collection point for the asphalt. A 14-x 18-x 4 foot wood frame pit used to support previous asphalt operations is located at the north end of the site. The pit contains approximately 2300 gallons of asphalt. There are also locations where the soil appears to be contaminated by petroleum products other than asphalt.

  15. 75 FR 12988 - National Emission Standards for Hazardous Air Pollutants for Area Sources: Asphalt Processing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    ... the asphalt processing and asphalt roofing manufacturing area source category (74 FR 63236). Following... specified in Executive Order 13132, Federalism (64 FR 43255, August 10, 1999). This action does not..., Consultation and Coordination with Indian Tribal Governments (65 FR 67249, November 9, 2000). This...

  16. Chemical aspects of incorporating contaminated soil into cold-mix asphalt

    SciTech Connect

    Testa, S.M.

    1994-12-31

    The chemical aspects associated with the incorporation of petroleum hydrocarbons- and metals-affected soil has been extensively studied in regards to pavement properties, leaching behavior, sensitivities to moisture-damage and function group analysis. These studies provide information that can be used to evaluate the stability of these constituents in soil that have been incorporated as an ingredient in asphalt. These studies also indicate that cold-mix asphalt incorporating contaminated soil will be highly stable and perform adequately as an end product. Maximum chemical performance is achieved when the asphalt is comprised of high contents of pyridinic, phenolic and ketone groups, which can be achieved by selectively choosing the source material. If the situation requires special stability or redundancy, small amounts of shale oil and lime can be used as additives. Situations and conditions which favor the presence of inorganic sulfur, monovalent salts and high strength solutions in the asphalt should be avoided since these conditions decrease the chemical stability of the asphalt cement by disruption of the functional group-aggregate bonds and by increasing the overall permeability. However, these conditions are not typically expected in the anticipated uses of asphalt cement to stabilize contaminants in soil using Environmentally Processed Asphalt{trademark} (EPA{trademark}) or Asphaltic Metals Stabilization{trademark} (AMS{trademark}) remedial technologies.

  17. Recycled materials in asphalt pavements. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1995-03-01

    The bibliography contains citations concerning the recycling of asphalt pavement materials for road construction. Citations discuss asphalt concrete mixtures and recycling, recycled materials testing and evaluation, and pavement bases. Engineering and environmental aspects of recycled materials are examined. (Contains a minimum of 78 citations and includes a subject term index and title list.)

  18. Furfural modified asphalt obtained by using a Lewis acid as a catalyst

    SciTech Connect

    Memon, G.M.

    1996-12-31

    Asphalt is solid or semi-solid at room temperature, becomes soft and starts flowing upon heating, and becomes hard and brittle at very low temperatures. States have been facing problems such as cracking, rutting, and asphalt adhesion to aggregates in their asphaltic pavements for years. Many polymer additives have been used in asphalt to reduce these problems, but little work has been done using chemically modified products of asphalt to attempt to solve these serious problems of asphalt pavements. The above mentioned problems decrease the life of the pavements, resulting in an increase of maintenance and/or replacement costs. There are two types of cracking which can occur in asphalt pavement; one related to load, and the other related to thermal stress. The load-related cracking is known as fatigue cracking and is defined as fracture under repeated or cyclic stress having a maximum value of less than the tensile strength of the material. The thermal cracking occurs due to pavement shrinkage at low temperature causing the shrinkage stresses to exceed the tensile strength. FHWA researchers have found furfural to be a suitable candidate for functional group modification of asphalt. The modified product shows improved performance as well as improved rheological properties.

  19. Airborne Exposures to Polycyclic Aromatic Compounds Among Workers in Asphalt Roofing Manufacturing Facilities.

    PubMed

    Trumbore, David C; Osborn, Linda V; Johnson, Kathleen A; Fayerweather, William E

    2015-01-01

    We studied exposure of 151 workers to polycyclic aromatic compounds and asphalt emissions during the manufacturing of asphalt roofing products-including 64 workers from 10 asphalt plants producing oxidized, straight-run, cutback, and wax- or polymer-modified asphalts, and 87 workers from 11 roofing plants producing asphalt shingles and granulated roll roofing. The facilities were located throughout the United States and used asphalt from many refiners and crude oils. This article helps fill a gap in exposure data for asphalt roofing manufacturing workers by using a fluorescence technique that targets biologically active 4-6 ring polycyclic aromatic compounds and is strongly correlated with carcinogenic activity in animal studies. Worker exposures to polycyclic aromatic compounds were compared between manufacturing plants, at different temperatures and using different raw materials, and to important external benchmarks. High levels of fine limestone particulate in the plant air during roofing manufacturing increased polycyclic aromatic compound exposure, resulting in the hypothesis that the particulate brought adsorbed polycyclic aromatic compounds to the worker breathing zone. Elevated asphalt temperatures increased exposures during the pouring of asphalt. Co-exposures in these workplaces which act as confounders for both the measurement of total organic matter and fluorescence were detected and their influence discussed. Exposures to polycyclic aromatic compounds in asphalt roofing manufacturing facilities were lower than or similar to those reported in hot-mix paving application studies, and much below those reported in studies of hot application of built-up roofing asphalt. These relatively low exposures in manufacturing are primarily attributed to air emission controls in the facilities, and the relatively moderate temperatures, compared to built-up roofing, used in these facilities for oxidized asphalt. The exposure to polycyclic aromatic compounds was a very

  20. Safety of new phosphate binders for chronic renal failure.

    PubMed

    Loghman-Adham, Mahmoud

    2003-01-01

    Phosphate (Pi) retention is a common problem in patients with chronic kidney disease, particularly in those who have reached end-stage renal disease (ESRD). In addition to causing secondary hyperparathyroidism and renal osteodystrophy, recent evidence suggests that, in ESRD patients, high serum phosphorus concentration and increased calcium and phosphorous (Ca x P) product are associated with vascular and cardiac calcifications and increased mortality. Dietary phosphorus restriction and Pi removal by dialysis are not sufficient to restore Pi homeostasis. Reduction of intestinal Pi absorption with the use of Pi binders is currently the primary treatment for Pi retention in patients with ESRD. The use of large doses of calcium-containing Pi binders along with calcitriol administration may contribute to over-suppression of parathyroid hormone secretion and adynamic bone disease as well as to a high incidence of vascular calcifications. When used in patients with impaired renal function, aluminium salts were found to accumulate in bone and other tissues, resulting in osteomalacia and encephalopathy.Sevelamer, an aluminium- and calcium-free Pi binder can reduce serum phosphorus concentration and is associated with a significantly lower incidence of hypercalcaemia, while maintaining the ability to suppress parathyroid hormone production. An additional benefit of sevelamer is its ability to lower low density lipoprotein-cholesterol and total cholesterol levels. Sevelamer attenuates the progression of vascular calcifications in haemodialysis patients, which may lead to lower mortality. The use of sevelamer in non-dialysed patients might aggravate metabolic acidosis, common in these patients. Several other calcium-free Pi binders are in development. Lanthanum carbonate has shown significant promise in clinical trials in ESRD patients. Magnesium salts do not offer a significant advantage over currently available Pi binders. Their use is restricted to patients receiving

  1. Characterization of asphalt cements modified with crumbed rubber from discarded tires. Final report

    SciTech Connect

    Daly, W.H.; Negulescu, I.I.

    1994-11-01

    The potential legislative requirement for incorporation of scrap rubber into asphalt blends mandated a thorough evaluation of the influence of scrap rubber additives on the physical properties and aging characteristics of rubber/asphalt blends. Blends with up to 20 percent ground vulcanized rubber (both crumb and 200 mesh powder particles) from recycled tires were prepared with asphalt cements of various grades (AC5 - AC30) and evaluated using DMA. Blends produced from powdered rubber particles exhibited Newtonian behavior at high temperatures; similar behavior was not observed with crumb rubber blends. The mechanical properties of asphalt-rubber blends depend upon the concentration of rubber additives, the particle dimensions, and the chemical composition of the asphalt.

  2. Beneficial uses of recycled asphalt-stabilized products as landfill cover and capping systems

    SciTech Connect

    Camougis, G.

    1996-12-31

    The American Reclamation Corporation (AMREC{reg_sign}) has played a major role in the development of new programs for the recycling of discarded materials from construction, demolition, remediation and manufacturing operations. Excavated petroleum-contaminated soils (oily soils), asphalt paving, concrete rubble, and discarded asphalt roofing shingles have been processed and recycled into beneficially useful construction products. AMREC uses a cold-mix, asphalt-emulsion technology to process many of the recyclables received at its recycling facility in Charlton, MA. Recyclable materials are processed and blended to produce recycled, asphalt-stabilized products. In addition, recycled, asphalt-stabilized products are being investigated and tested for other beneficial uses. This includes their uses as capping materials and as containment materials.

  3. Crumb rubber modified asphalt concrete in Oregon. Summary report. Report for 1985-94

    SciTech Connect

    Hunt, E.; Peters, W.

    1995-07-01

    Over the last nine years, the Oregon Department of Transportation (ODOT) has constructed 13 projects using crumb rubber modifiers (CRM) in asphalt concrete pavements using both the wet and dry process. State and federal legislation may require the use of recycled rubber in asphalt concrete, therefore, the Oregon Department of Transportation is interested in determining the most cost -effective crumb rubber modified asphalt concrete. The report includes a literature review on the use of crumb rubber modifiers in asphalt concrete pavement; a review on non-ODOT CRM paving projects constructed by Oregon counties and cities; and the Washington Department of Transportation. In additon, the report summarizes the data collected on all CRM hot mix asphalt concrete pavement projects constructed by ODOT. The ODOT information includes background constitution, cost, and performance data for each of the test and control sections. Finally, the future activities of the project are reviewed.

  4. Why is the electroanalytical performance of carbon paste electrodes involving an ionic liquid binder higher than paraffinic binders? A simulation investigation.

    PubMed

    Ghatee, M H; Namvar, S; Zolghadr, A R; Moosavi, F

    2015-10-14

    Recently, carbon paste electrodes (CPE) fabricated using an ionic liquid (IL) binder have shown enhanced electroanalytical performance over conventional paraffinic binders. Molecular dynamics (MD) simulations of graphite mixed with ionic liquid and with paraffin binder can unravel the potential atomistic factors responsible for such enhancement. Based on an experimentally optimized binder/graphite mass ratio, which has been reported to be crucial for such a performance, comprehensive simulations (at 323 K) are performed with the ensembles involving an ionic liquid binder (1-butyl-3-methylimidazolium hexafluorophosphate, [C4mim]PF6) and a paraffin binder (n-C20H42) mixed with graphite comprising large-size hexagonal-shaped double graphene plates. Structural analysis indicates both binders form only a monolayer on the graphite surface, covering the surface locally by IL but all-encompassing by paraffin. With charged and uncharged graphite, the IL monolayer tends to cover mainly the graphite center without approaching the edge planes. On the contrary, a monolayer of the paraffin binder covers uniformly the center, near the center, and the edge planes. Cations and anions of the IL form well-defined two dimensional pentagonal matrixes with characteristic high adsorption energy, almost 2.4 times higher than paraffin adsorption. The cation and anion coordination ability of the IL is responsible for such a local distribution. The simulation of these phenomena under experimental conditions unravels strong two-dimensional coordination properties inherent to the ionic liquid when distributed over the graphite surface. This direct MD simulation comparison of the IL properties with an organic liquid counterpart, made for the first time, can be used to explain the high electroanalytical performance (electron transfer) of CPEs involving an IL binder over paraffin binders.

  5. Evaluation of an eastern shale oil residue as an asphalt additive

    SciTech Connect

    Thomas, K.P.; Harnsberger, P.M.

    1995-09-01

    An evaluation of eastern shale oil (ESO) residue as an asphalt additive to reduce oxidative age hardening and moisture susceptibility was conducted by Western Research Institute (WRI). The ESO residue, have a viscosity of 23.9 Pa{lg_bullet}s at 60{degree}C (140{degree}F), was blended with three different petroleum-derived asphalts, ASD-1, AAK-1, and AAM-1, which are known to be very susceptible to oxidative aging. Rheological and infrared analyses of the unaged and aged asphalts and the blends were then conducted to evaluate oxidative age hardening. In addition, the petroleum-derived asphalts and the blends were coated onto three different aggregates, Lithonia granite (RA), a low-absorption limestone (RD), and a siliceous Gulf Coast gravel (RL), and compacted into briquettes. Successive freeze-thaw cycling was then conducted to evaluate the moisture susceptibility of the prepared briquettes. The rheological analyses of the unaged petroleum-derived asphalts and their respective blends indicate that the samples satisfy the rutting requirement. However, the aging indexes for the rolling thin film oven (RTFO)-aged and RTFO/pressure aging vessel (PAV)-aged samples indicate that the blends are stiffer than the petroleum-derived asphalts. This means that when in service the blends will be more prone to pavement embrittlement and fatigue cracking than the petroleum-derived asphalts. Infrared analyses were also conducted on the three petroleum-derived asphalts and the blends before and after RTFO/PAV aging. In general, upon RTFO/PAV aging, the amounts of carbonyls and sulfoxides in the samples increase, indicating that the addition of the ESO residue does not mitigate the chemical aging (oxidation) of the petroleum-derived asphalts. This information correlates with the rheological data and the aging indexes that were calculated for the petroleum-derived asphalts and the blends.

  6. Hanford Permanent Isolation Barrier Program: Asphalt technology data and status report - FY 1994

    SciTech Connect

    Freeman, H.D.; Romine, R.A.; Zacher, A.H.

    1994-09-01

    The asphalt layer within the Hanford Permanent Isolation Barrier (HPIB) is an important component of the overall design. This layer provides a RCRA equivalent backup to the overlying earthen layers in the unlikely event that these layers are not able to reduce the infiltration rate to less than 0.05 cm/yr. There is only limited amount of information on using asphalt for a moisture infiltration barrier over the long times required by the HPIB. Therefore, a number of activities are under way, as part of the Barrier Development Program, to obtain data on the performance of asphalt as a moisture barrier in a buried environment over a 1000-year period. These activities include (1) determining RCRA equivalency, (2) measurement of physical properties, (3) measurement of aging characteristics, and (4) relationship to ancient asphalt analogs. During FY 1994 progress was made on all of these activities. Studies were conducted both in the laboratory and on the prototype barrier constructed over the 216-B-57 crib in the 200 East Area on the Hanford Site. This report presents results obtained from the asphalt technology tasks during FY 1994. Also included are updates to planned activities for asphalt analogs and monitoring the asphalt test pad near the prototype barrier. Measurements of hydraulic conductivity on the HMAC portion of the prototype barrier show that the asphalt layers easily meet the RCRA standard of 1 {times} 10{sup -7} cm/s. In-place measurements using a new field falling head technique show an average of 3.66 {times} 10{sup -8} cm/s, while cores taken from the north end of the prototype and measured in a laboratory setup averaged 1.29 {times} 10{sup -9} cm/s. Measurements made on the fluid applied asphalt membrane (polymer-modified asphalt) show an extremely low permeability of less than 1 {times} 10{sup -11} cm/s.

  7. Influence of solidification accelerators on structure formation of anhydrite-containing binders

    NASA Astrophysics Data System (ADS)

    Anikanova, L.; Volkova, O.; Kudyakov, A.; Sarkisov, Y.; Tolstov, D.

    2016-01-01

    The article presents results of scientific analysis of chemical additives influence on acid fluoride binder. It was found that the influence of sulfate nature additives on the process of hydration and solidification of the binder is similar to influence of additives on indissoluble anhydrite. Additives with SO42- anion NO- are more efficient. The mentioned additives according to accelerating effect belong to the following succession: K2SO4 > Na2SO4 > FeSO4 > MgSO4. Facilitation of the process of hydration and solidification of the binder, increase in density and durability of the binder (32 MPa) is to the greatest extent achieved with the introduction of 2% sodium sulfate additive of the binder's mass into the composition of the binder along with the ultrasonic treatment of water solution. Directed crystal formation process with healing of porous structure by new growths presented as calcium sulfate dehydrate and hydroglauberite provides positive effect.

  8. Evaluation of the benefits of adding waste fiberglass roofing shingles to Hot-Mix asphalt. Final report

    SciTech Connect

    Abdulshafi, O.; Kedzierski, B.; Fitch, M.G.; Mukhtar, H.

    1997-07-03

    The decreased availability of landfills, growing concern over waste disposal, and rising cost of asphalt cement, resulted in an increased interest in incorporating waste asphalt roofing shingles in the production of asphalt concrete mixes. This project addressed Hot-Mix, surface course asphalt concrete mixes produced with an addition of waste fiberglass asphalt roofing shingles that were obtained from the shingle manufacturing process. A total of twenty-six asphalt concrete mixes were studied. The variables included: aggregate type, shingle producers, level of shingle addition (0, 5, 10, and 15%), and type of shingle size reduction. Properties of the produced asphalt concrete mixes were evaluated based on the results of applicable tests that were performed.

  9. Dermal exposure and urinary 1-hydroxypyrene among asphalt roofing workers

    SciTech Connect

    McClean, M.D.; Rinehart, R.D.; Sapkota, A.; Cavallari, J.M.; Herrick, R.F.

    2007-07-01

    The primary objective of this study was to identify significant determinants of dermal exposure to polycyclic aromatic compounds (PACs) among asphalt roofing workers and use urinary 1-hydroxyprene (1-OHP) measurements to evaluate the effect of dermal exposure on total absorbed dose. The study population included 26 asphalt roofing workers who performed three primary tasks: tearing off old roofs, putting down new roofs, and operating the kettle at ground level. During multiple consecutive work shifts, dermal patch samples were collected from the underside of each worker's wrists and were analyzed for PACs, pyrene, and benzo(a)pyrene (BAP). During the same work week, urine samples were collected at pre-shift, post-shift, and bedtime each day and were analyzed for 1-OHP (205 urine samples). Linear mixed effects models were used to evaluate the dermal measurements for the purpose of identifying important determinants of exposure, and to evaluate urinary 1-OHP measurements for the purpose of identifying important determinants of total absorbed dose. Dermal exposures to PAC, pyrene, and BAP were found to vary significantly by roofing task and by the presence of an old coal tar pitch roof. For each of the three analytes, the adjusted mean dermal exposures associated with tear-off were approximately four times higher than exposures associated with operating the kettle. Exposure to coal tar pitch was associated with a 6-fold increase in PAC exposure, an 8-fold increase in pyrene exposure and a 35-fold increase in BAP exposure. The presence of coal tar pitch was the primary determinant of dermal exposure, particularly for exposure to BAP. However, the task-based differences that were observed while controlling for pitch suggest that exposure to asphalt also contributes to dermal exposures.

  10. Combustion characteristics of blends of lignite and bituminous coal with different binder materials

    SciTech Connect

    Haykiri-Acma, H.; Ersoy-Mericboyu, A.; Kuecuekbayrak, S.

    2000-05-01

    In this study, the combustion characteristics of blends of a Turkish lignite and a Siberian bituminous coal with and without binder materials were investigated. Sunflower shell, sawdust, and molasses were used as binder materials. The combustion curves of the coal and binder material samples and of the blends were obtained using differential thermal analysis (DTA). The differences observed in the DTA curves of the samples are discussed in detail.

  11. Study of the aluminum-chromium phosphate binder based on the slurry (slime) orthophosphoric acid

    SciTech Connect

    Kliment'eva, V.S.; Filimonova, N.I.; Bushmina, V.A.; Vasil'eva, N.F.; Kudinova, A.A.

    1987-03-01

    This article looks at the possibility of using phosphorus slurry wastes which are ordinarily incinerated as a raw material for a refractory binder based on aluminium and chromium phosphates. Thermal gravimetric and differential thermal analysis as well as x-ray diffraction are carried out on various combinations of binder and refractory in order to assess the crystal behavior, adhesive properties, and temperature resistance of the binder-filler composite.

  12. Environmentally-Friendly Geopolymeric Binders Made with Silica

    NASA Astrophysics Data System (ADS)

    Erdogan, S. T.

    2013-12-01

    Portland cement (PC) is the ubiquitous binding material for constructions works. It is a big contributor to global warming and climate change since its production is responsible for 5-10 % of all anthropogenic CO2 emissions. Half of this emission arises from the calcination of calcareous raw materials and half from kiln fuel burning and cement clinker grinding. Recently there have been efforts to develop alternative binders with lower greenhouse gas emissions. One such class of binders is geopolymers, formed by activating natural or waste materials with suitable alkaline or acidic solutions. These binders use natural or industrial waste raw materials with a very low CO2 footprint from grinding of the starting materials, and some from the production of the activating chemicals. The total CO2 emissions from carefully formulated mixtures can be as low as 1/10th - 1/5th of those of PC concrete mixtures with comparable properties. While use of industrial wastes as raw materials is environmentally preferable, the variability of their chemical compositions over time renders their use difficult. Use of natural materials depletes resources but can have more consistent properties and can be more easily accepted. Silica sand is a natural material containing very high amounts of quartz. Silica fume is a very fine waste from silicon metal production that is mostly non-crystalline silica. This study describes the use of sodium hydroxide and sodium silicate solutions to yield mortars with mechanical properties comparable to those of portland cement mortars and with better chemical and thermal durability. Strength gain is slower than with PC mixtures at room temperature but adequate ultimate strength can be achieved with curing at slightly elevated temperatures in less than 24 h. The consistency of the chemical compositions of these materials and their abundance in several large, developing countries makes silica attractive for producing sustainable concretes with reduced carbon

  13. Microstructure of the combustion zone: Thin-binder AP-polymer sandwiches

    NASA Technical Reports Server (NTRS)

    Price, E. W.; Panyam, R. R.; Sigman, R. K.

    1980-01-01

    Experimental results are summarized for systematic quench-burning tests on ammonium perchlorate-HC binder sandwiches with binder thicknesses in the range 10 - 150 microns. Tests included three binders (polysulfide, polybutadiene-acrylonitrile, and hydroxy terminated polybutadiene), and pressures from 1.4 to 14 MPa. In addition, deflagration limits were determined in terms of binder thickness and pressure. Results are discussed in terms of a qualitative theory of sandwich burning consolidated from various sources. Some aspects of the observed results are explained only speculatively.

  14. A new binder for powder injection molding titanium and other reactive metals

    SciTech Connect

    Weil, K. Scott; Nyberg, Eric A.; Simmons, Kevin L.

    2006-06-26

    We have developed a new aromatic-based binder for powder injection molding (PIM) reactive metals, such as titanium, zirconium, niobium, tungsten, and molybdenum. Because of careful selection of the binder constituents, thermal removal is readily accomplished at low temperatures and short-times via vacuum sublimation. In this way the binder can be cleanly extracted from the green part prior to sintering to minimize the amount of residual carbon left in the final component. Rheological measurements indicate that powder loadings in the PIM feedstock as high as 67 vol% could be achieved using the new binder system, while still maintaining low mixing torques and injection molding pressures.

  15. Novel anti-flooding poly(dimethylsiloxane) (PDMS) catalyst binder for microbial fuel cell cathodes

    NASA Astrophysics Data System (ADS)

    Zhang, Fang; Chen, Guang; Hickner, Michael A.; Logan, Bruce E.

    2012-11-01

    Poly(dimethylsiloxane) (PDMS) was investigated as an alternative to Nafion as an air cathode catalyst binder in microbial fuel cells (MFCs). Cathodes were constructed around either stainless steel (SS) mesh or copper mesh using PDMS as both catalyst binder and diffusion layer, and compared to cathodes of the same structure having a Nafion binder. With PDMS binder, copper mesh cathodes produced a maximum power of 1710 ± 1 mW m-2, while SS mesh had a slightly lower power of 1680 ± 12 mW m-2, with both values comparable to those obtained with Nafion binder. Cathodes with PDMS binder had stable power production of 1510 ± 22 mW m-2 (copper) and 1480 ± 56 mW m-2 (SS) over 15 days at cycle 15, compared to a 40% decrease in power with the Nafion binder. Cathodes with the PDMS binder had lower total cathode impedance than those with Nafion. This is due to a large decrease in diffusion resistance, because hydrophobic PDMS effectively prevented catalyst sites from filling up with water, improving oxygen mass transfer. The cost of PDMS is only 0.23% of that of Nafion. These results showed that PDMS is a very effective and low-cost alternative to Nafion binder that will be useful for large scale construction of these cathodes for MFC applications.

  16. Enhanced Performance in Flexible Binder-free SWCNT Membrane EDLC

    NASA Astrophysics Data System (ADS)

    Ma, Danhao; Shetty, Pralav; Adu, Kofi; Rajagopalan, Ramakrishnan

    2013-03-01

    We present results on an aqueous symmetric double layer electrochemical capacitor (EDLC) constructed with flexible binder-free single wall carbon (SWCNTs) membrane as electrodes. The capacitors were cycled from 0 to 1V @ 10 A/g for 10,000 cycles with 99.9% coulombic efficiency and 94% energy efficiency, and 100% depth of discharge. The power performance of the aqueous symmetric SWCNTs membrane capacitor is almost 100 -1000 times better than commercial non-aqueous EDLC capacitors. This work is supported by the Pennsylvania State, Altoona College Undergraduate Research Program and the Pennsylvania State Materials Research Institute at University Park, PA

  17. Biotechnologically engineered protein binders for applications in amyloid diseases.

    PubMed

    Haupt, Christian; Fändrich, Marcus

    2014-10-01

    The aberrant self-assembly of polypeptide chains into amyloid structures is a common phenomenon in several neurodegenerative diseases, systemic amyloidosis, and 'normal' aging. Improvements in laboratory-scale detection of these structures, their clinical diagnosis, and the treatment of disease likely depend on the advent of new molecules that recognize particular states or induce their clearance in vivo. This review will describe what biotechnology can do to generate proteinaceous amyloid-binders, explain their molecular recognition mechanisms, and summarize possibilities to functionalize further these ligands for specific applications.

  18. Injection molding of ceramics using a polyacetal based binder system

    SciTech Connect

    Ebenhoech, J.S.

    1996-06-01

    Among the production routes to small complex ceramic parts, powder injection molding is the most attractive alternative. It combines near net shape capability with good surface finish and is easy to automate. With the development of the catalytic debinding process for polyacetal binders, the main impediments for the acceptance of ceramic injection molding as a mass production method can be overcome. The use of this system ensures short molding cycle times, high green strength and fast debinding without deformation. Ready to mold compounds are commercially available for various oxide and non-oxide ceramic materials as well as the equipment needed for this process.

  19. Environmental impacts of asphalt mixes with electric arc furnace steel slag.

    PubMed

    Milačič, Radmila; Zuliani, Tea; Oblak, Tina; Mladenovič, Ana; Ančar, Janez Šč

    2011-01-01

    Electric arc furnace (EAF) steel slag can be used as an alternative high-quality material in road construction. Although asphalts with slag aggregates have been recognized as environmentally acceptable, there is a lack of data concerning the potential leaching of toxic Cr(VI) due to the highly alkaline media of EAF slag. Leaching of selected water extractable metals from slag indicated elevated concentrations of total chromium and Cr(VI). To estimate the environmental impacts of asphalt mixes with slag, leachability tests based on diffusion were performed using pure water and salt water as leaching agents. Compact and ground asphalt composites with natural aggregates, and asphalt composites in which the natural aggregates were completely replaced by slag were prepared. The concentrations of total chromium and Cr(VI) were determined in leachates over a time period of 6 mo. After 1 and 6 mo, the concentrations of some other metals were also determined in the leachates. The results indicated that chromium in leachates from asphalt composites with the addition of slag was present almost solely in its hexavalent form. However, the concentrations were very low (below 25 μg L) and did not represent an environmental burden. The leaching of other metals from asphalt composites with the addition of slag was negligible. Therefore, the investigated EAF slag can be considered as environmentally safe substitute for natural aggregates in asphalt mixes.

  20. Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China.

    PubMed

    Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

    2016-03-01

    In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase. PMID:27011196

  1. Estimates of air emissions from asphalt storage tanks and truck loading

    SciTech Connect

    Trumbore, D.C.

    1999-12-31

    Title V of the 1990 Clean Air Act requires the accurate estimation of emissions from all US manufacturing processes, and places the burden of proof for that estimate on the process owner. This paper is published as a tool to assist in the estimation of air emission from hot asphalt storage tanks and asphalt truck loading operations. Data are presented on asphalt vapor pressure, vapor molecular weight, and the emission split between volatile organic compounds and particulate emissions that can be used with AP-42 calculation techniques to estimate air emissions from asphalt storage tanks and truck loading operations. Since current AP-42 techniques are not valid in asphalt tanks with active fume removal, a different technique for estimation of air emissions in those tanks, based on direct measurement of vapor space combustible gas content, is proposed. Likewise, since AP-42 does not address carbon monoxide or hydrogen sulfide emissions that are known to be present in asphalt operations, this paper proposes techniques for estimation of those emissions. Finally, data are presented on the effectiveness of fiber bed filters in reducing air emissions in asphalt operations.

  2. Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China.

    PubMed

    Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

    2016-03-22

    In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase.

  3. The Potential of Heat Collection from Solar Radiation in Asphalt Solar Collectors in Malaysia

    NASA Astrophysics Data System (ADS)

    Beddu, Salmia; Talib, Siti Hidayah Abdul; Itam, Zarina

    2016-03-01

    The implementation of asphalt solar collectors as a means of an energy source is being widely studied in recent years. Asphalt pavements are exposed to daily solar radiation, and are capable of reaching up to 70°C in temperature. The potential of harvesting energy from solar pavements as an alternative energy source in replace of non-renewable energy sources prone to depletion such as fuel is promising. In Malaysia, the sun intensity is quite high and for this reason, absorbing the heat from sun radiation, and then utilizing it in many other applications such as generating electricity could definitely be impressive. Previous researches on the different methods of studying the effect of heat absorption caused by solar radiation prove to be quite old and inaffective. More recent findings, on the otherhand, prove to be more informative. This paper focuses on determining the potential of heat collection from solar radiation in asphalt solar collectors using steel piping. The asphalt solar collector model constructed for this research was prepared in the civil engineering laboratory. The hot mixed asphalt (HMA) contains 10% bitumen mixed with 90% aggregates of the total size of asphalt. Three stainless steel pipes were embedded into the interior region of the model according to the design criteria, and then put to test. Results show that harvesting energy from asphalt solar collectors proves highly potential in Malaysia due its the hot climate.

  4. Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China

    PubMed Central

    Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

    2016-01-01

    In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase. PMID:27011196

  5. Quantitative cancer risk assessment for occupational exposures to asphalt fumes during built-up roofing asphalt (BURA) operations.

    PubMed

    Rhomberg, Lorenz R; Mayfield, David B; Goodman, Julie E; Butler, Eric L; Nascarella, Marc A; Williams, Daniel R

    2015-01-01

    The International Agency for Research on Cancer qualitatively characterized occupational exposure to oxidized bitumen emissions during roofing as probably carcinogenic to humans (Group 2A). We examine chemistry, exposure, epidemiology and animal toxicity data to explore quantitative risks for roofing workers applying built-up roofing asphalt (BURA). Epidemiology studies do not consistently report elevated risks, and generally do not have sufficient exposure information or adequately control for confounders, precluding their use for dose-response analysis. Dermal carcinogenicity bioassays using mice report increased tumor incidence with single high doses. In order to quantify potential cancer risks, we develop time-to-tumor model methods [consistent with U.S. Environmental Protection Agency (EPA) dose-response analysis and mixtures guidelines] using the dose-time-response shape of concurrent exposures to benzo[a]pyrene (B[a]P) as concurrent controls (which had several exposure levels) to infer presumed parallel dose-time-response curves for BURA-fume condensate. We compare EPA relative potency factor approaches, based on observed relative potency of BURA to B[a]P in similar experiments, and direct observation of the inferred BURA dose-time-response (scaled to humans) as means for characterizing a dermal unit risk factor. We apply similar approaches to limited data on asphalt-fume inhalation and respiratory cancers in rats. We also develop a method for adjusting potency estimates for asphalts that vary in composition using measured fluorescence. Overall, the various methods indicate that cancer risks to roofers from both dermal and inhalation exposure to BURA are within a range typically deemed acceptable within regulatory frameworks. The approaches developed may be useful in assessing carcinogenic potency of other complex mixtures of polycyclic aromatic compounds. PMID:26515283

  6. Biofiltration of asphalt emissions: Full-scale operation treating off-gases from polymer-modified asphalt production

    SciTech Connect

    Cook, L.L.; Gostomski, P.A.; Apel, W.A.

    1999-09-30

    In response to complaints from nearby residents, a biofilter was designed, installed, and tested for treating odors in one of three odorous emission streams from an asphalt plant producing polymer-modified asphalt. Hydrogen sulfide (H{sub 2}S) was determined to be the most prevalent gaseous reduced sulfur compound and was detected in the emission stream only when polymer material was being added to raw asphalt. Emission stream H{sub 2}S concentrations were quite variable, ranging from 16 to approximately 30,000 ppm (v/v) and considered the likely compound contributing most to the plant's odor complaints. The biofilter was effective in controlling odor from the production process and removed an overall average of 65% of the H{sub 2}S during polymer addition, and for H{sub 2}S concentrations less than 400 ppmv, removal averaged 98%. These removal efficiencies reflect data from the biofilter operating at 2.5-minute empty bed residence time in 1996 and a 6.1-minute empty bed residence time in 1997. The biofilter's bed became increasingly acidified during the plant's 1997 operating season producing a pH gradient through the bed ranging from a high of 6.6 to a low of 3.1. The bed medium moisture content remained constant at about 60% (wet weight basis), but changes were observed in the water potential: no correlation to performance was determined. Changes in the microbial community reflected the bed acidification trend, with acidophiles becoming generally more numerous in the bed's deeper portions and in the mid to late season when the bed was most acidified. Bed acidification did not impact the biofilter's H{sub 2}S removal efficiency.

  7. Glass Transition and Molecular Mobility in Styrene-Butadiene Rubber Modified Asphalt.

    PubMed

    Khabaz, Fardin; Khare, Rajesh

    2015-11-01

    Asphalt, a soft matter consisting of more than a thousand chemical species, is of vital importance for the transportation infrastructure, yet it poses significant challenges for microscopic theory and modeling approaches due to its multicomponent nature. Polymeric additives can potentially enhance the thermo-mechanical properties of asphalt, thus helping reduce the road repair costs; rational design of such systems requires knowledge of the molecular structure and dynamics of these systems. We have used molecular dynamics (MD) simulations to investigate the volumetric, structural, and dynamic properties of the neat asphalt as well as styrene-butadiene rubber (SBR) modified asphalt systems. The volume-temperature behavior of the asphalt systems exhibited a glass transition phenomenon, akin to that observed in experiments. The glass transition temperature, room temperature density, and coefficient of volume thermal expansion of the neat asphalt systems so evaluated were in agreement with experimental data when the effect of the high cooling rate used in simulations was accounted for. While the volumetric properties of SBR modified asphalt were found to be insensitive to the presence of the SBR additive, the addition of SBR led to an increase in the aggregation of asphaltene molecules. Furthermore, addition of SBR caused a reduction in the mobility of the constituent molecules of asphalt, with the reduction being more significant for the larger constituent molecules. Similar to other glass forming liquids, the reciprocal of the diffusion coefficient of the selected molecules was observed to follow the Vogel-Fulcher-Tammann (VFT) behavior as a function of temperature. These results suggest the potential for using polymeric additives for enhancing the dynamic mechanical properties of asphalt without affecting its volumetric properties. PMID:26451630

  8. Habitat heterogeneity - biological association relationships in the asphalt volcano, SW Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Escobar, E.; Gaytan, A.

    2007-05-01

    A new class of cold seep, named asphalt volcano, was discovered in the Campeche Knolls region of the southern Gulf of Mexico, supporting chemosynthetic communities alike those lying at similar depth on the Angolan margin and the Barbados Prism suggesting an interesting longitudinal connectivity in the faunal components. The discovery of this novel deep-sea habitat has raised questions about diversity and process dynamics in this novel poorly described milieu. Results from two previous cruises jointly sponsored by German, US and Mexican funding agencies have allowed us to recognize the presence of large densities of background benthic megafauna, mainly represented by sea-cucumbers and galatheid crabs, which occupy diverse habitats in asphalt volcano and feed on microbial assemblages on the asphalt covering extended area. Asphalt displays different degrees of hardness suggesting ongoing activity of asphalt extrusion in the site that is reflected in biological benthic communities in different states succession and complexity. The fresh asphalt and the immediately surrounding soft sediment are colonized by mats of complex microbial assemblages where both background benthic megafauna and chemosynthetic tube worms and mussels aggregate. Our results focus on the diversity of the habitats associated with methane seepage through the example of geological structures in the asphalt volcano considering the small scale with the analysis of the relationships between biological assemblages and habitat heterogeneity assessing the role of the geological structure on biological communities. Bubbling of gas, oil and the content of thermogenic gas and gas hydrate in the asphalt suggests that the asphalt plays an important role as a reservoir of methane in this marginal deep sea.

  9. Group type analysis of asphalt by column liquid chromatography

    SciTech Connect

    Zhang, C.; Yang, J.; Xue, Y.; Li, Y.

    2008-07-01

    An improved analysis method for characterization of asphalt was established. The method is based on column chromatography technique. The asphalts were separated into four groups: saturates, aromatics, resins, and asphaltenes, quantitatively. About 0.1 g of sample was required in each analysis. About 20 mL of n-heptanes was used to separate out saturates first. Then about 35 mL of n-heptanes/dichloromethane (.5, v/v) mixture was used to separate out aromatics. About 30 mL of dichloromethane/tetrahydrofuran (1/3, v/v) mixture was used to separate out resin. The quality of the separation was confirmed by infrared spectra (IR) and {sup 1}H NMR analysis. The model compounds, tetracosan for saturates, dibenz(o)anthracen for aromatics, and acetanilide for resins were used for verification. The IR and {sup 1}H NMR analysis of the prepared fractions from the column liquid chromatography were in good agreement that of pure reagents.

  10. Recycled materials in asphalt pavements. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    Not Available

    1994-05-01

    The bibliography contains citations concerning the recycling of asphalt pavement materials, and the use of other recycled materials to manufacture asphalt pavement. Articles discuss methods used for recycling bituminous pavement including hot-mix and cold-mix. Materials used to improve recycled pavement, and recycled materials used in asphalt pavement include latexes, rubber scrap such as tires, glass shards, concretes, dusts, waste oils, roofing wastes, sulfur, and metal refining sludges. Testing and evaluation of recycled pavements both in laboratories and in test cases are considered. (Contains a minimum of 160 citations and includes a subject term index and title list.)

  11. Maturation trend in oils and asphalts of the Jordan Rift: Utilization of detailed vanadylporphyrin analysis

    NASA Astrophysics Data System (ADS)

    Aizenshtat, Zeev; Sundararaman, Padmanabhan

    1989-12-01

    A comparison of analytical methods for porphyrin analysis shows that high-performance liquid chromatography (HPLC) of intact vanadylporphyrins is more advantageous than, or superior to, mass spectral methods and is suited for routine analysis. HPLC has a higher resolving power compared with probe mass spectrometry. Detailed HPLC analysis of the vanadylporphyrins isolated from asphalts and oils from the Dead Sea area shows that the asphalts are products of early generation from an immature source rock. The light oils, Massada oil and Zuk Tamror, are more mature than the asphalts.

  12. Center for BioBased Binders and Pollution Reduction Technology

    SciTech Connect

    Thiel, Jerry

    2013-07-01

    Funding will support the continuation of the Center for Advanced Bio-based Binders and Pollution Reduction Technology Center (CABB) in the development of bio-based polymers and emission reduction technologies for the metal casting industry. Since the formation of the center several new polymers based on agricultural materials have been developed. These new materials have show decreases in hazardous air pollutants, phenol and formaldehyde as much as 50 to 80% respectively. The polymers termed bio-polymers show a great potential to utilize current renewable agricultural resources to replace petroleum based products and reduce our dependence on importing of foreign oil. The agricultural technology has shown drastic reductions in the emission of hazardous air pollutants and volatile organic compounds and requires further development to maintain competitive costs and productivity. The project will also research new and improved inorganic binders that promise to eliminate hazardous emissions from foundry casting operations and allow for the beneficial reuse of the materials and avoiding the burdening of overcrowded landfills.

  13. The Role of Binder in Deflagrating HMX-based Explosives

    NASA Astrophysics Data System (ADS)

    Tringe, J. W.; Levie, H. W.; Glascoe, E. A.; Greenwood, D. W.; de Haven, M. R.; Molitoris, J. D.; Springer, H. K.

    2011-06-01

    Deflagration rates are known to be a strong function of temperature and pressure, but chemical reactions facilitated by the explosive's binder can also play an important role. Here we report a study of two HMX-based formulations, PBX-9501 (HMX 95%, estane 2.5%, bdnpa 1.25%, and bdnpf 1.25%) and LX-10 (HMX 95%, Viton-A 5%), which we use to investigate the origins of violence in thermal explosions. We employ flash x-ray radiography to directly image the rates at which reaction fronts proceed in a confined vessel. Photonic Doppler velocimetry (PDV) characterizes the vessel wall motion as a function of time. Our results show that thermal explosions of PBX-9501, with its more reactive binder, are more violent than explosions of LX-10. In LX-10, we observe quenched deflagration and limited violence. In PBX-9501, however, a higher deflagration rate is developed and sustained even after vessel rupture. Thermal explosions of initially-confined PBX-9501 therefore are more complete and significantly more violent. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  14. 46 CFR 308.6 - Period of interim binders, updating application information and new applications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... with the American War Risk Agency, 14 Wall Street, New York, New York 10005. All interim binders on U.S... Wall Street, New York, New York 10005. All interim binders on foreign-flag vessels will become... information and new applications. 308.6 Section 308.6 Shipping MARITIME ADMINISTRATION, DEPARTMENT...

  15. 46 CFR 308.6 - Period of interim binders, updating application information and new applications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... with the American War Risk Agency, 14 Wall Street, New York, New York 10005. All interim binders on U.S... Wall Street, New York, New York 10005. All interim binders on foreign-flag vessels will become... information and new applications. 308.6 Section 308.6 Shipping MARITIME ADMINISTRATION, DEPARTMENT...

  16. 46 CFR 308.6 - Period of interim binders, updating application information and new applications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... with the American War Risk Agency, 14 Wall Street, New York, New York 10005. All interim binders on U.S... Wall Street, New York, New York 10005. All interim binders on foreign-flag vessels will become... information and new applications. 308.6 Section 308.6 Shipping MARITIME ADMINISTRATION, DEPARTMENT...

  17. Ductile Binder Phase For Use With Almgb14 And Other Hard Ceramic Materials

    DOEpatents

    Cook, Bruce A.; Russell, Alan; Harringa, Joel

    2005-07-26

    This invention relates to a ductile binder phase for use with AlMgB14 and other hard materials. The ductile binder phase, a cobalt-manganese alloy, is used in appropriate quantities to tailor good hardness and reasonable fracture toughness for hard materials so they can be used suitably in industrial machining and grinding applications.

  18. A review on using crumb rubber in reinforcement of asphalt pavement.

    PubMed

    Mashaan, Nuha Salim; Ali, Asim Hassan; Karim, Mohamed Rehan; Abdelaziz, Mahrez

    2014-01-01

    An immense problem affecting environmental pollution is the increase of waste tyre vehicles. In an attempt to decrease the magnitude of this issue, crumb rubber modifier (CRM) obtained from waste tyre rubber has gained interest in asphalt reinforcement. The use of crumb rubber in the reinforcement of asphalt is considered as a smart solution for sustainable development by reusing waste materials, and it is believed that crumb rubber modifier (CRM) could be an alternative polymer material in improving hot mix asphalt performance properties. In this paper, a critical review on the use of crumb rubber in reinforcement of asphalt pavement will be presented and discussed. It will also include a review on the effects of CRM on the stiffness, rutting, and fatigue resistance of road pavement construction.

  19. A Review on Using Crumb Rubber in Reinforcement of Asphalt Pavement

    PubMed Central

    Mashaan, Nuha Salim; Ali, Asim Hassan; Karim, Mohamed Rehan; Abdelaziz, Mahrez

    2014-01-01

    An immense problem affecting environmental pollution is the increase of waste tyre vehicles. In an attempt to decrease the magnitude of this issue, crumb rubber modifier (CRM) obtained from waste tyre rubber has gained interest in asphalt reinforcement. The use of crumb rubber in the reinforcement of asphalt is considered as a smart solution for sustainable development by reusing waste materials, and it is believed that crumb rubber modifier (CRM) could be an alternative polymer material in improving hot mix asphalt performance properties. In this paper, a critical review on the use of crumb rubber in reinforcement of asphalt pavement will be presented and discussed. It will also include a review on the effects of CRM on the stiffness, rutting, and fatigue resistance of road pavement construction. PMID:24688369

  20. Determination of the biodegradation rate of asphalt for the Hanford grout vaults. Hanford Grout Technology Program

    SciTech Connect

    Luey, J.; Li, S.W.

    1993-04-01

    Testing was initiated in March 1991 and completed in November 1992 to determine the rate at which asphalt is biodegraded by microorganisms native to the Hanford Site soils. The asphalt tested (AR-6000, US Oil, Tacoma, Washington) is to be used in the construction of a diffusion barrier for the Hanford grout vaults. Experiments to determine asphalt biodegradation rates were conducted using three separate test sets. These test sets were initiated in March 1991, January 1992, and June 1992 and ran for periods of 6 months, 11 months, and 6 months, respectively. The experimental method used was one originally developed by Bartha and Pramer (1965), and further refined by Bowerman et al. (1985), that determined the asphalt biodegradation rate through the measurement of carbon dioxide evolved.

  1. Study of chloride ion transport of composite by using cement and starch as a binder

    NASA Astrophysics Data System (ADS)

    Armynah, Bidayatul; Halide, Halmar; Zahrawani, Reski, Nurhadi; Tahir, Dahlang

    2016-03-01

    This study presents the chemical bonding and the structural properties of composites from accelerator chloride test migration (ACTM). The volume fractions between binder (cement and starch) and charcoal in composites are 20:80 and 60:40. The effect of the binder to the chemical composition, chemical bonding, and structural properties before and after chloride ion passing through the composites was determined by X-ray fluorescence (XRF), by Fourier transform infra-red (FTIR), and x-ray diffraction (XRD), respectively. From the XRD data, XRF data, and the FTIR data shows the amount of chemical composition, the type of binding, and the structure of composites are depending on the type of binder. The amount of chloride migration using starch as binder is higher than that of cement as a binder due to the density effects.

  2. A multiscale model for predicting the viscoelastic properties of asphalt concrete

    NASA Astrophysics Data System (ADS)

    Garcia Cucalon, Lorena; Rahmani, Eisa; Little, Dallas N.; Allen, David H.

    2016-08-01

    It is well known that the accurate prediction of long term performance of asphalt concrete pavement requires modeling to account for viscoelasticity within the mastic. However, accounting for viscoelasticity can be costly when the material properties are measured at the scale of asphalt concrete. This is due to the fact that the material testing protocols must be performed recursively for each mixture considered for use in the final design.

  3. The effect of different types of abdominal binders on intra-abdominal pressure

    PubMed Central

    Zhang, Hua-Yu; Liu, Dong; Tang, Hao; Sun, Shi-Jin; Ai, Shan-Mu; Yang, Wen-Qun; Jiang, Dong-Po; Zhang, Lian-Yang

    2016-01-01

    Objectives: To investigate the effect of non-elastic/elastic abdominal binders on intra-vesical pressure (IVP), physiological functions, and clinical outcomes in laparotomy patients at the perioperative stage. Methods: This prospective study was conducted from May to October 2014 at the Trauma Surgery Department, Daping Hospital, Chongqing, China. Laparotomy patients were randomly divided into non-elastic abdominal binder group (28 patients), and elastic abdominal binder group (29 patients). Binders were applied for 14 days following the operation, or until discharge. Demographic information, Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE-II) scores (prior to the operation, on the first day after operation, the day IVP measurement was stopped, and one day before discharge), and outcomes were recorded. The IVP was measured before the operation to postoperative day 7. Results: There were no significant differences in the demographic information, outcomes, SOFA or APACHE-II scores between the 2 groups. Initial out-of-bed mobilization occurred earlier in the elastic binder group (3.2 ± 2.0 versus 5.0 ± 3.7 days, p=0.028). A greater increase in IVP was observed in the non-elastic binder group than in the elastic binder group (2.9 ± 1.1 versus 1.1 ± 0.7 mm Hg, p=0.000). Conclusion: Elastic binders have relatively little effect on IVP and are more helpful at promoting postoperative recovery than non-elastic binders. Therefore, elastic binders are more suitable for clinical use. PMID:26739977

  4. Thermal Degradation Studies of A Polyurethane Propellant Binder

    SciTech Connect

    Assink, R.A.; Celina, M.; Gillen, K.T.; Graham, A.C.; Minier, L.M.

    1999-06-12

    The thermal oxidative aging of a crosslinked hydroxy-terminated polybutadiene (HTPB)/isophorone diisocyanate (IPDI) based polyurethane rubber, used as a polymeric binder in solid propellant grain, was investigated at temperatures from 25 C to 125 C. The changes in tensile elongation, polymer network properties and chain dynamics, mechanical hardening and density were determined with a range of techniques including modulus profiling, solvent swelling, NMR relaxation and O{sub 2} permeability measurements. We critically evaluated the Arrhenius methodology that is commonly used with a linear extrapolation of high temperature aging data using extensive data superposition and highly sensitive oxygen consumption experiments. The effects of other constituents in the propellant formulation on aging were also investigated. We conclude that crosslinking is the dominant process at higher temperatures and that the degradation involves only limited hardening in the bulk of the material. Significant curvature in the Arrhenius diagram of the oxidation rates was observed. This is similar to results for other rubber materials.

  5. Graphite fluoride as a solid lubricant in a polyimide binder

    NASA Technical Reports Server (NTRS)

    Fusaro, R. L.; Sliney, H. E.

    1972-01-01

    Polyimide resin (PI) was shown to be a suitable binder material for the solid lubricant graphite fluoride, (CF(1.1))n. Comparisons were made to similar tests using PI-bonded MOS2 films, graphite fluoride rubbed films, and MOS2 rubbed films. The results showed that, at any one specific temperature between 25 and 400 C, the wear life of PI-bonded graphite fluoride films exceeded those of the other three films by at least a factor of 2 and by as much as a factor of 60. Minimum friction coefficients for the PI-bonded films were 0.08 for graphite fluoride and 0.04 for MOS2. The rider wear rates for the two PI-bonded films at 25 C were nearly equal.

  6. Evaluation of a biomass-derived oil for use as additive in paving asphalt

    SciTech Connect

    Houde, J. Jr.; Clelland, I.; Sawatzky, H.

    1995-12-31

    A biomass derived oil referred to as sludge derived oil (SDO) has been evaluated to determine its potential use as an asphalt cement additive. The oil is derived from a relatively low temperature (450{degrees}C) atmospheric pressure thermoconversion process called Enersludge. The Enersludge process converts dried sewage sludge to a liquid hydrocarbon fraction. Relatively high concentrations of polar groups were identified in extensive characterization tests which indicated SDO could be utilized as an additive for asphalt. The oil`s unique properties make it a antistripping additive. Also, its strong affinity for heavy asphaltic material makes it an ideal rejuvenating agent for recycled asphalt. The SDO performed as well as the commercial antistripping asphalt additives tested in static immersion stripping tests. Laboratory-scale tests have shown that the strength of asphalt concrete produced using SDO is similar to that produced using commercial additives. In September 1994 SDO was used to pave a test strip in Quebec, Canada. This paper describes the work done at ERL/CANMET to develop SDO for antistripping applications.

  7. Investigation of Low Heat Accumulation Asphalt Mixture and Its Impact on Urban Heat Environment.

    PubMed

    Xie, Jianguang; Yang, Zhaoxu; Liang, Leilei

    2015-01-01

    This study is focused on investigating the effectiveness of low heat accumulation asphalt mixture and its impact on the urban heat environment. Infrared radiation experiments showed that the temperature of the asphalt mixture decreased with the increase in far-infrared radiant material. The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity. The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%. Moreover, the low-temperature splitting tensile strength of the asphalt mixture with 6% far-infrared radiation material increased by 21.3%. The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively. PMID:26222762

  8. Screening of crude oils for asphalt precipitation: Theory, practice, and the selection of inhibitors

    SciTech Connect

    Boer, R.B. de; Leerlooyer, K.; Bergen, A.R.D. van ); Eigner, M.R.P.

    1995-02-01

    This paper describes a simple method to screen crude oils for their tendency to precipitate asphalt, which may cause problems during production. The method is based on a thermodynamic model of asphalt solubility, derived earlier by Flory and Huggins. The most important parameters in this model are the Hildebrand solubility parameters for oil and asphaltene, and their molar volumes. The oil parameters can all be correlated with the in-situ density of the crude. It is shown that heavy crudes usually will give fewer problems with asphalt precipitation, despite their higher asphaltene content, certainly if the reservoir pressure is close to bubblepoint pressure. Consequently, the tendency for asphalt precipitation is mainly determined by three parameters: the extent to which the crude is undersaturated with gas, the density of the crude at reservoir conditions, and its saturation with asphalt at downhole conditions. Apart from the simple screening method, more elaborate methods are described to assess the potential for asphalt precipitation more accurately; asphaltene analysis on produced reservoir fluid and tank oil; n-heptane titration of the tank oil; visual inspection of a bottom-hole sample in a high-pressure cell during pressure reduction; and dynamic flow tests on tank oil after n-heptane addition.

  9. Road Asphalt Pavements Analyzed by Airborne Thermal Remote Sensing: Preliminary Results of the Venice Highway

    PubMed Central

    Pascucci, Simone; Bassani, Cristiana; Palombo, Angelo; Poscolieri, Maurizio; Cavalli, Rosa

    2008-01-01

    This paper describes a fast procedure for evaluating asphalt pavement surface defects using airborne emissivity data. To develop this procedure, we used airborne multispectral emissivity data covering an urban test area close to Venice (Italy).For this study, we first identify and select the roads' asphalt pavements on Multispectral Infrared Visible Imaging Spectrometer (MIVIS) imagery using a segmentation procedure. Next, since in asphalt pavements the surface defects are strictly related to the decrease of oily components that cause an increase of the abundance of surfacing limestone, the diagnostic absorption emissivity peak at 11.2μm of the limestone was used for retrieving from MIVIS emissivity data the areas exhibiting defects on asphalt pavements surface.The results showed that MIVIS emissivity allows establishing a threshold that points out those asphalt road sites on which a check for a maintenance intervention is required. Therefore, this technique can supply local government authorities an efficient, rapid and repeatable road mapping procedure providing the location of the asphalt pavements to be checked.

  10. Investigation of Low Heat Accumulation Asphalt Mixture and Its Impact on Urban Heat Environment

    PubMed Central

    Xie, Jianguang; Yang, Zhaoxu; Liang, Leilei

    2015-01-01

    This study is focused on investigating the effectiveness of low heat accumulation asphalt mixture and its impact on the urban heat environment. Infrared radiation experiments showed that the temperature of the asphalt mixture decreased with the increase in far-infrared radiant material. The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity. The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%. Moreover, the low-temperature splitting tensile strength of the asphalt mixture with 6% far-infrared radiation material increased by 21.3%. The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively. PMID:26222762

  11. A study on engineering characteristics of asphalt concrete using filler with recycled waste lime.

    PubMed

    Sung Do, Hwang; Hee Mun, Park; Suk keun, Rhee

    2008-01-01

    This study focuses on determining the engineering characteristics of asphalt concrete using mineral fillers with recycled waste lime, which is a by-product of the production of soda ash (Na(2)CO(3)). The materials tested in this study were made using a 25%, 50%, 75%, and 100% mixing ratio based on the conventional mineral filler ratio to analyze the possibility of using recycled waste lime. The asphalt concretes, made of recycled waste lime, hydrated lime, and conventional asphalt concrete, were evaluated through their fundamental engineering properties such as Marshall stability, indirect tensile strength, resilient modulus, permanent deformation characteristics, moisture susceptibility, and fatigue resistance. The results indicate that the application of recycled waste lime as mineral filler improves the permanent deformation characteristics, stiffness and fatigue endurance of asphalt concrete at the wide range of temperatures. It was also determined that the mixtures with recycled waste lime showed higher resistance against stripping than conventional asphalt concrete. It was concluded from various test results that a waste lime can be used as mineral filler and, especially, can greatly improve the resistance of asphalt concrete to permanent deformation at high temperatures. PMID:17408942

  12. A study on engineering characteristics of asphalt concrete using filler with recycled waste lime.

    PubMed

    Sung Do, Hwang; Hee Mun, Park; Suk keun, Rhee

    2008-01-01

    This study focuses on determining the engineering characteristics of asphalt concrete using mineral fillers with recycled waste lime, which is a by-product of the production of soda ash (Na(2)CO(3)). The materials tested in this study were made using a 25%, 50%, 75%, and 100% mixing ratio based on the conventional mineral filler ratio to analyze the possibility of using recycled waste lime. The asphalt concretes, made of recycled waste lime, hydrated lime, and conventional asphalt concrete, were evaluated through their fundamental engineering properties such as Marshall stability, indirect tensile strength, resilient modulus, permanent deformation characteristics, moisture susceptibility, and fatigue resistance. The results indicate that the application of recycled waste lime as mineral filler improves the permanent deformation characteristics, stiffness and fatigue endurance of asphalt concrete at the wide range of temperatures. It was also determined that the mixtures with recycled waste lime showed higher resistance against stripping than conventional asphalt concrete. It was concluded from various test results that a waste lime can be used as mineral filler and, especially, can greatly improve the resistance of asphalt concrete to permanent deformation at high temperatures.

  13. Use of ground-penetrating radar for asphalt thickness determination

    NASA Astrophysics Data System (ADS)

    Choubane, Bouzid; Fernando, Emmanuel; Ross, Stephen C.; Dietrich, Bruce T.

    2003-07-01

    A computer program, called TERRA (Thickness Evaluation of Roads by RAdar) was recently developed for estimating pavement layer thicknesses from ground penetrating radar (GPR) data. This program incorporates decision criteria for automated detection of layer interfaces, computation of layer thicknesses and a segmentation algorithm for delineating segments based on layer thicknesses. The Florida Department of Transportation (FDOT) initiated the present field study for an initial assessment of TERRA. Radar and core data were collected from several flexible pavement sections of Florida's roadway system. These sites were selected to represent the present Florida in-place mixes (Superpave and Marshall mixtures) and different asphalt layer thicknesses, which varied from approximately 50 to 300 mm (2 to 12 in). Radar data were collected at both highway speeds and in stationary mode. This paper presents a description of the data collection effort as well as the subsequent analysis and findings.

  14. Legionellosis Outbreak Associated with Asphalt Paving Machine, Spain, 2009

    PubMed Central

    Fenollar, José; Escribano, Isabel; González-Candelas, Fernando

    2010-01-01

    From 1999 through 2005 in Alcoi, Spain, incidence of legionellosis was continually high. Over the next 4 years, incidence was lower, but an increase in July 2009 led health authorities to declare an epidemic outbreak. A molecular epidemiology investigation showed that the allelic profiles for all Legionella pneumophila samples from the 2009 outbreak patients were the same, thus pointing to a common genetic origin for their infections, and that they were identical to that of the organism that had caused the previous outbreaks. Spatial-temporal and sequence-based typing analyses indicated a milling machine used in street asphalt repaving and its water tank as the most likely sources. As opposed to other machines used for street cleaning, the responsible milling machine used water from a natural spring. When the operation of this machine was prohibited and cleaning measures were adopted, infections ceased. PMID:20735921

  15. Lignite slime as activator in production of oxidized asphalts

    SciTech Connect

    Gureev, A.A.; Gorlov, E.G.; Leont'eva, O.B.; Zotova, O.V.

    1988-03-01

    The possibility of activation of the oxidation of straight-run resids to asphalts by the addition of lignite slimes obtained in the liquefaction of coals of the Kansk-Achinsk basin was studied on the basis of a hypothesis formulated with due regard for the principles of physicochemical mechanics of petroleum disperse systems. A reduction of the air bubble size in the oxidizing vessel should lead to an increase in the total surface of oxidation and hence to a shortening of the time required for oxidation of the feed. A straight-run vacuum resid from mixed West Siberian and Ukhta crudes was used. The resid was oxidized with and without the addition of slime.

  16. Characteristics of dynamic triaxial testing of asphalt mixtures

    NASA Astrophysics Data System (ADS)

    Ulloa Calderon, Alvaro

    Due to the increasing traffic loads and tire pressures, a serious detrimental impact has occurred on flexible pavements in the form of excessive permanent deformation once the critical combination of loading and environmental conditions are reached. This distress, also known as rutting, leads to an increase in road roughness and ultimately jeopardizes the road users' safety. The flow number (FN) simple performance test for asphalt mixtures was one of the final three tests selected for further evaluation from the twenty-four test/material properties initially examined under the NCHRP 9-19 project. Currently, no standard triaxial testing conditions in terms of the magnitude of the deviator and confining stresses have been specified. In addition, a repeated haversine axial compressive load pulse of 0.1 second and a rest period of 0.9 second are commonly used as part of the triaxial testing conditions. The overall objective of this research was to define the loading conditions that created by a moving truck load in the hot mixed asphalt (HMA) layer. The loading conditions were defined in terms of the triaxial stress levels and the corresponding loading time. Dynamic mechanistic analysis with circular stress distribution was used to closely simulate field loading conditions. Extensive mechanistic analyses of three different asphalt pavement structures subjected to moving traffic loads at various speeds and under braking and non-braking conditions were conducted using the 3D-Move model. Prediction equations for estimating the anticipated deviator and confining stresses along with the equivalent deviator stress pulse duration as a function of pavement temperature, vehicle speed, and asphalt mixture's stiffness have been developed. The magnitude of deviator stress, sigmad and confining stress, sigmac, were determined by converting the stress tensor computed in the HMA layer at 2" below pavement surface under a moving 18-wheel truck using the octahedral normal and shear

  17. Legionellosis outbreak associated with asphalt paving machine, Spain, 2009.

    PubMed

    Coscollá, Mireia; Fenollar, José; Escribano, Isabel; González-Candelas, Fernando

    2010-09-01

    From 1999 through 2005 in Alcoi, Spain, incidence of legionellosis was continually high. Over the next 4 years, incidence was lower, but an increase in July 2009 led health authorities to declare an epidemic outbreak. A molecular epidemiology investigation showed that the allelic profiles for all Legionella pneumophila samples from the 2009 outbreak patients were the same, thus pointing to a common genetic origin for their infections, and that they were identical to that of the organism that had caused the previous outbreaks. Spatial-temporal and sequence-based typing analyses indicated a milling machine used in street asphalt repaving and its water tank as the most likely sources. As opposed to other machines used for street cleaning, the responsible milling machine used water from a natural spring. When the operation of this machine was prohibited and cleaning measures were adopted, infections ceased.

  18. Use of tertiary nitrogen heterocyclic material to reduce moisture-induced damage in asphalt-aggregate mixtures

    SciTech Connect

    Plancher, H.; Petersen, J.C.

    1981-01-15

    Asphalt-aggregate roads crack when subjected to freezing and thawing cycles. Herein, the useful life of asphalts are substantially improved by a minor amount of a moisture damage inhibiting agent selected from compounds having a pyridine moiety, including acid salts of such compounds. A shale oil fraction may serve as the source of the improving agent and may simply be blended with conventional petroleum asphalts.

  19. Biofiltration of Asphalt Emissions: Full-scale Operation Treating Off-gases from Polymer-modified Asphalt Production

    SciTech Connect

    Cook, Lawrence Leslie; Apel, William Arnold; Gostomski, P. A.

    2004-04-01

    In response to complaints from nearby residents, a biofilter was designed, installed, and tested for treating odors in one of three odorous emission streams from an asphalt plant producing polymer-modified asphalt. Hydrogen sulfide (H2S) was determined to be the most prevalent gaseous reduced sulfur compound and was detected in the emission stream only when polymer material was being added to raw asphalt. Emission stream H2S concentrations we requite variable, ranging from 16 to approximately 30,000 ppm (v/v) and considered the likely compound contributing most to the plant's odor complaints. The biofilter was effective in controlling odor from the production process and removed an overall average of 65% of the H2S during polymer addition, and for H2S concentrations less than 400 ppmv, re m oval averaged 98%. These removal efficiencies reflect data from the biofilter operating at 2.5-minute empty bed residence time in 1996 and a 6.1-minute empty bed residence time in 1997. The biofilter's bed became increasingly acidified during the plant's 1997 operating season producing a pH gradient through the bed ranging from a high of 6.6 to a low of 3.1. The bed medium moisture content remained constant at about 60% (wet weight basis), but changes were observed in the water potential: no correlation to performance was determined. Changes in the microbial community reflected the bed acidification trend, with acidophiles becoming gene rally more numerous in the bed's deeper portions and in the mid to late season when the bed was most acidified. Bed acidification did not impact the biofilter's H2S removal efficiency. Nearby residents we resurveyed and roughly half of the respondents indicated that the odor conditions had improved, one-third felt odor conditions were unchanged and the remaining 15% felt odor conditions were worse despite the fact that only one of three of the plant's odorous emission streams were treated by the biofilter. Plans are to implement biofiltration for

  20. Nuclear method for determination of asphalt content corrected for moisture in bituminous mixture. Final report, March 1988-February 1989

    SciTech Connect

    Christensen, D.W.; Tarris, J.P.

    1989-05-01

    This report presents results of research on the development of a method for determination of asphalt content corrected for moisture using the nuclear-gauge method. The researchers selected an approach that involved rapid drying of the asphalt concrete samples in a microwave oven prior to the determination of asphalt content using a Troxler Model 3241-C nuclear asphalt-content gauge. As a reference, asphalt contents were also measured using quantitative extraction. In general, good agreement was found between asphalt contents measured by the Troxler Model 3241-C nuclear gauge and asphalt contents measured by quantitative extraction. In extended sampling for Plant 1, no significant increase in nuclear gauge error was seen over a 10-day sampling period, which indicates that daily calibration of the nuclear gauge is probably unnecessary to maintain satisfactory performance. The field demonstration of the procedure of drying the bituminous mixture in a microwave oven and then determining its asphalt content by the nuclear method indicated asphalt-content results were obtained approximately 1 hour faster than results obtained by quantitative extraction.

  1. Predicting rheological parameters of reclaimed asphalt cement with wave propagation techniques. Research report, 1 September 1993-31 August 1995

    SciTech Connect

    Nazarian, S.; Pezo, R.; Nori, S.R.G.; Picornell, M.

    1996-07-01

    A methodology to predict the rheological of asphalt cement from elastic modulus or from the indirect tensile (IDT) strength of the mix is presented. Wave propagation techniques were used to determine the modulus of the mix. Numerous specimens, prepared from four different mixtures with different asphalt contents and voids in the total mixes (VTM`s), were-oven aged for different periods. The elastic modulus and IDT strength of each specimen were determined, and its asphalt cement was recovered to evalutate its rheological properties. The effects of different parameters, such as asphalt content and VTM, on relationships between elastic modulus or IDT strength with rheological properties were determined.

  2. Effects of paving asphalt fume exposure on genotoxic and mutagenic activities in the rat lung.

    PubMed

    Zhao, H W; Yin, X J; Frazer, D; Barger, M W; Siegel, P D; Millecchia, L; Zhong, B Z; Tomblyn, S; Stone, S; Ma, J K H; Castranova, V; Ma, J Y C

    2004-02-14

    Asphalt fumes are complex mixtures of aerosols and vapors containing various organic compounds, including polycyclic aromatic hydrocarbons (PAHs). Previously, we have demonstrated that inhalation exposure of rats to asphalt fumes resulted in dose-dependent induction of CYP1A1 with concomitant down-regulation of CYP2B1 and increased phase II enzyme quinone reductase activity in the rat lung. In the present study, the potential genotoxic effects of asphalt fume exposure due to altered lung microsomal enzymes were studied. Rats were exposed to air or asphalt fume generated under road paving conditions at various concentrations and sacrificed the next day. Alveolar macrophages (AM) were obtained by bronchoalveolar lavage and examined for DNA damage using the comet assay. To evaluate the systemic genotoxic effect of asphalt fume, micronuclei formation in bone marrow polychromatic erythrocytes (PCEs) was monitored. Lung S9 from various exposure groups was isolated from tissue homogenates and characterized for metabolic activity in activating 2-aminoanthracene (2-AA) and benzo[a]pyrene (BaP) mutagenicity using the Ames test with Salmonella typhimurium YG1024 and YG1029. This study showed that the paving asphalt fumes significantly induced DNA damage in AM, as revealed by DNA migration in the comet assay, in a dose-dependent manner, whereas the micronuclei formation in bone marrow PCEs was not detected even at a very high exposure level (1733 mg h/m3). The conversion of 2-AA to mutagens in the Ames test required lung S9-mediated metabolic activation in a dose-dependent manner. In comparison to the controls, lung S9 from rats exposed to asphalt fume at a total exposure level of 479+/-33 mg h/m3 did not significantly enhance 2-AA mutagenicity with either S. typhimurium YG1024 or YG1029. At a higher total asphalt fume exposure level (1150+/-63 mg h/m3), S9 significantly increased the mutagenicity of 2-AA as compared to the control. However, S9 from asphalt fume-exposed rats

  3. Preparation of Fiber Based Binder Materials to Enhance the Gas Adsorption Efficiency of Carbon Air Filter.

    PubMed

    Lim, Tae Hwan; Choi, Jeong Rak; Lim, Dae Young; Lee, So Hee; Yeo, Sang Young

    2015-10-01

    Fiber binder adapted carbon air filter is prepared to increase gas adsorption efficiency and environmental stability. The filter prevents harmful gases, as well as particle dusts in the air from entering the body when a human inhales. The basic structure of carbon air filter is composed of spunbond/meltblown/activated carbon/bottom substrate. Activated carbons and meltblown layer are adapted to increase gas adsorption and dust filtration efficiency, respectively. Liquid type adhesive is used in the conventional carbon air filter as a binder material between activated carbons and other layers. However, it is thought that the liquid binder is not an ideal material with respect to its bonding strength and liquid flow behavior that reduce gas adsorption efficiency. To overcome these disadvantages, fiber type binder is introduced in our study. It is confirmed that fiber type binder adapted air filter media show higher strip strength, and their gas adsorption efficiencies are measured over 42% during 60 sec. These values are higher than those of conventional filter. Although the differential pressure of fiber binder adapted air filter is relatively high compared to the conventional one, short fibers have a good potential as a binder materials of activated carbon based air filter.

  4. Prevention of 11-deoxycorticosterone-salt-induced glomerular hypertrophy and glomerulosclerosis by dietary phosphate binder.

    PubMed Central

    Shimamura, T.

    1990-01-01

    The effects of dietary phosphate binder on deoxycorticosterone (DOC)-salt-hypertensive rats were examined. DOC-treated and non-DOC-treated rats were fed the diet either with or without phosphate binder, dihydroxyaluminum aminoacetate. All rats drank 1% NaCl. DOC-salt-treated rats without binder demonstrated marked glomerular hypertrophy, many globally sclerosed glomeruli, severe proteinuria, focal cardiac fibrosis, and splenomegaly. A significant reduction of glomerular hypertrophy, glomerulosclerosis, severity of proteinuria, splenomegaly, and the myocardial lesion took place when the DOC-salt-treated rats were given phosphate binder. The globally sclerosed glomeruli exhibited remarkable hypertrophy while structurally preserved glomeruli showed little evidence of enlargement. The plasma phosphate level was low in rats with dietary phosphate binder. In conclusion, the dietary phosphate binder ameliorated glomerular hypertrophy, glomerulosclerosis, proteinuria, myocardial fibrosis, and splenomegaly occurring in DOC-salt-treated rats. The data indicated that there was an association between glomerular hypertrophy and glomerulosclerosis in this model. The exact mechanisms of action of the phosphate binder, however, remain far from clear. Images Figure 1 Figure 2 Figure 3 Figure 6 Figure 7 Figure 8 PMID:2316624

  5. The effect of the physical states of binders on high-shear wet granulation and granule properties: a mechanistic approach towards understanding high-shear wet granulation process. Part I. Physical characterization of binders.

    PubMed

    Li, Jinjiang; Tao, Li; Dali, Mandar; Buckley, David; Gao, Julia; Hubert, Mario

    2011-01-01

    In this study, the objective is to investigate the effect of the physical state of a binder on wet granulation and granule properties using a binary model system (CaCO(3)-binder), which is essential for understanding the mechanism of wet granulation when binder is added in a dry state. Part I focus on studying the phase behavior or the physical state change of four binders: PVP K12, K29/32, HPC, and HPMC, after exposure to either moisture or liquid water. Their interaction with water was studied by measuring the water sorption of binders and the binary blends of CaCO(3)-binder. Changes in the physical states of the binders at room temperature as a function of water content was monitored via dialysis experiments, and characterized by determining the glass transition temperatures (T(g)) of the binders with water. The results suggest that the PVP binders can absorb more water than the cellulosic binders which is same for binder alone and in the binary blends. PVP K12 undergoes a phase transition from the glassy state to the rubbery/solution state at much lower water content than PVP K29/32 (10% vs. 20%) at room temperature. The phase transition for HPC occurs with 10-15% water based on rheological measurements. PMID:20575065

  6. Effects of ageing on different binders for retouching and on some binder-pigment combinations used for restoration of wall paintings

    SciTech Connect

    Ropret, P. Zoubek, R.; Skapin, A. Sever Bukovec, P.

    2007-11-15

    In restoration of colour layers, the selection of the most appropriate retouching binder is a very important step that may have a crucial impact on materials durability. As different weather conditions can have versatile influence on stability of colour layers, we determined the effect of ageing on carefully selected samples of binders (Tylose, Klucel, ammonium caseinate, gum arabicum, fish and skin glues and some other synthetic binders) as well as on several binder-pigment combinations (the pigments in combinations being cinnabar, green earth and smalt). The samples were subjected to accelerated ageing tests in climatic chambers. In these tests the temperature and the relative humidity were daily oscillating between - 20 deg. C and 50 deg. C and 50% to 90%, respectively, for a period of one month. Then the samples were exposed to UV and visible light generated by a metal halide lamp for a month. The differences in microstructure before and after ageing were determined by optical and scanning electron microscopy, while the ageing of the organic structures in binders was investigated by Fourier transform infrared (FTIR) microscopy.

  7. Study on catalysis effect of TEPB on the curing reaction of HTPB binder system

    NASA Astrophysics Data System (ADS)

    Chang, S. J.; Tang, J.; Liu, X.; Yan, W.

    2016-07-01

    The catalysis effect of tri (exhoxyphenyl) bismuthine (TEPB) on the curing reaction of HTPB binder system was studied by using DSC method. The curing peak temperatures of the catalyst systems were measured to calculate kinetic parameters by using Kissinger and Crane methods, respectively. Two curing reaction kinetic equations were established. The results show that TEPB has high catalytic activity and can decrease the curing temperature of HTPB binder system, down to 35 °C, in which the optimum volume of TEPB is 0.5% of HTPB binder system.

  8. Do aluminium-based phosphate binders continue to have a role in contemporary nephrology practice?

    PubMed Central

    2011-01-01

    Background Aluminium-containing phosphate binders have long been used for treatment of hyperphosphatemia in dialysis patients. Their safety became controversial in the early 1980's after reports of aluminium related neurological and bone disease began to appear. Available historical evidence however, suggests that neurological toxicity may have primarily been caused by excessive exposure to aluminium in dialysis fluid, rather than aluminium-containing oral phosphate binders. Limited evidence suggests that aluminium bone disease may also be on the decline in the era of aluminium removal from dialysis fluid, even with continued use of aluminium binders. Discussion The K/DOQI and KDIGO guidelines both suggest avoiding aluminium-containing binders. These guidelines will tend to promote the use of the newer, more expensive binders (lanthanum, sevelamer), which have limited evidence for benefit and, like aluminium, limited long-term safety data. Treating hyperphosphatemia in dialysis patients continues to represent a major challenge, and there is a large body of evidence linking serum phosphate concentrations with mortality. Most nephrologists agree that phosphate binders have the potential to meaningfully reduce mortality in dialysis patients. Aluminium is one of the cheapest, most effective and well tolerated of the class, however there are no prospective or randomised trials examining the efficacy and safety of aluminium as a binder. Aluminium continues to be used as a binder in Australia as well as some other countries, despite concern about the potential for toxicity. There are some data from selected case series that aluminium bone disease may be declining in the era of reduced aluminium content in dialysis fluid, due to rigorous water testing. Summary This paper seeks to revisit the contemporary evidence for the safety record of aluminium-containing binders in dialysis patients. It puts their use into the context of the newer, more expensive binders and increasing

  9. GPR in Nondestructive Quality Assurance of New Asphalt Pavements

    NASA Astrophysics Data System (ADS)

    Poikajärvi, J.; Peisa, K.; Narbro, A.

    2012-04-01

    Mara Nord is an international cooperation project financed by Interreg IVA Nord funding program with partners from Finland, Sweden and Norway. One of the objectives in Mara Nord project has been to research the quality assurance of new asphalt pavement. Ground penetrating radar (GPR) survey is used as an alternative method for coring in quality assurance. There exist numerous advantages for the use of GPR. For example, the fluent measuring arrangements without closing the traffic on the road and the extensive continuous profile that can be constructed from the measuring data. Within the framework of Mara Nord Project field tests were organized in Seinäjoki region in Finland on August 2011. The tests were done by four consulting companies from Finland and Rovaniemi University of Applied Sciences. The aim of these tests was to compare the measured dielectric value profiles and the calculated void content profiles of the equipment. The tested equipment was GSSI manufactured SIR-20 and 1 GHz horn antennas. Void content values were calculated using the model presented by Mr. Roimela (1997). All core samples were taken from the right wheel path. The same reference core samples were used when analyzing the data of each GPR equipment. Some samples were taken right after the pavement work was completed with the rest three weeks after during the test measurements. The tests indicated that GPRs have very good repeatability in measuring dielectric changes on top surface layers of asphalt pavements. Furthermore, different GPRs locate the same detectable longitudinal dielectric changes with high accuracy. Some differences were found in the dielectric value levels, yet reproducibility of the calculated void content values was quite good. The test data was also used to evaluate the reliability of the regression model between the dielectric values measured through GPR and the void content of the pavement determined from reference cores. Test data indicated that accurate regression

  10. Process Development of Porcelain Ceramic Material with Binder Jetting Process for Dental Applications

    NASA Astrophysics Data System (ADS)

    Miyanaji, Hadi; Zhang, Shanshan; Lassell, Austin; Zandinejad, Amirali; Yang, Li

    2016-03-01

    Custom ceramic structures possess significant potentials in many applications such as dentistry and aerospace where extreme environments are present. Specifically, highly customized geometries with adequate performance are needed for various dental prostheses applications. This paper demonstrates the development of process and post-process parameters for a dental porcelain ceramic material using binder jetting additive manufacturing (AM). Various process parameters such as binder amount, drying power level, drying time and powder spread speed were studied experimentally for their effect on geometrical and mechanical characteristics of green parts. In addition, the effects of sintering and printing parameters on the qualities of the densified ceramic structures were also investigated experimentally. The results provide insights into the process-property relationships for the binder jetting AM process, and some of the challenges of the process that need to be further characterized for the successful adoption of the binder jetting technology in high quality ceramic fabrications are discussed.

  11. Chemical Characterization of Lime-Based Binders in Historic Buildings of Latvia

    NASA Astrophysics Data System (ADS)

    Kirilovica, I.; Gulbe, L.; Vitina, I.; Igaune-Blumberga, S.

    2015-11-01

    The aim of this research is to investigate the chemical composition of stone materials of several local historic buildings with a purpose of elaboration of restoration strategy, including the choice of restoration materials. Most of the examined mortars are lime- based hydraulic mortars, characteristic of the architecture of 19th/20th century. Pure aerial lime binders show reduced compatibility with historic materials, that is why lime binders with pozzolan additive (cement) are an appropriate choice for restoration. In order to examine the changes of hydraulicity (i.e. the property of binders to harden when exposed to water) of perspective restoration binders, a series of blended lime-cement mixtures were synthesized with growing content of cement (up to 10% by weight). A significant relationship between cement content and hydraulic properties has been shown.

  12. Deadly Throwaways--Plastic Six-Pack Binders and Metal Pull-Tabs Doom Wildlife

    ERIC Educational Resources Information Center

    Ward, Penny

    1975-01-01

    Thousands of creatures are vulnerable to entrapment, entanglement, strangulation, or starvation as a result of plastic six-pack binders and metal pull-tabs. Possible solutions include: recycling, clean-up campaigns, and strong container legislation. (BT)

  13. Binder-free V2O5 cathode for greener rechargeable aluminum battery.

    PubMed

    Wang, Huali; Bai, Ying; Chen, Shi; Luo, Xiangyi; Wu, Chuan; Wu, Feng; Lu, Jun; Amine, Khalil

    2015-01-14

    This letter reports on the investigation of a binder-free cathode material to be used in rechargeable aluminum batteries. This cathode is synthesized by directly depositing V2O5 on a Ni foam current collector. Rechargeable aluminum coin cells fabricated using the as-synthesized binder-free cathode delivered an initial discharge capacity of 239 mAh/g, which is much higher than that of batteries fabricated using a cathode composed of V2O5 nanowires and binder. An obvious discharge voltage plateau appeared at 0.6 V in the discharge curves of the Ni-V2O5 cathode, which is slightly higher than that of the V2O5 nanowire cathodes with common binders. This improvement is attributed to reduced electrochemical polarization.

  14. Hydroxyapatite moldable formulation using natural rubber latex as binder.

    PubMed

    Sailaja, G S; Ramesh, P; Varma, H K

    2007-07-01

    A simple but efficient processing method for shaping intricate bioceramic green bodies has been developed by using natural rubber latex as binder. Different shapes of hydroxyapatite Ca10(PO4)6(OH)2 (HAP) were molded from a composite formulation containing wet precipitated HAP, natural rubber latex (NRL), and a stabilizer. On controlled heat treatment followed by sintering, dense shapes of HAP contours were obtained. The thermal degradation profile of HAP-NRL composites shows that NRL degrades slowly without any abrupt exotherm. The results of energy dispersive X-ray analysis together with inductively coupled plasma (ICP) analysis indicate that the inorganic residue of NRL does not contain any heavy element. The sintered density of the samples increased with increased HAP content in the formulation and percentage shrinkage reduced accordingly. On varying the HAP content in the formulation from 35 to 95 wt %, the compositions with 85, 90, 92, and 95 wt % HAP showed better flexural strength in the range 40-54 MPa and a flexural modulus value in the range 36-50 GPa. The fracture morphology, as observed by the scanning electron microscope confirms that with increased HAP content in the formulation the sample microstructure attains higher uniformity. The Vickers microhardness for the samples sintered at two different temperatures (1150 and 1250 degrees C) showed that hardness increases with increase in the sintering temperature with a maximum for the highest HAP loaded formulation.

  15. Phase relationships involving RDX and common solid propellant binders

    SciTech Connect

    Boyer, E.; Brown, P.W.; Kuo, K.K.

    1996-07-01

    The solubilities of the common propellant ingredients acetyl triethyl citrate (ATEC) and cellulose acetate butyrate (CAB) and their effects on RDX (cyclotrimethylenetrinitramine) unit cell dimensions were investigated. If there is appreciable solid solubility, solutions will form and will have enthalpies of fusion, melting temperatures, and other characteristics different from those of pure RDX. It is desirable to establish the properties of such mixtures when designing new propellant formulations. Samples were aged at an elevated temperature to speed the formation of solid solutions. A least-squares analysis of X-ray diffraction data was used to obtain the lattice parameters from which unit cell volume and solubility was deduced. Both ATEC and CAB caused an expansion of the unit cell, indicating the formation of a solid solution. The limit of solubility in the ATEC/RDX mixture appeared to be approximately 13 wt% ATEC, while the CAB/RDX limit is above 16 wt% CAB. In both mixes, the cell volume expanded linearly with increasing proportion of binder. The large amount of gas generated and high energy released during combustion make RDX very attractive for both rocket and gun propulsion applications. The absence of HCl in the combustion products makes RDX desirable on an environmental basis as well.

  16. Poly(lactic acid) degradable plastics, coatings, and binders

    SciTech Connect

    Bonsignore, P.V.; Coleman, R.D.; Mudde, J.P.

    1992-05-01

    Biochemical processes to derive value from the management of high carbohydrate food wastes, such as potato starch, corn starch, and cheese whey permeate, have typically been limited to the production of either ethanol or methane. Argonne National Laboratory (ANL) believes that lactic acid presents an attractive option for an alternate fermentation end product, especially in light of lactic acids` being a viable candidate for conversion to environmentally safe poly(lactic acid) (PLA) degradable plastics, coatings, and binders. Technology is being developed at ANL to permit a more cost effective route to modified high molecular weight PLA. Preliminary data on the degradation behavior of these modified PLAs shows the retention to the inherent hydrolytic degradability of the PLA modified, however, by introduced compositional variables. A limited study was done on the hydrolytic stability of soluble oligomers of poly(L-lactic acid). Over a 34 day hold period, water-methanol solutions of Pl-LA oligomers in the 2-10 DP range retained some 75% of their original molecular weight.

  17. Poly(lactic acid) degradable plastics, coatings, and binders

    SciTech Connect

    Bonsignore, P.V.; Coleman, R.D.; Mudde, J.P.

    1992-01-01

    Biochemical processes to derive value from the management of high carbohydrate food wastes, such as potato starch, corn starch, and cheese whey permeate, have typically been limited to the production of either ethanol or methane. Argonne National Laboratory (ANL) believes that lactic acid presents an attractive option for an alternate fermentation end product, especially in light of lactic acids' being a viable candidate for conversion to environmentally safe poly(lactic acid) (PLA) degradable plastics, coatings, and binders. Technology is being developed at ANL to permit a more cost effective route to modified high molecular weight PLA. Preliminary data on the degradation behavior of these modified PLAs shows the retention to the inherent hydrolytic degradability of the PLA modified, however, by introduced compositional variables. A limited study was done on the hydrolytic stability of soluble oligomers of poly(L-lactic acid). Over a 34 day hold period, water-methanol solutions of Pl-LA oligomers in the 2-10 DP range retained some 75% of their original molecular weight.

  18. Asphalt volcanoes as a potential source of methane to late Pleistocene coastal waters

    NASA Astrophysics Data System (ADS)

    Valentine, David L.; Reddy, Christopher M.; Farwell, Christopher; Hill, Tessa M.; Pizarro, Oscar; Yoerger, Dana R.; Camilli, Richard; Nelson, Robert K.; Peacock, Emily E.; Bagby, Sarah C.; Clarke, Brian A.; Roman, Christopher N.; Soloway, Morgan

    2010-05-01

    Every year, natural petroleum seepage emits 0.2-2Tg of oil to the ocean. Significant oil seepage can build large underwater mounds, consisting of tar deposits with morphologies similar to volcanic lava flows, known as asphalt volcanoes. Such events are typically accompanied by large fluxes of the greenhouse gas methane. Marine sediments from the Santa Barbara basin, California, contain a record of elevated methane concentrations, anoxia and tar deposition during the Pleistocene epoch that had been attributed to dissolution of methane hydrates. However, the region is known to have exhibited oil seepage in the past. Here, we document the discovery of seven extinct asphalt volcanoes off the coast of southern California. The morphology of the deposits and geochemistry of samples taken from the two largest structures supports their classification as asphalt volcanoes, derived from a common source. We estimate that the two structures resulted from seepage of 0.07-0.4Tg of oil, accompanied by the emission of 0.35-1.8Tg of methane. Radiocarbon dating of carbonate deposits entrained with the asphalt indicates formation of the volcanoes between 44 and 31kyr ago. The timing and volume of erupted hydrocarbons from the asphalt structures can explain some or all of the documented methane release and tar accumulation in the Santa Barbara basin during the Pleistocene.

  19. Evaluation of the treatment of chromite ore processing residue by ferrous sulfate and asphalt.

    PubMed

    Moon, Deok Hyun; Wazne, Mahmoud; Koutsospyros, Agamemnon; Christodoulatos, Christos; Gevgilili, Halil; Malik, Moinuddin; Kalyon, Dilhan M

    2009-07-15

    The effectiveness of the treatment of chromite ore processing residue (COPR) with ferrous sulfate and encapsulation into asphalt were explored separately and in combination. The asphalt treatment was conducted by mixing COPR or ferrous sulfate pretreated COPR with varying amounts of asphalt. To assess the efficacy of the treatment, the leachability of toxicity characteristic leaching procedure (TCLP) total chromium (Cr) from all treated samples was determined for curing periods up to 16 months. X-ray absorption near edge structure (XANES) analyses were also performed to evaluate the Cr(6+) concentration in the selected samples. The combination treatment of ferrous sulfate and the encapsulation of the treated COPR into asphalt reduced the TCLP total Cr concentration to lower than the regulatory limit of 5mg/L for Cr contaminated soils, after 16 months. However, the Cr concentrations were still higher than the universal treatment standards (UTS) of 0.6 mg/L for hazardous waste. On the other hand, treatment with ferrous sulfate alone or the encapsulation of the COPR in asphalt failed to meet the TCLP total Cr concentration of 5mg/L, after 16 months. XANES analyses results showed that more than 75% Cr(6+) reduction was achieved upon pretreatment with ferrous sulfate.

  20. A review of air quality issues and compliance for the asphalt paving industry in Maryland

    SciTech Connect

    Courtright, B.F.; Caughlin, M.J.

    1999-07-01

    The Maryland Air and Radiation Management Administration (ARMA) conducted a Sector Initiative in order to achieve a compliance audit of the asphalt paving industry sector in Maryland. This sector is commonly referred to as the hot-mix asphalt (HMA) industry. There are 59 HMA production plants in Maryland. Each asphalt production facility was reviewed to determine their compliance status with federal NSPS requirements (stack particulate and visible emission requirements), as well as with Maryland's more comprehensive and generally more restrictive requirements including visible emission, particulate matter, air toxics, dust, nuisance, odor, and other criteria pollutant requirements. The study included reviewing past data (stack test reports, inspections, VE observations, complaint histories) and conducting new inspections and observations at all 59 of the plants. The study also included conducting new particulate stack tests (Summer of 1998) at nine HMA plants. The historic data demonstrated general compliance with stack-tested particulate emission rates. The new stack tests all demonstrated compliance with applicable particulate limits. Visible emissions observations revealed a lesser degree of compliance. Asphalt plants, if not carefully controlled, can be a major source of nuisance complaints. Complaint histories were also reviewed. This paper presents detailed results of ARMA's compliance review of the asphalt industry in Maryland. This includes test results, compliance determinations, and compliance rates. Other issues including impacts on surrounding communities, changing Department of Transportation requirements, and air toxics requirements are also reviewed.

  1. A feasibility study to use coal tar contaminated soil in asphalt cement mixture production

    SciTech Connect

    Dulam, C.S.; Hoag, G.E.; Dahmani, A.; Nadim, F.

    1996-11-01

    Coal tars are the residues produced during the gasification of coal. Traditionally, coal tars were buried onsite at the power plants or left as residuals in the bottom of gas holders. Currently, there are more than 1,500 such historic sites which will undergo site assessment in the near future. The use of coal tar residuals in asphalt-based products could result in greatly reduced disposal costs, in comparison to current methods of disposal. Present disposal practice of coal tar contaminated residuals includes disposal in hazardous waste landfills or incineration. Treatment and disposal costs are reported to be as much as $1,000/ton for current coal tar contaminated residuals disposal options. This feasibility study was performed to determine the use of coal tar contaminated soil (CTCS) in bituminous materials to produce hot asphalt mix. Mixtures of varying composition of CTCS and bituminous material were produced to perform TCLP. The air emissions during the mixing process were captured and analyzed. In this study, a bench scale investigation was performed to identify and quantify the emissions from heating the CTCS at the mixer temperature. The pilot scale investigations were performed by replacing reclaimable asphalt pavement (RAP) with CTCS during the hot asphalt mix production. The investigations were performed on two types of mixtures; using CTCS as the direct additive in the first type, and using SS-1 (slow setting asphalt emulsion) stabilized CTCS as an additive in the second type.

  2. The effects of salt on rheological properties of asphalt after long-term aging.

    PubMed

    Yu, Xin; Wang, Ying; Luo, Yilin; Yin, Long

    2013-01-01

    Limited studies in recent years have shown that asphalt pavement subject to seawater in coastal regions or deicing salt in cold regions may be seriously damaged after being soaked in saline water for a long time. However, there is limited research into the influence of salt on rheological properties of asphalt after long-term aging. In this study, rheological properties of unmodified and polymer-modified asphalt after long-term aging were tested after being soaked in different concentrations of salt (0.3%~5%) for different durations (1 day~30 days). Orthogonal array based on the Taguchi method was used for experimental design. The frequency sweep tests were performed on the specimens of aged asphalt after being soaked for complex modulus and phase angle master curves and ultimate fatigue temperature. BBR tests were performed for stiffness. The test results indicate that saline water appears to reduce low temperature properties and fatigue resistance properties and improved high temperature properties of aged asphalt, and it also affects the sensitivity of complex modulus and phase angles at low frequencies.

  3. Evaluation of an eastern shale oil residue as an asphalt additive

    SciTech Connect

    Thomas, K.P.; Harnsberger, P.M.

    1995-12-19

    An evaluation of eastern shale oil (ESO) residue as an asphalt additive to reduce oxidative age-hardening and moisture susceptibility was conducted. The ESO residue, having a viscosity of 23.9 Pa{sm_bullet}s at 60{degrees}C (140{degrees}F), was blended with three different petroleum-derived asphalts, AAD-1, AAK-1, and AAM-1, that are known to be very susceptible to oxidative aging. Rheological and infrared analyses of the unaged and aged asphalts and the blends were then conducted to evaluate oxidative age-hardening. In addition, the petroleum-derived asphalts and the blends were coated onto three different aggregates, Lithonia granite (RA), a low-absorption limestone (RD), and a silicious Gulf Coast gravel (RL), and compacted into briquets. Successive freeze-thaw cycling was then conducted to evaluate the moisture susceptibility of the prepared briquets. The abbreviations used above for the asphalts and the aggregates are part of the Strategic Highway Research Program nomenclature.

  4. The Effects of Salt on Rheological Properties of Asphalt after Long-Term Aging

    PubMed Central

    Yu, Xin; Luo, Yilin; Yin, Long

    2013-01-01

    Limited studies in recent years have shown that asphalt pavement subject to seawater in coastal regions or deicing salt in cold regions may be seriously damaged after being soaked in saline water for a long time. However, there is limited research into the influence of salt on rheological properties of asphalt after long-term aging. In this study, rheological properties of unmodified and polymer-modified asphalt after long-term aging were tested after being soaked in different concentrations of salt (0.3%~5%) for different durations (1 day~30 days). Orthogonal array based on the Taguchi method was used for experimental design. The frequency sweep tests were performed on the specimens of aged asphalt after being soaked for complex modulus and phase angle master curves and ultimate fatigue temperature. BBR tests were performed for stiffness. The test results indicate that saline water appears to reduce low temperature properties and fatigue resistance properties and improved high temperature properties of aged asphalt, and it also affects the sensitivity of complex modulus and phase angles at low frequencies. PMID:24459450

  5. Solar-reflective coating as a cooling overlay for asphalt pavement

    NASA Astrophysics Data System (ADS)

    Wang, He; Xu, Geng; Feng, Decheng; Zhong, Jing; Xie, Ning

    2011-11-01

    Rutting is one of the most serious problems on asphalt pavements. Decrease the surface temperature of the asphalt pavement is an effective method to solve the rutting problem on asphalt pavements. In this study, nano sized particles filled polymer composite was developed as an overlay to reflect the solar energy and decrease the surface temperature of asphalt pavements. The overlay was composed of acrylic or epoxy resin filled with nano TiO2 or nano TiNO2. The solar reflection of the nano particle filled polymers was tested and the results showed that solar reflection effectiveness of the epoxy/TiO2 composite reached the highest value. The results of outdoor temperature test indicate that the solar-reflective overlay could decrease the surface temperature of asphalt pavements about 10 °C when the pavement temperature is about 60 °C. Pavement skid resistance was also tested, which expressed by micro/macrotexture depth and the results of which showed that both matrix was qualified after coated with aggregates on the surface.

  6. Solar-reflective coating as a cooling overlay for asphalt pavement

    NASA Astrophysics Data System (ADS)

    Wang, He; Xu, Geng; Feng, Decheng; Zhong, Jing; Xie, Ning

    2012-04-01

    Rutting is one of the most serious problems on asphalt pavements. Decrease the surface temperature of the asphalt pavement is an effective method to solve the rutting problem on asphalt pavements. In this study, nano sized particles filled polymer composite was developed as an overlay to reflect the solar energy and decrease the surface temperature of asphalt pavements. The overlay was composed of acrylic or epoxy resin filled with nano TiO2 or nano TiNO2. The solar reflection of the nano particle filled polymers was tested and the results showed that solar reflection effectiveness of the epoxy/TiO2 composite reached the highest value. The results of outdoor temperature test indicate that the solar-reflective overlay could decrease the surface temperature of asphalt pavements about 10 °C when the pavement temperature is about 60 °C. Pavement skid resistance was also tested, which expressed by micro/macrotexture depth and the results of which showed that both matrix was qualified after coated with aggregates on the surface.

  7. 77 FR 50651 - Approval and Promulgation of Air Quality Implementation Plans; New Hampshire; Hot Mix Asphalt Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-22

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; New Hampshire; Hot... Hampshire Hot Mix Asphalt Plant Rule at Env-A 2703.02(a). This rule establishes and requires limitations on visible emissions from all hot mix asphalt plants. This revision is consistent with the maintenance of...

  8. Characterization of hydrocarbon emissions from green sand foundry core binders by analytical pyrolysis

    SciTech Connect

    Yujue Wang; Fred S. Cannon; Magda Salama; Jeff Goudzwaard; James C. Furness

    2007-11-15

    Analytical pyrolysis was conducted to compare the hydrocarbon and greenhouse gas emissions of three foundry sand binders: (a) conventional phenolic urethane resin, (b) biodiesel phenolic urethane resin, and (c) collagen-based binder. These binders are used in the metal casting industry to create internal cavities within castings. Green sand contains silica sand, clay, carbonaceous additives (eg bituminous coal) and water. The core samples were flash pyrolyzed in a Curie-point pyrolyzer at 920{sup o}C with a heating rate of about 3000{sup o}C/sec. This simulated some key features of the fast heating conditions that the core binders would experience at the metal-core interface when molten metal is poured into green sand molds. The core samples were also pyrolyzed in a thermogravimetric analyzer (TGA) from ambient temperature to 1000{sup o}C with a heating rate of 30{sup o}C/min, and this simulated key features of the slow heating conditions that the core binders would experience at distances that are further away from the metal-core interface during casting cooling. Hydrocarbon emissions from flash pyrolysis were analyzed with a gas chromatography-flame ionization detector, while hydrocarbon and greenhouse gas emissions from TGA pyrolysis were monitored with mass spectrometry. The prominent hazardous air pollutant emissions during pyrolysis of the three binders were phenol, cresols, benzene, and toluene for the conventional phenolic urethane resin and biodiesel resin, and benzene and toluene for the collagen-based binder. Bench-scale analytical pyrolysis techniques could be a useful screening tool for the foundries to compare the relative emissions of alternative core binders and to choose proper materials in order to comply with air-emission regulations. 20 refs., 4 figs., 1 tab.

  9. Chelating effect in short polymers for the design of bidentate binders of increased affinity and selectivity

    NASA Astrophysics Data System (ADS)

    Fortuna, Sara; Fogolari, Federico; Scoles, Giacinto

    2015-10-01

    The design of new strong and selective binders is a key step towards the development of new sensing devices and effective drugs. Both affinity and selectivity can be increased through chelation and here we theoretically explore the possibility of coupling two binders through a flexible linker. We prove the enhanced ability of double binders of keeping their target with a simple model where a polymer composed by hard spheres interacts with a spherical macromolecule, such as a protein, through two sticky spots. By Monte Carlo simulations and thermodynamic integration we show the chelating effect to hold for coupling polymers whose radius of gyration is comparable to size of the chelated particle. We show the binding free energy of flexible double binders to be higher than that of two single binders and to be maximized when the binding sites are at distances comparable to the mean free polymer end-to-end distance. The affinity of two coupled binders is therefore predicted to increase non linearly and in turn, by targeting two non-equivalent binding sites, this will lead to higher selectivity.

  10. Chelating effect in short polymers for the design of bidentate binders of increased affinity and selectivity

    PubMed Central

    Fortuna, Sara; Fogolari, Federico; Scoles, Giacinto

    2015-01-01

    The design of new strong and selective binders is a key step towards the development of new sensing devices and effective drugs. Both affinity and selectivity can be increased through chelation and here we theoretically explore the possibility of coupling two binders through a flexible linker. We prove the enhanced ability of double binders of keeping their target with a simple model where a polymer composed by hard spheres interacts with a spherical macromolecule, such as a protein, through two sticky spots. By Monte Carlo simulations and thermodynamic integration we show the chelating effect to hold for coupling polymers whose radius of gyration is comparable to size of the chelated particle. We show the binding free energy of flexible double binders to be higher than that of two single binders and to be maximized when the binding sites are at distances comparable to the mean free polymer end-to-end distance. The affinity of two coupled binders is therefore predicted to increase non linearly and in turn, by targeting two non-equivalent binding sites, this will lead to higher selectivity. PMID:26496975

  11. Investigation of film solidification and binder migration during drying of Li-Ion battery anodes

    NASA Astrophysics Data System (ADS)

    Jaiser, Stefan; Müller, Marcus; Baunach, Michael; Bauer, Werner; Scharfer, Philip; Schabel, Wilhelm

    2016-06-01

    The property determining micro-structure of battery electrodes essentially evolves during drying, appointing it a paramount, yet insufficiently understood processing step in cell manufacturing. The distribution of functional additives such as binder or carbon black throughout the film strongly depends on the drying process. A representative state-of-the-art model system comprising graphite, polymeric binder, carbon black and solvent is investigated to gain an insight into the underlying processes. A new experimental approach is introduced that allows for revelation of the evolution of binder concentration gradients throughout the film during drying. Binder is detected by means of energy-dispersive x-ray spectroscopy (EDS) at the top and bottom surface. Drying kinetics is investigated and the impact of the drying process on electrochemical performance is disclosed. The enrichment of binder at the surface, which is observed while applying high drying rates, is shown to depend on two fundamental processes, namely capillary action and diffusion. The findings reveal characteristic drying stages that provide fundamental insights into film solidification. Based on that, a top-down consolidation mechanism capable of explaining the experimental findings is disclosed. Adhesion of the active layer to the substrate is shown to strongly depend on the local binder concentration in the vicinity of the substrate.

  12. Comparisons of operating envelopes for contaminated soil stabilised/solidified with different cementitious binders.

    PubMed

    Kogbara, Reginald B; Al-Tabbaa, Abir; Stegemann, Julia A

    2014-03-01

    This work initiated the development of operating envelopes for stabilised/solidified contaminated soils. The operating envelopes define the range of operating variables for acceptable performance of the treated soils. The study employed a soil spiked with 3,000 mg/kg each of Cd, Cu, Pb, Ni and Zn, and 10,000 mg/kg of diesel. The binders used for treatment involved Portland cement (CEMI), pulverised fuel ash (PFA), ground granulated blast furnace slag (GGBS) and hydrated lime (hlime). The specific binder formulations were CEMI, CEMI/PFA = 1:4, CEMI/GGBS = 1:9 and hlime/GGBS = 1:4. The water contents employed ranged from 13 % to 21 % (dry weight), while binder dosages ranged from 5 % to 20 % (w/w). We monitored the stabilised/solidified soils for up to 84 days using different performance tests. The tests include unconfined compressive strength (UCS), hydraulic conductivity, acid neutralisation capacity (ANC) and pH-dependent leachability of contaminants. The water content range resulted in adequate workability of the mixes but had no significant effect on leachability of contaminants. We produced design charts, representing operating envelopes, from the results generated. The charts establish relationships between water content, binder dosage and UCS; and binder dosage, leachant pH and leachability of contaminants. The work also highlights the strengths and weaknesses of the different binder formulations. PMID:24243092

  13. Phosphate Binders and Clinical Outcomes in Patients with Stage 5D Chronic Kidney Disease.

    PubMed

    Zoccali, Carmine; Mallamaci, Francesca; Cannata-Andía, Jorge

    2015-01-01

    Knowledge informing the prescription and the choice of phosphate binders in end stage kidney disease (ESKD) patients has a weak evidentiary base. To date, no placebo-controlled trial based on meaningful clinical endpoints (death, cardiovascular events, bone fractures) has been performed to test the efficacy of these drugs. By the same token, we still lack solid proof that noncalcium binders afford better clinical outcomes as compared with calcium-based binders. Without proper trials, clinical decisions about the treatment of hyperphosphatemia rest on experience and contingent clinical judgment. The use of huge doses of calcium-based binders typically prescribed in the nineties now appears unwarranted. The relationship between phosphate and the risk of death is U shaped and moderate hyperphosphatemia carries just a mild-to-moderate risk excess and may not be seen as a compelling indication for the prescription of phosphate binders. Placebo-controlled randomized clinical trials assessing whether non-calcium and calcium-based binders reduce the risk of death and cardiovascular disease events in ESKD patients remain a public health priority. PMID:26278591

  14. Experimentally validated computational modeling of organic binder burnout from green ceramic compacts

    SciTech Connect

    Ewsuk, K.G.; Cochran, R.J.; Blackwell, B.F.; Cesarano, J.; Adkins, D.R.

    1995-09-01

    The properties and performance of a ceramic component is determined by a combination of the materials from which it was fabricated and how it was processed. Most ceramic components are manufactured by dry pressing a powder/binder system in which the organic binder provides formability and green compact strength. A key step in this manufacturing process is the removal of the binder from the powder compact after pressing. The organic binder is typically removed by a thermal decomposition process in which heating rate, temperature, and time are the key process parameters. Empirical approaches are generally used to design the burnout time-temperature cycle, often resulting in excessive processing times and energy usage, and higher overall manufacturing costs. Ideally, binder burnout should be completed as quickly as possible without damaging the compact, while using a minimum of energy. Process and computational modeling offer one means to achieve this end. The objective of this study is to develop an experimentally validated computer model that can be used to better understand, control, and optimize binder burnout from green ceramic compacts.

  15. Development of a rapid test method for asphalt concrete content determination in hot-mix paving mixtures

    NASA Astrophysics Data System (ADS)

    Chavez, J. J. M.

    1984-01-01

    A rapid test method was developed for the determination of asphalt cement content in hot-mix bituminous paving mixtures. It is based on the extraction of asphalt cement from mixtures with trichloroethylene and subsequent measurement of the transmittance of light through the extracted solution. A good correlation was found between the results obtained using the rapid test and those obtained using the standard test (ASTM D-2172, Method E1) for samples tested in the field at asphalt mix plants. The test uses a portable spectrophotometer and a metal can for extraction. The asphalt content can be determined in less than ten minutes. The possibility of using the rapid test on materials containing emulsified asphalt, slag aggregate, unusually high amounts of fine material and recycled material was also studied.

  16. The shakeout scenario: Meeting the needs for construction aggregates, asphalt, and concrete

    USGS Publications Warehouse

    Langer, W.H.

    2011-01-01

    An Mw 7.8 earthquake as described in the ShakeOut Scenario would cause significantdamage to buildings and infrastructure. Over 6 million tons of newly mined aggregate would be used for emergency repairs and for reconstruction in the five years following the event. This aggregate would be applied mostly in the form of concrete for buildings and bridges, asphalt or concrete for pavement, and unbound gravel for applications such as base course that goes under highway pavement and backfilling for foundations and pipelines. There are over 450 aggregate, concrete, and asphalt plants in the affected area, some of which would be heavily damaged. Meeting the increased demand for construction materials would require readily available permitted reserves, functioning production facilities, a supply of cement and asphalt, a source of water, gas, and electricity, and a trained workforce. Prudent advance preparations would facilitate a timely emergency response and reconstruction following such an earthquake. ?? 2011, Earthquake Engineering Research Institute.

  17. Co-firing of asphalt fired dust in pulverized coal fired boiler

    SciTech Connect

    Kiga, Takashi; Watanabe, Shinjl

    1999-07-01

    In order to make clear whether the dust collected at the electrostatic precipitator (EP) of asphalt fired boilers can be co-fired in pulverized coal fired boilers, laboratory-scale and bench-scale tests have been conducted. Test results showed that although dust from asphalt firing had as only a little amount of volatile matter as semi-anthracite or anthracite had, it revealed burn-out properties like bituminous. When it was co-fired with pulverized coal by 2% by that input, a considerable increase in SO{sub 2} emission was noted, while NOx emission was somewhat decreased compared with coal firing. From these verifications, it was confirmed that the co-firing of dust from asphalt firing in pulverized coal fired boiler was applicable to actual plants so far as the De-SOx system permitted.

  18. Analysis of ground reflection of jet noise obtained with various microphone arrays over an asphalt surface

    NASA Technical Reports Server (NTRS)

    Miles, J. H.

    1975-01-01

    Ground reflection effects on the propagation of jet noise over an asphalt surface are discussed for data obtained using a 33.02-cm diameter nozzle with microphones at several heights and distances from the nozzle axis. Ground reflection effects are analyzed using the concept of a reflected signal transfer function which represents the influence of both the reflecting surface and the atmosphere on the propagation of the reflected signal in a mathematical model. The mathematical model used as a basis for the computer program was successful in significantly reducing the ground reflection effects. The range of values of the single complex number used to define the reflected signal transfer function was larger than expected when determined only by the asphalt surface. This may indicate that the atmosphere is affecting the propagation of the reflected signal more than the asphalt surface. The selective placement of the reinforcements and cancellations in the design of an experiment to minimize ground reflection effects is also discussed.

  19. Use of asphalt emulsion sealants in disposal of uranium mill tailings

    SciTech Connect

    Hartley, J.N.; Freeman, H.D.; Elmore, M.R.

    1981-07-01

    Studies of asphalt emulsion sealants conducted by the Pacific Northwest Laboratory have demonstrated that the sealants are effective in containing radon within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to near background levels. Field tests at the tailings pile in Grand Junction, Colorado confirmed that an 8-cm admix seal containing 22 wt % asphalt could be effectively applied with a cold-mix paver. Other techniques were successfully tested, including a soil stabilizer and a hot, rubberized asphalt seal that was applied with a distributor truck. After the seals were applied and compacted, overburden was applied over the seal to protect the seal from ultraviolet degradation.

  20. Recycled tire rubber and other waste materials in asphalt mixtures. Transportation research record

    SciTech Connect

    1995-12-31

    The papers in this volume, dealing with various facets of recycled tire rubber and other waste materials in asphalt mixtures, should be of interest to state and local construction, design, materials, and research engineers as well as contractors and material producers. In the first papers, Rebala and Estakhri, Malpass and Khosla, and Baker and Connolly describe research related to crumb rubber modified mixtures that was done for the Texas, North Carolina, and New Jersey State Departments of Transportation. Ali et al. report on their research in Canada to determine the feasibility of sing reclaimed roofing materials in hot mix asphalt pavement. Emery discusses the evaluation of 11 Ontario rubber modified demonstration projects in terms of pavement performance, environmental impacts, and recyclability. In the last paper, Fwa and Aziz report on their work in Singapore related to the use of incinerator residue in asphalt mixtures.

  1. Application of pyrolized carbon black from scrap tires in asphalt pavement design and construction

    SciTech Connect

    Park, T.; Coree, B.J.; Lovell, C.W.

    1995-12-31

    According to EPA reports (1991) of the over 242 million waste generated each year in the United State, 5% are exported, 6% recycled, 11% incinerated, and 78% are landfilled, stockpiled, or illegally dumped. A variety of uses for these tires are being studied. Among these is pyrolysis which produces 5 5% of oil, 25% of carbon black, 9% of steel, 5% of fiber and 6% of gas. Pyrolized carbon black contains 9 % of ash, 4% of sulfur, 12% of butadine copolymer and 75% of carbon black. The objective of this research is to investigate the viability of using PCB as an additive in hot mix asphalt. The use of PCB in asphalt pavement is expected not only to improve the performance of conventional asphalt, but also to provide a means for the mass disposal of waste fires.

  2. Physical and chemical characteristics of synthetic asphalt produced from liquefaction of sewage sludge

    NASA Astrophysics Data System (ADS)

    Donovan, J. M.; Batter, T. R.; Miller, R. K.; Lottman, R. P.

    1981-10-01

    Direct thermochemical liquefaction of primary undigested municipal sewage sludge was carried out to produce a low molecular weight steam volatile oil, a high molecular weight synthetic asphalt, and a residual char cake. The latter product is capable of supplying the thermal energy requirements of the conversion process. The steam volatile oil has immediate value as a synthetic fuel oil. The synthetic asphalt may prove to be a useful cement for paving or for fuel or coking stock. The thermochemical liquefaction process should be capable of operating technically and in an environmentally acceptable manner in conjunction with many existing waste water treatment facilities. The overall feasibility of the process depends on the value of the oil and synthetic asphalt products as petroleum replacements, and on the costs associated with disposal of sludge.

  3. Asphalt emulsion radon barrier systems for uranium mill tailings: an overview of the technology

    SciTech Connect

    Baker, E.G.; Hartley, J.N.; Freeman, H.D.; Gates, T.E.; Nelson, D.A.; Dunning, R.L.

    1984-03-01

    Pacific Northwest Laboratory (PNL), under contract to the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) office, has developed an asphalt emulsion cover system to reduce the release of radon from uranium mill tailings. The system has been field tested at Grand Junction, Colorado. Results from laboratory and field tests indicate that this system is effective in reducing radon release to near-background levels (<2.5 pCi m/sup -2/s/sup -1/) and has the properties required for long-term effectiveness and stability. Engineering specifications have been developed, and analysis indicates that asphalt emulsion covers are cost-competitive with other cover systems. This report summarizes the technology for asphalt emulsion radon barrier systems. 59 references, 45 figures, 36 tables.

  4. On the study of crack-initiation fracture toughness of fiber glass asphalt shingles

    SciTech Connect

    Shiao, M.L.

    1999-07-01

    The fracture behavior of fiber glass asphalt shingles was examined by measuring their J-integral fracture toughness at crack initiation. The corresponding fracture mechanisms were also studied by in situ fracture observation and by scanning electron microscopy. The applicability of using J-integral fracture toughness to characterize asphalt shingles was discussed and its relationships to other mechanical properties was established. The results indicated that the fracture toughness at crack initiation can be accurately measured for fiber glass shingles and the values may be used to characterize their cracking resistance. Fracture toughness measured from various shingle samples was found to correlate to the shingle's tensile toughness and to its tear strength. Preliminary results on fracture mechanisms suggested that failure in the asphalt coatings by micro-cavitation may be the controlling event leading to crack advance. The importance of the glass fiber mat on a shingle's resistance to fracture was also discussed.

  5. Early-age hydration and volume change of calcium sulfoaluminate cement-based binders

    NASA Astrophysics Data System (ADS)

    Chaunsali, Piyush

    Shrinkage cracking is a predominant deterioration mechanism in structures with high surface-to-volume ratio. One way to allay shrinkage-induced stresses is to use calcium sulfoaluminate (CSA) cement whose early-age expansion in restrained condition induces compressive stress that can be utilized to counter the tensile stresses due to shrinkage. In addition to enhancing the resistance against shrinkage cracking, CSA cement also has lower carbon footprint than that of Portland cement. This dissertation aims at improving the understanding of early-age volume change of CSA cement-based binders. For the first time, interaction between mineral admixtures (Class F fly ash, Class C fly ash, and silica fume) and OPC-CSA binder was studied. Various physico-chemical factors such as the hydration of ye'elimite (main component in CSA cement), amount of ettringite (the main phase responsible for expansion in CSA cement), supersaturation with respect to ettringite in cement pore solution, total pore volume, and material stiffness were monitored to examine early-age expansion characteristics. This research validated the crystallization stress theory by showing the presence of higher supersaturation level of ettringite, and therefore, higher crystallization stress in CSA cement-based binders. Supersaturation with respect to ettringite was found to increase with CSA dosage and external supply of gypsum. Mineral admixtures (MA) altered the expansion characteristics in OPC-CSA-MA binders with fixed CSA cement. This study reports that fly ash (FA) behaves differently depending on its phase composition. The Class C FA-based binder (OPC-CSA-CFA) ceased expanding beyond two days unlike other OPC-CSA-MA binders. Three factors were found to govern expansion of CSA cement-based binders: 1) volume fraction of ettringite in given pore volume, 2) saturation level of ettringite, and 3) dynamic modulus. Various models were utilized to estimate the macroscopic tensile stress in CSA cement

  6. Chemical and mutagenic properties of asphalt fume condensates generated under laboratory and field conditions.

    PubMed

    Reinke, G; Swanson, M; Paustenbach, D; Beach, J

    2000-08-21

    Exposure to asphalt fumes is widely recognized as a potential occupational health concern for paving and roofing workers. Two studies suggest that asphalt fumes generated in the laboratory are carcinogenic to mice. In this study, asphalt fume condensate (AFC) was collected from the head space of an operating hot mix asphalt storage tank and from a laboratory fume-generating apparatus operating at approximately 149 degrees C and 316 degrees C. Salmonella assays for mutagenesis, in vitro chromosomal aberration assays using Chinese hamster ovary (CHO) cells, chemical analyses, and simulated distillations were performed using gas chromatography to characterize the toxicological and chemical properties of AFCs generated by these two methods. The 316 degrees C lab AFC sample was more mutagenic in the Salmonella assay than the 149 degrees C lab AFC sample, with mutagenicity indices (MIs) of 8.3 and 5.3, respectively. AFCs collected from the storage tank were not mutagenic. Chromosomal aberration assays of all AFCs were negative. Chemical analyses and simulated distillations showed substantial differences in the chemical composition of the AFC samples. The 316 degrees C lab AFC sample contained more higher-boiling-point (three- and four-ring) polycyclic aromatic sulfur heterocycle compounds than the 149 degrees C lab AFC sample, and both lab AFC samples contained 5 to 100 times more of these compounds than AFC samples collected from the asphalt storage tank. These results are consistent with other data reported in the scientific literature describing the carcinogenicity of higher-boiling-point sulfur heterocycle compounds. In contrast to other recent studies, the results of this study indicate that the chemical composition and toxicological properties of laboratory-generated asphalt fumes are not representative of those properties of fumes to which workers and the public might be exposed. PMID:10946241

  7. Novel, inorganic composites using porous, alkali-activated, aluminosilicate binders

    NASA Astrophysics Data System (ADS)

    Musil, Sean

    Geopolymers are an inorganic polymeric material composed of alumina, silica, and alkali metal oxides. Geopolymers are chemical and fire resistant, can be used as refractory adhesives, and are processed at or near ambient temperature. These properties make geopolymer an attractive choice as a matrix material for elevated temperature composites. This body of research investigated numerous different reinforcement possibilities and variants of geopolymer matrix material and characterized their mechanical performance in tension, flexure and flexural creep. Reinforcements can then be chosen based on the resulting properties to tailor the geopolymer matrix composites to a specific application condition. Geopolymer matrix composites combine the ease of processing of polymer matrix composites with the high temperature capability of ceramic matrix composites. This study incorporated particulate, unidirectional fiber and woven fiber reinforcements. Sodium, potassium, and cesium based geopolymer matrices were evaluated with cesium based geopolymer showing great promise as a high temperature matrix material. It showed the best strength retention at elevated temperature, as well as a very low coefficient of thermal expansion when crystallized into pollucite. These qualities made cesium geopolymer the best choice for creep resistant applications. Cesium geopolymer binders were combined with unidirectional continuous polycrystalline mullite fibers (Nextel(TM) 720) and single crystal mullite fibers, then the matrix was crystallized to form cubic pollucite. Single crystal mullite fibers were obtained by the internal crystallization method and show excellent creep resistance up to 1400°C. High temperature flexural strength and flexural creep resistance of pollucite and polycrystalline/single-crystal fibers was evaluated at 1000-1400°C.

  8. Evaluation of recycled hot-mix asphaltic concrete in Pennsylvania. Final report, Mar 83-Feb 91

    SciTech Connect

    Beam, J.L.; Maurer, D.

    1991-02-01

    The report includes a construction overview and analyzes the benefits of recycling hot mix asphaltic concrete. The Department has been working with hot mix recycling since 1981 with good results. Since 1985, it has been the Department policy to allow hot mix recycling as an alternative on all hot mix paving contracts. Hot mix recycling conserves natural resources of petroleum products and virgin aggregates. The conservation of resources can result in monetary savings as well. The Department should continue to promote and encourage more extensive use of hot mix asphalt concrete recycling through specification revisions, policy letters and directives. Proposed revisions to Section 403 of the 408 Specifications are provided.

  9. Emission of organic compounds from mould and core binders used for casting iron, aluminium and bronze in sand moulds.

    PubMed

    Tiedje, Niels; Crepaz, Rudolf; Eggert, Torben; Bey, Niki

    2010-12-01

    Emissions from mould and core sand binders commonly used in the foundry industry have been investigated. Degradation of three different types of binders was investigated: Furfuryl alcohol (FA), phenolic urethane (PU) and resol-CO2 (RC). In each group of binders, at least two different binder compositions were tested. A test method that provides uniform test conditions is described. The method can be used as a general test method to analyse off gases from binders. Moulds, containing a standard size casting, were produced and the amount and type of organic compounds, resulting from thermal degradation of binders, was monitored when cast iron, bronze and aluminium was poured in the moulds. Binder degradation was measured by collecting off gases in a specially designed ventilation hood at a constant flow rate. Samples were taken from the ventilation system and analysed for hydrocarbons and CO content. It is shown how off-gases vary with time after pouring and shake out. Also the composition of off-gases is analysed and shown. It is further shown how the composition of off-gasses varies between different types of binders and with varying composition of the binders as well as function of the thermal load on the moulding sand. PMID:20954042

  10. Characterization of hydrocarbon emissions from green sand foundry core binders by analytical pyrolysis.

    PubMed

    Wang, Yujue; Cannon, Fred S; Salama, Magda; Goudzwaard, Jeff; Furness, James C

    2007-11-15

    Analytical pyrolysis was conducted to study a relative comparison of the hydrocarbon and greenhouse gas emissions of three foundry sand binders as follows: (a) conventional phenolic urethane resin, (b) biodiesel phenolic urethane resin, and (c) collagen-based binder. These binders are used in the metal casting industry for making cores that are used to create internal cavities within castings. In this study, the core samples were flash pyrolyzed in a Curie-point pyrolyzer at 920 degrees C with a heating rate of about 3000 degrees C/sec. This simulated some key features of the fast heating conditions that the core binders would experience at the metal-core interface when molten metal is poured into green sand molds. The core samples were also pyrolyzed in a thermogravimetric analyzer (TGA) from ambient temperature to 1000 degrees C with a heating rate of 30 degrees C/min, and this simulated key features of the slow heating conditions that the core binders would experience at distances that are further away from the metal-core interface during casting cooling. Hydrocarbon emissions from flash pyrolysis were analyzed with a gas chromatography-flame ionization detector, while hydrocarbon and greenhouse gas (CO and CO2) emissions from TGA pyrolysis were monitored with mass spectrometry. The prominent hazardous air pollutant emissions during pyrolysis of the three binders were phenol, cresols, benzene, and toluene for the conventional phenolic urethane resin and biodiesel resin, and they were benzene and toluene for the collagen-based binder. It was also found that volatile organic compound and polycyclic aromatic hydrocarbon emissions considerably decreased in order from conventional phenolic urethane resin to biodiesel resin to collagen-based binder. These results have shown some similarity with those for stack emission testing conducted at demonstration scale and/or full-scale foundries, and the similar trends in the two sets of results offered promise that bench

  11. Development of an MgO-based binder for stabilizing fine sediments and storing CO2.

    PubMed

    Hwang, Kyung-Yup; Ahn, Jun-Young; Kim, Cheolyong; Seo, Jeong-Yun; Hwang, Inseong

    2015-12-01

    An MgO-based binder was developed that could stabilize fine dredged sediments for reuse and store CO2. Initially, a binder consisting of fly ash (FA) and blast furnace slag (BFS) was developed by using alkaline activators such as KOH, NaOH, and lime. The FA0.4-BFS0.6 binder (mixed at a FA-to-BFS weight ratio of 4:6) showed the highest compressive strength of 10.7 MPa among FA/BFS binders when 5 M KOH was used. When lime (L) was tested as an alkaline activator, the strength was comparable with those obtained when KOH or NaOH was used. The L0.1-(FA0.4BFS0.6)0.9 binder (10 % lime mixed with the FA/BFS binder) showed the highest strength of 11.0 MPa. Finally, by amending this L0.1-(FA0.4BFS0.6)0.9 binder with MgO, a novel MgO-based binder (MgO0.5-(L0.1-(FA0.4BFS0.6)0.9) 0.5) was developed, which demonstrated the 28th day strength of 11.9 MPa. The MgO-based binder was successfully applied to stabilize a fine sediment to yield a compressive strength of 4.78 MPa in 365 days, which was higher than that obtained by the Portland cement (PC) system (3.22 MPa). Carbon dioxide sequestration was evidenced by three observations: (1) the decrease in pH of the treated sediment from 12.2 to 11.0; (2) the progress of the carbonation front inward the treated sediment; and (3) the presence of magnesium carbonates. The thermogravimetric analysis (TGA) results showed that 67.2 kg of CO2 per ton of the treated sediment could be stored under the atmospheric condition during 1 year. PMID:26224682

  12. Control of binder viscosity and hygroscopicity on particle aggregation efficiency

    NASA Astrophysics Data System (ADS)

    Mueller, Sebastian B.; Kueppers, Ulrich; Ayris, Paul M.; Jacob, Michael; Delmelle, Pierre; Dingwell, Donald B.

    2016-04-01

    In the course of explosive volcanic eruptions, large amounts of ash are released into the atmosphere and may subsequently pose a threat to infrastructure, such as aviation industry. Ash plume forecasting is therefore a crucial tool for volcanic hazard mitigation but may be significantly affected by aggregation, altering the aerodynamic properties of particles. Models struggle with the implementation of aggregation since external conditions promoting aggregation have not been completely understood; in a previous study we have shown the rapid generation of ash aggregates through liquid bonding via the use of fluidization bed technology and further defined humidity and temperature ranges necessary to trigger aggregation. Salt (NaCl) was required for the recovery of stable aggregates, acting as a cementation agent and granting aggregate cohesion. A numerical model was used to explain the physics behind particle aggregation mechanisms and further predicted a dependency of aggregation efficiency on liquid binder viscosity. In this study we proof the effect of viscosity on particle aggregation. HCl and H2SO4 solutions were diluted to various concentrations resulting in viscosities between 1 and 2 mPas. Phonolitic and rhyolitic ash samples as well as soda-lime glass beads (serving as analogue material) were fluidized in the ProCell Lab® of Glatt Ingenieurtechnik GmbH and treated with the acids via a bottom-spray technique. Chemically driven interaction between acid liquids and surfaces of the three used materials led to crystal precipitation. Salt crystals (e.g. NaCl) have been confirmed through scanning electron microscopy (SEM) and leachate analysis. Both volcanic ash samples as well as the glass beads showed a clear dependency of aggregation efficiency on viscosity of the sprayed HCl solution. Spraying H2SO4 provoked a collapse of the fluidized bed and no aggregation has been observed. This is accounted by the high hygroscopicity of H2SO4. Dissolving CaCl2 (known to be

  13. OncoBinder facilitates interpretation of proteomic interaction data by capturing coactivation pairs in cancer

    PubMed Central

    Zhang, Yao; Wang, Huanbin; Fang, Jing-Yuan; Xu, Jie

    2016-01-01

    High-throughput methods such as co-immunoprecipitationmass spectrometry (coIP-MS) and yeast 2 hybridization (Y2H) have suggested a broad range of unannotated protein-protein interactions (PPIs), and interpretation of these PPIs remains a challenging task. The advancements in cancer genomic researches allow for the inference of “coactivation pairs” in cancer, which may facilitate the identification of PPIs involved in cancer. Here we present OncoBinder as a tool for the assessment of proteomic interaction data based on the functional synergy of oncoproteins in cancer. This decision tree-based method combines gene mutation, copy number and mRNA expression information to infer the functional status of protein-coding genes. We applied OncoBinder to evaluate the potential binders of EGFR and ERK2 proteins based on the gastric cancer dataset of The Cancer Genome Atlas (TCGA). As a result, OncoBinder identified high confidence interactions (annotated by Kyoto Encyclopedia of Genes and Genomes (KEGG) or validated by low-throughput assays) more efficiently than co-expression based method. Taken together, our results suggest that evaluation of gene functional synergy in cancer may facilitate the interpretation of proteomic interaction data. The OncoBinder toolbox for Matlab is freely accessible online. PMID:26872056

  14. Dependence of LiNO3 decomposition on cathode binders in Li-S batteries

    NASA Astrophysics Data System (ADS)

    Godoi, Fernanda Condi de; Wang, Da-Wei; Zeng, Qingcong; Wu, Kuang-Hsu; Gentle, Ian R.

    2015-08-01

    This study brings a new insight into the interfacial compatibility of cathode binders with modified electrolytes in lithium-sulfur batteries. We compared the oxygen-containing binders sodium alginate (NaAlg) and sodium carboxymethyl cellulose (NaCMC) with the conventional oxygen-free polyvinylidene difluoride. The results revealed that the NaAlg and NaCMC binders strongly facilitated the decomposition of the electrolyte additive LiNO3 at potentials lower than 1.8 V. This is primarily attributed to the influence of oxygen-containing functional groups. However, when LiNO3 was absent from the electrolyte, the sulfur cathode with the NaAlg binder showed the most stable performance. To prevent LiNO3 decomposition and acquire stable cycling, the discharge voltage was limited to 1.8 V. At the conclusion of testing (100 cycles, voltage cutoff = 1.8 V), the NaAlg-based cathode maintained 608 mAh g-1 of capacity (52% of the initial capacity). This represented a 35% increase in the specific capacity obtained at the 100th discharge cycle with the cutoff voltage at 1.5 V. Our results suggest a rational choice of the binders used in sulfur composite cathodes.

  15. Affinity Selection of Peptide Binders with Magnetic Beads via Organic Phase Separation (MOPS).

    PubMed

    Murai, Ryuichi; Nogi, Taiki; Tateoka, Komei; Sato, Atsushi

    2015-01-01

    We describe a new method for affinity selection of peptide binders for soluble protein targets using magnetic beads via organic phase separation (MOPS) from a phage display library. As a model target molecule, a mouse monoclonal antibody against human integrin α9β1 (Y9A2) immobilized onto protein G magnetic beads was incubated with a 15-mer or 20-mer random peptide phage-display library. The suspensions containing the phage-magnetic beads conjugates were then transferred onto the organic phase and centrifuged in order to recover the Y9A2 bound phage immobilized on the protein G magnetic beads in the lower organic phase. After three rounds of biopanning, we were able to isolate specific phage clones that could not be obtained by the conventional approach. Furthermore, this new approach was found to be highly effective for isolating phage-binders for Fc-fusion constructs; indeed, enrichment of specific phage-binders was observed after only the first panning cycle. Thus, MOPS can improve the selection of specific phage-binders for soluble protein targets mainly due to the removal of non-specific binders.

  16. Lipid metabolism of commercial layers fed diets containing aflatoxin, fumonisin, and a binder.

    PubMed

    Siloto, E V; Oliveira, E F A; Sartori, J R; Fascina, V B; Martins, B A B; Ledoux, D R; Rottinghaus, G E; Sartori, D R S

    2013-08-01

    Aflatoxins (AF) and fumonisins (FU) are a major problem faced by poultry farmers, leading to huge economic losses. This experiment was conducted to determine the effects of AF (1 mg/kg of feed) and FU (25 mg/kg of feed), singly or in combination, on the lipid metabolism in commercial layers and investigate the efficacy of a commercial binder (2 kg/t of feed) on reducing the toxic effects of these mycotoxins. A total of 168 Hisex Brown layer hens, 37 wk of age, were randomized into a 3 × 2 + 1 factorial arrangement (3 diets with no binder containing AF, FU, and AF+FU; 3 diets with binder containing AF, FU, and AF+FU; and a control diet with no mycotoxins and binders), totaling 7 treatments. The hens contaminated with AF showed the characteristic effects of aflatoxicosis, such as a yellow liver, resulting from the accumulation of liver fat, lower values of plasma very low-density lipoprotein and triglycerides, and higher relative weight of the kidneys and liver. Hepatotoxic and nephrotoxic effects of FU were not observed in this study. On the other hand, the FU caused a reduction in small intestine length and an increase in abdominal fat deposition. The glucan-based binder prevented some of the deleterious effects of these mycotoxins, particularly the effects of AF on hepatic lipid metabolism, kidney relative weight, and FU in the small intestine.

  17. Rheokinetic analysis on the curing process of HTPB-DOA- MDI binder system

    NASA Astrophysics Data System (ADS)

    Chai, T.; Liu, Y. C.; Ma, H.; Yu, Y. W.; Yuan, J. M.; Wang, J. H.; Guo, J. H.

    2016-07-01

    Polymer bonded explosives (PBXs) are a kind of rubbery explosives, in which the explosive components are bound together by a polymeric binder. The hydroxyl terminated polybutadiene (HTPB)-based polyurethane binder systems possess a unique combination of properties, including superior adhesion, excellent mechanical properties and have been widely used in rocket propellants, PBXs and other weapons. The cure reaction between HTPB and diisocyanates in the castable PBXs plays an important role in the adjustment of process parameters as well as properties of explosive formulations. In this paper, viscosity measurements were carried out at different temperatures (15oC, 25oC, 35oC, 45oC, 55oC) to a series of systemic studies on the viscosity build-up and rheological reaction rate constant during the curing process of the of HTPB- dioctyl adipate (DOA)-diphenyl methane diisocyanate (MDI) binder system, discovered and explained the phenomenon that the pot-life of the binder system was prolonged when the curing temperature raised and the curing reaction rate was accelerated. And the rheology kinetic model of the HTPB-DOA-MDI binder system was established.

  18. Properties of Delonix regia seed gum as a novel tablet binder.

    PubMed

    Adetogun, Gbadegesin E; Alebiowu, Gbenga

    2009-01-01

    The mechanical and disintegration properties of paracetamol tablets formulated using Delonix regia seed gum (DRSG) as a binder have been studied in this work. Acacia BP (ACG) and tragacanth BP (TRG) were used as official gum standards. The mechanical properties, i.e. tensile strength (TS) and brittle fracture index (BFI), showed that with an increase in concentration of the gum binder, the tensile strength increased while the BFI was reduced. The crushing strength - friability/disintegration time ratio used to analyze the disintegration properties gave a rank order: tablets containing DRSG > tablets containing ACG > tablets containing TRG at 1%, w/w binder concentration while for higher binder concentrations, the rank order is: tablets containing ACG > tablets containing TRG > tablets containing DRSG. The results suggest that while Delonix regia seed gum may be useful as a binder, its use at a low concentration will improve the balance between the binding and disintegration properties of tablets when a faster disintegration is desired, while its use at a high concentration could serve the desire for a modified or sustained release tablet formulation.

  19. Development of silane-hydrolysate binder for UV-resistant thermal control coatings

    NASA Technical Reports Server (NTRS)

    Patterson, W. J.

    1981-01-01

    Detailed characterizaton and formulation studies were performed on a methyltriakoxysilane hydrolysate as a binder for thermal control coatings. The binder was optimized by varying hydrolysis temperature, time, catalyst type, and water concentration. The candidate coating formulations, based on this binder with TiO2 pigment, were optimized via a detailed series of sprayed test panels that included the parameters of binder/pigment ratio, ethanol content, pigment particle size, coating thickness and cure conditions. A typical optimized coating was prepared by acetic acid catalyzed hydrolysis of methyltriethoxysilane with 3.25 mol-equivalents of water over a 24 hour period at room temperature. The resulting hydrolysate was directly mixed with pre-milled TiO2 (12 grams pigment/26 grams binder) to yield a sprayable consistency. Panels were sprayed to result in a nominal cure coating thickness of 2 mils. Cure was affected by air drying for 24 hr at room temperature plus 72 hr at 150 F. These coatings are typically extremely tough and abrasion-resistant, with an absorptance (alpha) of 0.20 and emittance (e) of 0.89. No significant coating damage was observed in the mandrel bend test, even after exposure to thermal cycling from -160 to 160 F. Vacuum exposure of the coatings for 930 hours at 1 equivalent UV sun resulted in no visible degradation and no significant increase in absorptance.

  20. Strength loss in MA-MOX green pellets from radiation damage to binders

    NASA Astrophysics Data System (ADS)

    Lessing, Paul A.; Cannon, W. Roger; Egeland, Gerald W.; Zuck, Larry D.; Jewell, James K.; Akers, Douglas W.; Groenewold, Gary S.

    2013-06-01

    The fracture strength of green Minor Actinides (MA)-MOX pellets containing 75 wt.% DUO2, 20 wt.% PuO2, 3 wt.% AmO2 and 2 wt.% NpO2 was studied as a function of storage time, after mixing with the binder and before sintering, to test the effect of radiation damage on binders. Fracture strength degraded continuously over the 10 days of the study for all three binders studied: PEG binder (Carbowax 8000), microcrystalline wax (Mobilcer X) and styrene-acrylic copolymer (Duramax B1022) but the fracture strength of Duramax B1022 degraded the least. For instance, for several hours after mixing Carbowax 8000 with MA-MOX, the fracture strength of a pellet was reasonably high and pellets were easily handled without breaking but the pellets were too weak to handle after 10 days. Strength measured using diametral compression test showed that strength degradation was more rapid in pellets containing 1.0 wt.% Carbowax PEG 8000 compared to those containing only 0.2 wt.%, suggesting that irradiation not only left the binder less effective but also reduced the pellet strength. In contrast the strength of pellets containing Duramax B1022 degraded very little over the 10 days period. It was suggested that the styrene portion present in the Duramax B1022 copolymer provided the radiation resistance.