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Sample records for plain concrete pavement

  1. Overlays for plain jointed concrete pavements

    NASA Astrophysics Data System (ADS)

    Gulden, W.; Brown, D.

    1984-09-01

    This report describes the construction and performance of 4 concrete and 16 asphalt overlay test sections after nine years of traffic. The test sections were placed on I-85 which carries a substantial number of heavy trucks to determine what treatments and overlay type and thickness would give acceptable performance. The concrete overlay sections were placed in 1975 and consisted of 3 inch, 4 1/2 inch, and 6 inch CRC and 6 inch jointed PCC with 15 ft. and 30 ft. joint spacing. The asphalt sections were placed in 1976 with the variables being overlay thickness of 2 inches, 4 inches, and 6 inches and the placement of two geotextiles and strips of a waterproofing membrane for each overlay thickness. An Arkansas base test section was also included in the experiment.

  2. Pavement management and rehabilitation of portland cement concrete pavements

    NASA Astrophysics Data System (ADS)

    Zegeer, C. V.; Agent, K. R.; Rizenbergs, R. L.; Curtayne, P. C.; Scullion, T.; Pedigo, R. D.; Hudson, W. R.; Roberts, F. L.; Karan, M. A.; Haas, R.

    Pavement management and rehabilitation projects and techniques are discussed. The following topics are discussed: economic analyses and dynamic programming in resurfacing project selection; implementation of an urban pavement management system; pavement performance modeling for pavement management; illustration of pavement management: from data inventory to priority analysis; rehabilitation of concrete pavements by using portland cement concrete overlays; pavement management study: Illinois tollway pavement overlays; resurfacing of plain jointed-concrete pavements; design procedure for premium composite pavement; model study of anchored pavement; prestressed concrete overlay at O'Hare International Airport: in-service evaluation; and, bonded portland cement concrete resurfacing.

  3. Concrete Block Pavements

    DTIC Science & Technology

    1983-03-01

    Calif. 42 1 •1 90 NEW LEGEND 80 A VIBORG, DENMARK, BLOCKS A VIBORG, DENMARK, ASPHALTIC CONCRETE AFTER 00 MELBOURNE, AUSTRALIA, BLOCKS VIBRATION MEAN ...the load-distributing characteristics of the Mlock pavements. *. 45 -, , - t 171 LEGENDT 0 CONCRETE BASE, MEAN OF 8 TESTS,9 KNAPTON (1978) I RANGE OF...45 to 60 min. 90. Table 11 summarizes the results of these tests. The mean penetration of water through the block pavements with a slope of I per

  4. Precast Concrete Pavements

    DTIC Science & Technology

    1981-11-01

    quirements. The concrete used low-weight sintered shale aggregate and high early-strength portland cement that obtained a 28-day compressive strength of...in- place concrete. Typical reasons suggested for precasting have included aggregate shortage, future pas.oment settlement or heaving, critical speed...pavements. Various devices such as dowel bars, tie bar, keyways, or aggregate interlock from sawn construction joints transfer a portion of the load

  5. The Concrete and Pavement Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The modern world is characterized by the extensive use of concrete and asphalt pavement. Periodically, these materials are replaced and the old materials disposed of. In this challenge, students will be asked to develop ways to reuse the old materials. It is important for students to understand how concrete and asphalt are made and applied, as…

  6. The Concrete and Pavement Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The modern world is characterized by the extensive use of concrete and asphalt pavement. Periodically, these materials are replaced and the old materials disposed of. In this challenge, students will be asked to develop ways to reuse the old materials. It is important for students to understand how concrete and asphalt are made and applied, as…

  7. Maintenance methods for continuously reinforced concrete pavements

    NASA Astrophysics Data System (ADS)

    Yoder, E. J.

    1980-05-01

    Test sections were constructed on a section of 1-65 south of Indianapolis, Indiana to evaluate various maintenance techniques that might be adopted for this type of pavement. The road was stratified into similar sections using deflection, cracking and breakup as selection criteria. Maintenance methods used included concrete shoulders, undersealing, asphalt concrete overlay, subdrains at the pavement edge and various combinations of these methods. In every case the pavement was patched prior to installation of the maintenance.

  8. Importance of dowels in transversal joints in concrete pavements

    NASA Astrophysics Data System (ADS)

    Grosek, Jiri; Chupik, Vladimir; Stryk, Josef; Brezina, Ilja

    2017-09-01

    Concrete pavements are designed for heavy loaded road structures. Their usage brings a number of specific issues. It is necessary to solve them all to ensure that concrete pavements will fulfil their function along the whole design period. One of these issues concerns dowels, which are located in transversal joints. Modelling of load, caused by heavy vehicles, with the use of the finite element method, provides valuable information about the stress condition of concrete pavement. The results of modelling can be verified by measurements or experiments in practice. Dowels and tie bars in jointed unreinforced concrete pavements and the importance of their correct placement, dimensions and material quality on pavement behaviour and lifespan were studied as a part of R&D projects of Technology Agency of the Czech Republic Nos. TA02031195 and TE01020168. The paper presents the experience from the modelling and performed experiments and makes conclusions which are important for the use in practice.

  9. Performance of recycled asphalt concrete airport pavement surfaces

    NASA Astrophysics Data System (ADS)

    Cline, G. D.; Hironaka, M. C.

    1986-10-01

    The objective of this research was to make an assessment of the relative performance of recycled versus new asphalt concrete pavement surfaces constructed for airport facilities. To make this assessment, pavement condition index (PCI) surveys and tests on core samples from the hot-mix recycled pavements located on the airports at Needles, California, and Valley City, North Dakota were conducted. Both pavements have a condition rating of very good. The survey and test data were compared with those for recycled highway and virgin material Navy airfield pavements. The recycle pavement at Needles is performing as good as those Navy pavements constructed with virgin material. The recycled pavement at Valley City has a higher deterioration rate than the Navy pavements but this could be attributed to the harsh climate found in North Dakota. The results of this study show that hot-mix recycling was successful at these airports but additional studies are required to determine the applicability of Asphalt Concrete (AC) recycling for reconstruction at all airports.

  10. The resistance to chloride penetration of concrete containing nano-particles for pavement

    NASA Astrophysics Data System (ADS)

    Zhang, Mao-hua; Li, Hui

    2006-03-01

    The resistance to chloride penetration of concrete containing nano-particles (TiO II and SiO II) for pavement is experimentally investigated and compared with that of plain concrete, the concrete containing polypropylene (PP) fibers and the concrete containing both nano-particles and PP fibers. The test results indicate that the addition of nano-particles (TiO II and SiO II) improves the resistance to chloride penetration of concrete. The effectiveness of nano-TiO II in improving the resistance to chloride penetration reduces with increasing content of nano-TiO II, and the similar results can be found for the concrete containing nano-SiO II. The resistance to chloride penetration of concrete containing nano-TiO II is better than that containing the same amount of nano-SiO II. However, the resistance to chloride penetration of concrete containing PP fibers is decreased. The larger the content of PP fibers is, the lower the resistance to chloride penetration of concrete is. For the concrete containing both nano-particles and PP fibers, the resistance to chloride penetration is also reduced and even lower than the concrete only containing the same amount of PP fibers. The relationship between the chloride diffusion coefficient and compressive strength of concrete approaches hyperbola basically, which shows that the resistance to chloride penetration of concrete enhances with increasing compressive strength and proves that compressive strength is an important factor influencing the resistance to chloride penetration of concrete.

  11. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

    PubMed Central

    Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

    2015-01-01

    Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability. PMID:28793518

  12. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash.

    PubMed

    Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

    2015-08-21

    Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability.

  13. Thin, applied surfacing for improving skid resistance of concrete pavements

    NASA Astrophysics Data System (ADS)

    Scholer, C. F.

    1980-12-01

    The use of select aggregate in a thin wearing surface of portland cement mortar to prolone or restore a concrete pavement's ability to develop high friction was accomplished. Two fine aggregates, blast furnace slag and lightweight expanded shale were found to exhibit skid resistance greater than the other aggregates evaluated. The British polishing wheel was used in the laboratory evaluation of aggregate to simulate wear. The need for a method of restoring friction to a worn, but otherwise sound concrete pavement led to a field evaluation of several different techniques for placing a very thin overlay. The successful method was a broomed, very thin layer of mortar, 3 mm thick.

  14. Criteria for Polymer Concrete on Airport Pavements

    DTIC Science & Technology

    1989-07-27

    basins against corrosion and erosion due to sand and other abrasive materials carried by the flowing waters. Other examples of the Corps of Engineers...airport pavement involves the following 6 design parameters; 1. load specifications (magnitude, geometry , frequency etc.), 2. pavement and subgrade...specifications ( geometry , material properties) and 3. allowable stresses and deflections in the system. It is assumed that all the above parameters except

  15. Precast concrete pavement – systems and performance review

    NASA Astrophysics Data System (ADS)

    Novak, Josef; Kohoutková, Alena; Křístek, Vladimír; Vodička, Jan

    2017-09-01

    Long-term traffic restrictions belong to the key disadvantages of conventional cast-in-plane concrete pavements which have been used for technical structures such as roads, parking place and airfield pavements. As a consequence, the pressure is put on the development of such systems which have short construction time, low production costs, long-term durability, low maintenance requirements etc.. The paper presents the first step in the development of an entirely new precast concrete pavement (PCP) system applicable to airfield and highway pavements. The main objective of the review of PCP systems is to acquire a better understanding of the current systems and design methods used for transport infrastructure. There is lack of information on using PCP systems for the construction of entirely new pavements. To most extensive experience is dated back to the 20th century when hexagonal slab panels and system PAG were used in the Soviet Union for the military airfields. Since cast-in-situ pavements became more common, the systems based on precast concrete panels have been mainly utilized for the removal of damaged sections of existing structures including roads, highways etc.. Namely, it concerns Fort Miller Super Slab system, Michigan system, Uretek Stitch system and Kwik system. The presented review indicates several issues associated with the listed PCP systems and their applications to the repair and rehabilitation of existing structures. Among others, the type of manufacturing technology, particularly the position of slots for dowel bars, affects the durability and performance of the systems. Gathered information serve for the development of a new system for airfield and highway pavement construction.

  16. Grout Impregnation of Pre-Placed Recycled Concrete Pavement (RCP) for Rapid Repair of Deteriorated Portland Cement Concrete Airfield Pavement

    DTIC Science & Technology

    2007-04-01

    aggregates in the repair hole, and the voids are filled with a rapid-setting, flowable grout. The results of this study will be used to provide...the repair of spalls involve filling the damaged area with some type of flowable substance which hardens to provide a material that has comparable... filled with Recycled Concrete Pavement (RCP)........................................................................ 53 7 Mixing Pavemend™ material

  17. Analytical Study of Concrete Pavement Behavior

    DTIC Science & Technology

    1989-12-17

    are quoted in the literature as "questionable". 2.b.6 Other Finite Element Methodologies Larralde and Chen [15] conducted a research study at Purdue...Applied Mechanics, Transactions, ASME, Vol. 31, No. 3, 1964. 15. Larralde , J. and Chen, W. F., "Computer Model for Analysis of Rigid Pavements with

  18. AN OPTIMAL MAINTENANCE MANAGEMENT MODEL FOR AIRPORT CONCRETE PAVEMENT

    NASA Astrophysics Data System (ADS)

    Shimomura, Taizo; Fujimori, Yuji; Kaito, Kiyoyuki; Obama, Kengo; Kobayashi, Kiyoshi

    In this paper, an optimal management model is formulated for the performance-based rehabilitation/maintenance contract for airport concrete pavement, whereby two types of life cycle cost risks, i.e., ground consolidation risk and concrete depreciation risk, are explicitly considered. The non-homogenous Markov chain model is formulated to represent the deterioration processes of concrete pavement which are conditional upon the ground consolidation processes. The optimal non-homogenous Markov decision model with multiple types of risk is presented to design the optimal rehabilitation/maintenance plans. And the methodology to revise the optimal rehabilitation/maintenance plans based upon the monitoring data by the Bayesian up-to-dating rules. The validity of the methodology presented in this paper is examined based upon the case studies carried out for the H airport.

  19. Polypropylene Fibers in Portland Cement Concrete Pavements.

    DTIC Science & Technology

    1992-08-01

    Bibliography on Fiber- Reinforced Cement and Concrete," Miscellaneous Paper C-76-6, with supplements 1, 2, 3, and 4 ( 1977 , 1979, 1980, and 1982), US Army... Mindess , S., Bentur, A., Yan, C., and Vondran, G., "Impact Resistance of Concrete Containing Both Conventional Steel Reinforcement and Fibrillated...Roads, Streets, Walks, and Open Storage Areas," TM 5-822-6/AFM 88-7, Chap. 7, Washington, DC, 1977 . 18. __ , "Concrete Floor Slabs on Grade Subjected

  20. Performance of concrete pavements containing recycled concrete aggregate. Interim report, October 1993-October 1996

    SciTech Connect

    Wade, M.J.; Cuttell, G.D.; Vandenbossche, J.M.; Yu, H.T.; Smith, K.D.

    1997-03-01

    This interim report documents the field performance of nine concrete pavement projects that incorporate recycled concrete aggregate (RCA) in the construction of the pavement. Multiple sections were evaluated on many of the nine projects, due to perceived differences in performance levels or variations in pavement design (such as the use of virgin aggregate or the inclusion of dowel bars). All told, a total of 17 sections (of which 12 contain RCA) were subjected to an extensive field testing program, consisting of pavement condition surveys, drainage surveys, falling weight deflectometer (FWD) testing, coring, and serviceability assessments. A minimum of eight cores were retrieved from each section for laboratory evaluation of compressive strength, split tensile strength, dynamic elastic modulus, static elastic modulus, and thermal coefficient of expansion, as well as for volumetric surface testing and petrographic analyses.

  1. Friction evaluation of concrete paver blocks for airport pavement applications

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.

    1992-01-01

    The development and use of concrete paver blocks is reviewed and some general specifications for application of this type of pavement surface at airport facilities are given. Two different shapes of interlocking concrete paver blocks installed in the track surface at NASA Langley's Aircraft Landing Dynamics Facility (ALDF) are described. Preliminary cornering performance results from testing of 40 x 14 radial-belted and bias-ply aircraft tires are reviewed. These tire tests are part of a larger, ongoing joint NASA/FAA/Industry Surface Traction and Radial Tire (START) Program involving several different tire sizes. Both dry and wet surface conditions were evaluated on the two concrete paver block test surfaces and a conventional, nongrooved Portland cement concrete surface. Future test plans involving evaluation of other concrete paver block designs at the ALDF are indicated.

  2. Friction evaluation of concrete paver blocks for airport pavement applications

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.

    1992-01-01

    The development and use of concrete paver blocks is reviewed and some general specifications for application of this type of pavement surface at airport facilities are given. Two different shapes of interlocking concrete paver blocks installed in the track surface at NASA Langley's Aircraft Landing Dynamics Facility (ALDF) are described. Preliminary cornering performance results from testing of 40 x 14 radial-belted and bias-ply aircraft tires are reviewed. These tire tests are part of a larger, ongoing joint NASA/FAA/Industry Surface Traction and Radial Tire (START) Program involving several different tire sizes. Both dry and wet surface conditions were evaluated on the two concrete paver block test surfaces and a conventional, nongrooved Portland cement concrete surface. Future test plans involving evaluation of other concrete paver block designs at the ALDF are indicated.

  3. User's guide: Hot-mix recycling of asphalt concrete pavements

    NASA Astrophysics Data System (ADS)

    Shoenberger, James E.

    1993-05-01

    This guide provides the technical information required to implement the application of hot-mix recycling of asphalt concrete pavements. Included are details on application, benefits/advantages, limitations/disadvantages, and costs associated with this technology. Information is provided on three demonstration sites at Fort Gillem, Georgia; Fort Leavenworth, Kansas; and Fort Benjamin Harrison, Indiana. 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 appendices.

  4. 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.

  5. Prestressed Concrete Pavements. Volume II. Design and Construction Procedures for Civil Airports.

    DTIC Science & Technology

    PAVEMENTS, *CONSTRUCTION, *AIRPORTS, STRESSES, THICKNESS, LOADS(FORCES), STATIC LOADS, MODEL TESTS, FLEXURAL STRENGTH, CREEP, STANDARDS, FRICTION, SHRINKAGE, TENDONS , PRESTRESSED CONCRETE, EXPANSION JOINTS.

  6. Graded Viscoelastic Approach for Modeling Asphalt Concrete Pavements

    NASA Astrophysics Data System (ADS)

    Dave, Eshan V.; Buttlar, William G.; Paulino, Glaucio H.; Hilton, Harry H.

    2008-02-01

    Asphalt concrete pavements exhibit severely graded properties through their thickness due to oxidative aging effects, which are most pronounced at the surface of the pavement and decrease rapidly with depth from the surface. Most of the literature to date has focused on use of layered-elastic models for the consideration of age stiffening. In the current work, a graded viscoelastic model has been implemented within a numerical framework for the simulation of asphalt pavement responses under thermal and mechanical loading. The graded viscoelastic work is extension of the previous work by Paulino and Jin [1], Mukherjee and Paulino [2], and Buttlar et al. [3]. A functionally graded generalized Maxwell model has been used in the development of a constitutive model for asphalt concrete considering aging and temperature gradients. The aging gradient data from laboratory test results reported by Apeagyei [4] is used for obtaining material properties for the graded viscoelastic model. Finite element implementation of the constitutive model incorporates the generalized iso-parametric formulation (GIF) proposed by Kim and Paulino [5], which leads to the graded viscoelastic elements used in this work.

  7. User’s Guide: Cracking and Seating of Portland Cement Concrete Pavements

    DTIC Science & Technology

    1992-08-01

    Concrete Pavements 6. AUTHOR(S) Randy C. Ahlrich 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER USAE...OF PAGES Asphalt concrete Maintenance 29 Concrete Repair 16. PRICE CODE Cracking Seating OF REPORT OF THIS PAGE d OF ABSTRACT Unclassified Unclassified...Seated Concrete ," Transportation Research Record 1215, Washington, DC. Ahlrich, R. C. and Godwin, L. N. 1991. "Cracking and Seating of PCC Pavements

  8. Polymer concrete for precast repair of continuously reinforced concrete pavement on IH 30, near Mt. Pleasant

    NASA Astrophysics Data System (ADS)

    Meyer, A. M.; McCullough, B. F.; Fowler, D. W.

    1981-08-01

    Two punchout repairs made in a continuously reinforced concrete pavement (CRCP) using precast portland cement panels are described. The two repairs, one 1.44 sq. ft., the other 36 sq. ft., were completed and opened to traffic in one afternoon. This technique provides a rapid method of repair that produces a repair that is structurally as good or better than the surrounding pavement. With a trained crew, the repair time can be reduced and thus reducing lane closure time. Since lane closure time is a critical consideration in high volume highways, this method is cost effective in those areas.

  9. Pre-Cast Concrete Panels for Contingency Rigid Airfield Pavement Damage Repairs

    DTIC Science & Technology

    2010-06-01

    Figure 16. Swift-Lift Installation into Precast Concrete Panel ..................................................... 14 Figure 17. Wall -Saw Cutting... Wall -saw and walk-behind concrete saw). Table 6 is a precast concrete panel fabrication timeline and Table 7 is precast panel placement timeline...AFRL-RX-TY-TR-2010-0095 PRECAST CONCRETE PANELS FOR CONTINGENCY RIGID AIRFIELD PAVEMENT DAMAGE REPAIRS Reza S. Ashtiani, Christopher J

  10. Analysis of Load Stress for Asphalt Pavement of Lean Concrete Base

    NASA Astrophysics Data System (ADS)

    Lijun, Suo; Xinwu, Wang

    The study revealed that whether it is early distresses in asphalt pavement or not depends largely on working performance of base. In the field of asphalt pavement, it is widely accepted that lean concrete base, compared with the general semi-rigid base, has better working performance, such as high strength and good eroding resistance. Problem of early distresses in asphalt pavement, which caused by more traffic loadings, can be settled effectively when lean concrete is used in asphalt pavement. Traffic loading is important parameter used in the analysis of the new pavement design. However, few studies have done extensive and intensive research on the load stress for asphalt pavement of lean concrete base. Because of that, it is necessary to study the load stress for the asphalt pavement. In the paper, first of all, three-dimension finite element model of the asphalt pavement is created for the aim of doing mechanical analysis for the asphalt pavement. And then, the two main objectives of this study are investigated. One is analysis for load stress of lean concrete base, and the other is analysis for load stress of asphalt surface. The results show that load stress of lean concrete base decreases, decrease and increase with increase of base's thickness, surface's thickness and ratio of base's modulus to foundation's modulus respectively. So far as the asphalt surface is concerned, maximum shearing stress, which is caused by load, is evident in asphalt surface which is located in transverse contraction joint of lean concrete base of asphalt pavement. Maximum shearing stress decrease, decrease, decrease and increase respectively with increase of the surface's modulus, the surface's thickness, base's thickness and ratio of base's modulus to foundation's modulus.

  11. The pollination biology of a pavement plain: pollinator visitation patterns.

    PubMed

    O'Brien, Mary H

    1980-01-01

    The pollination biology of the 20 plant species of a treeless, pavement plain in the San Bernardino Mountains of southern California was studied throughout one flowering season.Several patterns of pollinator activity recorded during the season underline the necessity for noting the activity of all insect pollinators whether specialized, non-specialized, regular, or occasional: 1) Occasional insect visitors were a feature of the visitation to nine of the twelve entomophilous plant species and were the sole pollinators for three of these twelve species. 2) The eight entomophilous plant species which had open, generalized flower morphologies received the heaviest pollinator visitation, while three of the four entomophilous species with specialized flower morphologies received little visitation. 3) Most regular flower visitors, whether bees, flies, or wasps, appeared to be similar with respect to number of plant species visited regularly, purity of pollen load, length of residence and localization of activity on the site. The question is raised as to whether such similarity of behavior as pollen vectors is a function of the low plant diversity or a feature commonly found when the pollen loads and behavior of different pollinator types are actually monitored.

  12. Study of Asphaltic Concrete Produced in Dryer Drum Mixers for Airport Pavements.

    DTIC Science & Technology

    1976-10-01

    STWDARDS-163- w S 4 -- , ,a, i I Report No-c FAA-RD-76-165 STUDY OF ASPHALTIC CONCRETE PRODUCED IN DRYER DRUM MIXERS FOR AIRPORT PAVEMENTS 0 E. T...PREFACE This study was supported by the Systems Research and Development Service of the Federal Aviation Administration. This is a final report presenting...the asphaltic concrete . In September, 1976 the Alaskan Region of FAA reported that the runway pavement had transverse thermal cracks approximately 200

  13. Engineering and Design: Design and Construction Management Practices for Concrete Pavements

    DTIC Science & Technology

    1998-03-01

    Construction Division ETL 1110-3-488 1 Mar 98 APPENDIX A: REFERENCES 1. TM 5-822-5 ( AFM 88-7, Chap. 1), "Pavement Design for Roads, Streets, Walks, and Open...Storage Areas." 2. TM 5-822-7 ( AFM 88-6, Chap. 8), "Standard Practice for Concrete Pavements." 3. TM 5-825-1 (AFJMAN 32-8008, Vol. 1), "General...Provisions for Airfield/Heliport Pavement Design." 4. TM 5-825-3 ( AFM 88-6, Chap. 3), "Rigid Pavements for Airfields." 5. EM 1110-2-2000, “Standard

  14. Early-life study of the FA409 full-depth asphalt-concrete pavement sections

    SciTech Connect

    Hill, H.J.

    1988-01-01

    The Illinois Department of Transportation (IDOT) is currently implementing a mechanistic thickness-design procedure for full-depth asphalt-concrete pavements. This thesis is an early design-life investigation of full-depth asphalt-concrete pavements, constructed on FA409 near Carlyle, Illinois in 1986. Included in the study are: sampling and testing of paving and subgrade materials; extensive non-destructive testing (NDT) using the Falling Weight Deflectometer (FWD); development of techniques for interpreting NDT data; determination of as-built structural characteristics of the various pavement sections; evaluation of subsurface drainage and lime-treated soil behavior; and examination of the validity of the ILLI-PAVE computer model. The simplicity of a full-depth asphalt-concrete pavement allows useful information regarding pavement structure to be determined from FWD surface-deflection data. The ILLI-PAVE model was used in conjunction with statistical methods to quantify, in the form of regression equations or algorithms, the relationship between pavement structure (Tac, Eac, and Eri) and pavement response to FWD loading. Testing of pavement and subgrade material samples as used to validate these algorithms.

  15. Recycling of portland cement concrete pavement, Johnson County. Final report, 1986-1995

    SciTech Connect

    Wojakowski, J.B.; Fager, G.A.; Catron, M.A.

    1995-08-01

    In recent years there has been increasing interest in recycling construction materials. Surface courses of bituminous pavements are currently being actively recycled all over Kansas. The recycling of portland cement concrete pavements (PCCP) can help alleviate any material disposal problems during construction, especially in urban areas and reduce the consumption or importation of virgin aggregate into aggregate poor areas. Two test sections using the coarser fraction from the original crushed portland cement concrete pavement were placed on K-7 in 1985. One section incorporated a recycled base and standard PCCP construction, another section was designed as a recycled base and recycled PCCP. Two other sections were control sections constructed with regular aggregate.

  16. 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.

  17. The Greenhouse Gas Emission from Portland Cement Concrete Pavement Construction in China.

    PubMed

    Ma, Feng; Sha, Aimin; Yang, Panpan; Huang, Yue

    2016-06-24

    This study proposes an inventory analysis method to evaluate the greenhouse gas (GHG) emissions from Portland cement concrete pavement construction, based on a case project in the west of China. The concrete pavement construction process was divided into three phases, namely raw material production, concrete manufacture and pavement onsite construction. The GHG emissions of the three phases are analyzed by a life cycle inventory method. The CO₂e is used to indicate the GHG emissions. The results show that for 1 km Portland cement concrete pavement construction, the total CO₂e is 8215.31 tons. Based on the evaluation results, the CO₂e of the raw material production phase is 7617.27 tons, accounting for 92.7% of the total GHG emissions; the CO₂e of the concrete manufacture phase is 598,033.10 kg, accounting for 7.2% of the total GHG emissions. Lastly, the CO₂e of the pavement onsite construction phase is 8396.59 kg, accounting for only 0.1% of the total GHG emissions. The main greenhouse gas is CO₂ in each phase, which accounts for more than 98% of total emissions. N₂O and CH₄ emissions are relatively insignificant.

  18. The Greenhouse Gas Emission from Portland Cement Concrete Pavement Construction in China

    PubMed Central

    Ma, Feng; Sha, Aimin; Yang, Panpan; Huang, Yue

    2016-01-01

    This study proposes an inventory analysis method to evaluate the greenhouse gas (GHG) emissions from Portland cement concrete pavement construction, based on a case project in the west of China. The concrete pavement construction process was divided into three phases, namely raw material production, concrete manufacture and pavement onsite construction. The GHG emissions of the three phases are analyzed by a life cycle inventory method. The CO2e is used to indicate the GHG emissions. The results show that for 1 km Portland cement concrete pavement construction, the total CO2e is 8215.31 tons. Based on the evaluation results, the CO2e of the raw material production phase is 7617.27 tons, accounting for 92.7% of the total GHG emissions; the CO2e of the concrete manufacture phase is 598,033.10 kg, accounting for 7.2% of the total GHG emissions. Lastly, the CO2e of the pavement onsite construction phase is 8396.59 kg, accounting for only 0.1% of the total GHG emissions. The main greenhouse gas is CO2 in each phase, which accounts for more than 98% of total emissions. N2O and CH4 emissions are relatively insignificant. PMID:27347987

  19. Pavement-management system for concrete roadways in Virginia. Phase 1. Condition ratings. Final report

    SciTech Connect

    Long, R.R.

    1988-04-01

    The report traces the development of a rating system for evaluating the service condition of Virginia's portland-cement concrete pavements. The service condition is assessed in terms of distress roughness, i.e., that portion of a pavement's poor-ride characteristics directly attributable to the occurrence of certain key distress types. Field surveys of the occurrence of these distresses provide the necessary data for estimating distress roughness through the use of prediction equations that have been established from the standard statistical analysis of pavement-section distress data and roughness measurements. Distress measurements and their corresponding ratings and a condition survey rating procedure are appended.

  20. Effects of street tree shade on asphalt concrete pavement performance

    Treesearch

    E.G. McPherson; J. Muchnick

    2005-01-01

    Forty-eight street segments were paired into 24 high-and low-shade pairs in Modesto, California, U.S. Field data were collected to calculate a Pavement Condition Index (PCI) and Tree Shade Index (TSI) for each segment. Statistical analyses found that greater PCI was associated with greater TSI, indicating that tree shade was partially responsible for reduced pavement...

  1. Evaluation of non-metallic fiber reinforced concrete in new full depth pcc pavements. Final report

    SciTech Connect

    Ramakrishnan, V.; Tolmare, N.S.

    1998-12-30

    This final report presents the construction and performance evaluation of a new full depth pavement, constructed with a new type non-metallic fiber reinforced concrete (NMFRC). The mixture proportions used, the quality control tests conducted for the evaluation of the fresh and hardened concrete properties, the procedure used for mixing, transporting, placing, consolidating, finishing, and curing of the concrete are described. Periodic inspection of the full depth pavement was done and this report includes the results of these inspections. The feasibility of using this NMFRC in the construction of highway structures has been discussed. The new NMFRC with enhanced fatigue, impact resistance, modulus of rupture, ductility and toughness properties is suitable for the construction of full depth pavements. However, a life-cycle cost analysis shows that NMFRC is not a favorable choice, because of it`s high initial cost.

  2. Flying blind: designing and maintaining jointed concrete pavement without monitoring pavement pressure generation

    NASA Astrophysics Data System (ADS)

    Burke, Martin P., Jr.

    2001-08-01

    The generation of longitudinal pavement pressures or growth of jointed-rigid pavement have been recognized by many engineers for at least a century. The manifestations of this pressure/growth phenomenon, in the form of progressive pavement and bridge damage, are vivid examples of its destructive potential. Yet, only a few researchers have attempted to measure the pressures generated by this phenomenon. None, to the author's knowledge, have attempted to periodically monitor pressure generation for the purpose of either determining and describing pressure generation characteristics or predicting the probability of its abrupt final and destructive manifestations. Because the pavement/growth phenomenon occurs over such a long period of time (a decade or more), it is generally unrecognized, or if recognized, it is poorly understood. Consequently, design and maintenance of jointed rigid pavement continues to be guided more by intuition and personal judgement rather than be replicated research and professional consensus. This paper provides a speculative description of the pavement pressure/growth phenomenon. It also contains an appeal to research professionals to develop instrumentation suitable to monitor generating pavement pressures. The results of such research should finally enable the transportation profession to establish suitable background so that future pavement design and maintenance will be guided so that pressure generation will be minimized and pavement and bridge function and durability will be improved. Otherwise, transportation systems will continue to experience progressive and substantial pavement and bridge damage, commensurate repair costs, and the traveling public will continue to be exposed to occasional but abrupt manifestations of its destructive potential.

  3. Criteria for Asphalt-Rubber Concrete in Civil Airport Pavements. Volume 2. Evaluation of Asphalt-Rubber Concrete.

    DTIC Science & Technology

    1987-03-01

    194 ix LIST OF TABLES Table Page 1 1977 FAA Aggregate Grading Band for Bituminous Surface Course with 1/2" (12.5m) Maximum Particle Size* ...... 6 2...Asphalt Concrete and Asphalt-Rubber Concrete. . . . . . . . . . . . . . . . . . . . . . . . . 106 xi LIST OF FthJiJRf1 Figure Page 1 1977 FAA...were blended to meet the 1977 FAA aggregate grading specification for pavements with a bituminous surface course and designed to accommodate aircraft

  4. United States Air Force Research on Airfield Pavement Repairs Using Precast Portland Cement Concrete (PCC) Slabs (BRIEFING SLIDES)

    DTIC Science & Technology

    2008-08-28

    AFRL-RX-TY-TP-2008-4582 POSTPRINT UNITED STATES AIR FORCE RESEARCH ON AIRFIELD PAVEMENT REPAIRS USING PRECAST PORTLAND CEMENT CONCRETE ...pavement Portland cement concrete (PCC) slab repairs using precast PCC slab panels. AFRL is leading the technology development by critically reviewing the...technology transfer activities including, but not limited to, training, reports and preparation of ETLs. 2 The use of precast concrete slabs for repair of

  5. Condition assessment of concrete pavements using both ground penetrating radar and stress-wave based techniques

    NASA Astrophysics Data System (ADS)

    Li, Mengxing; Anderson, Neil; Sneed, Lesley; Torgashov, Evgeniy

    2016-12-01

    Two stress-wave based techniques, ultrasonic surface wave (USW) and impact echo (IE), as well as ground penetrating radar (GPR) were used to assess the condition of a segment of concrete pavement that includes a layer of concrete, a granular base and their interface. Core specimens retrieved at multiple locations were used to confirm the accuracy and reliability of each non-destructive testing (NDT) result. Results from this study demonstrate that the GPR method is accurate for estimating the pavement thickness and locating separations (air voids) between the concrete and granular base layers. The USW method is a rapid way to estimate the in-situ elastic modulus (dynamic elastic modulus) of the concrete, however, the existence of air voids at the interface could potentially affect the accuracy and reliability of the USW test results. The estimation of the dynamic modulus and the P-wave velocity of concrete was improved when a shorter wavelength range (3 in. to 8.5 in.) corresponding to the concrete layer thickness was applied instead of the full wavelength rage (3 in. to 11 in.) based on the standard spacing of the receiver transducers. The IE method is proved to be fairly accurate in estimating the thickness of concrete pavements. However, the flexural mode vibration could affect the accuracy and reliability of the test results. Furthermore, the existence of air voids between the concrete and granular base layers could affect the estimation of the compression wave velocity of concrete when the full wavelength range was applied (3 in. to 11 in.). Future work is needed in order to improve the accuracy and reliability of both USW and IE test results.

  6. Effect of Nano Silica on the Physical Property of Porous Concrete Pavement

    NASA Astrophysics Data System (ADS)

    Yusak, Mohd Ibrahim Mohd; Ezree Abdullah, Mohd; Putra Jaya, Ramadhansyah; Rosli Hainin, Mohd; Ibrahim, Mohd Haziman Wan

    2017-08-01

    Rice husk can be categorized as an organic waste material from paddy industries. Silica is a major inorganic element of the rice husk. The aim of present study is to evaluate the effect of Nano silica on the physical properties of porous concrete pavement. Rice husk has been burned in the furnace (650°C for 6 hours) and ground for four different grinding times (33, 48, 63 and 81 hours). Five types of mixes were prepared to evaluate the different Nano silica grinding time. A Nano silica dosage of 10% by weight of binder was used throughout the experiments. The physical properties were examined through compressive strength, transmission electron microscopy and x-ray fluorescence. The experimental results indicate that the different Nano size gives a different effect to porous concrete strength. Based on the results obtained, Nano silica ground for 63 hours (65.84nm) gives the best result and performance to porous concrete pavement specimens.

  7. 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.

  8. Application of infrared camera to bituminous concrete pavements: measuring vehicle

    NASA Astrophysics Data System (ADS)

    Janků, Michal; Stryk, Josef

    2017-09-01

    Infrared thermography (IR) has been used for decades in certain fields. However, the technological level of advancement of measuring devices has not been sufficient for some applications. Over the recent years, good quality thermal cameras with high resolution and very high thermal sensitivity have started to appear on the market. The development in the field of measuring technologies allowed the use of infrared thermography in new fields and for larger number of users. This article describes the research in progress in Transport Research Centre with a focus on the use of infrared thermography for diagnostics of bituminous road pavements. A measuring vehicle, equipped with a thermal camera, digital camera and GPS sensor, was designed for the diagnostics of pavements. New, highly sensitive, thermal cameras allow to measure very small temperature differences from the moving vehicle. This study shows the potential of a high-speed inspection without lane closures while using IR thermography.

  9. Assessment of Asphalt Concrete Reinforcement Grid in Flexible Pavements

    DTIC Science & Technology

    2016-05-01

    Flexible Pavements Lynette A. Barna, Charles E. Smith Jr., and Andrew Bernier U.S. Army Engineer Research and Development Center (ERDC) Cold Regions...Development Center (ERDC) Cold Regions Re- search and Engineering Laboratory (CRREL), and Aaron Smart and Ann Scholz, NHDOT Bureau of Materials and...Association of State Highway and Transportation Officials CBR California Bearing Ratio CRREL Cold Regions Research and Engineering Laboratory CRADA

  10. Testing of plain and fibrous concrete single cavity prestressed concrete reactor vessel models

    SciTech Connect

    Oland, C.B.

    1985-01-01

    Two single-cavity prestressed concrete reactor vessel (PCRV) models were fabricated and tested to failure to demonstrate the structural response and ultimate pressure capacity of models cast from high-strength concretes. Concretes with design compressive strengths in excess of 70 MPa (10,000 psi) were developed for this investigation. One model was cast from plain concrete and failed in shear at the head region. The second model was cast from fiber reinforced concrete and failed by rupturing the circumferential prestressing at the sidewall of the structure. The tests also demonstrated the capabilities of the liner system to maintain a leak-tight pressure boundary. 3 refs., 4 figs.

  11. Construction Productivity Advancement Research (CPAR) Program: Improved Materials and Processes for Sealing and Resealing Joints in Portland Cement Concrete Pavements - Field Evaluation

    DTIC Science & Technology

    1993-10-01

    compositions of material- are currently used for scaling portland cement concrete (PCC) joints . These materials vary widely in chemi- cal complexity...PRODUCTIVITY ADVANCEMENT RESEARCH (CPAR) PROGRAM Improved Materials and Processes for Sealing and Resealing Joints in Portland Cement Concrete Pavements...Processes for Sealing and Resealing Joints in Portland Cement Concrete Pavements-Field Evaluation by Larry N. Lynch, Dewey W. White Accesion

  12. An assessment of SBS modified asphalt concrete pavements performance features performing numerical analysis

    NASA Astrophysics Data System (ADS)

    Karakas, Ahmet Sertac; Bozkurt, Tarik Serhat; Sayin, Baris; Ortes, Faruk

    2017-07-01

    In passenger and freight traffic on the roads, which has the largest share of the hot mix asphalt (HMA) prepared asphalt concrete pavement is one of the most preferred type of flexible superstructure. During the service life of the road, they must provide the performance which is expected to show. HMA must be high performance mix design, comfortable, safe and resistance to degradation. In addition, it becomes a critical need to use various additives materials for roads to be able to serve long-term against environmental conditions such as traffic and climate due to the fact that the way of raw materials is limited. Styrene Butadiene Styrene (SBS) polymers are widely used among additives. In this study, the numerical analysis of SBS modified HMA designed asphalt concrete coatings prepared with different thicknesses with SBS modified HMA is performed. After that, stress and deformation values of the three pavement models are compared and evaluated.

  13. Producing Durable Continuously Reinforced Concrete Pavement using Glass-ceramic Coated Reinforcing Steel

    DTIC Science & Technology

    2010-02-01

    BUILDING STRONG® Producing Durable Continuously Reinforced Concrete Pavement using Glass- ceramic Coated Reinforcing Steel Principal Investigator... ceramic Coated Reinforcing Steel 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER...Vitreous- Ceramic Coating  Ease of Application to Reinforcement Steel  Bond Strength and Corrosion-Resistance  Field Demonstration Program  Testing in

  14. Predicting the behavior of asphalt concrete pavements in seasonal frost areas using nondestructive techniques

    NASA Astrophysics Data System (ADS)

    Janoo, Vincent C.; Berg, Richard L.

    1990-11-01

    Four different pavement test sections were subjected to freeze-thaw cycling in the Frost Effects Research Facility (FERF). The test sections, each 610 cm in length, consisted of 15.2 cm of asphalt concrete pavement over a clay subgrade; 15.2 cm of asphalt concrete over 10.2 cm of crushed gravel over a clay subgrade; 5.1 cm of asphalt over 17.8 cm of crushed gravel over 20.3 cm of clean sand over a clay subgrade; and 5.1 cm of asphalt concrete over 25.4 cm of crushed gravel over 12.7 cm of clean sand over clay subgrade. Thermocouples were imbedded throughout the pavement structure and subgrade. During the thawing periods, deflection measurements were made at four locations in each test section using a Dynatest Falling Weight Deflectometer (FWD). The results of the deflection measurement are presented here. An analysis was done to qualify the subgrade strength based solely on FDW measurements. It was also shown that a relationship existed between thaw depth and FWD measurement in the subgrade.

  15. Use of crushed concrete products in Minnesota pavement foundations. Final report, 1987-1994

    SciTech Connect

    Synder, M.B.

    1995-03-01

    The report reviews eleven field and laboratory studies that have been performed to address concerns about the use of recycled concrete aggregate in pavement foundations. Performance concerns have centered on the possible impairment of drainage systems by deposits of calcium carbonate precipitate and other fines derived from the recycled concrete base materials. Environmental concerns have focused on the relatively high pH of the effluent produced by drainage systems that remove water from ungreated recycled concrete aggregate foundation layers. The studies considered in the report demonstrate that all recycled concrete aggregates are capable of producing various amounts of precipitate, with the precipitate potential being directly related to the amount of freshly exposed cement mortar surface. It appears that selective grading and blending with virgin aggregates are techniques that should significantly reduce precipitate potential. One study suggests that washing recycled concrete products will reduce accumulations of crusher dust and other fines in and around the pavement drains. Others indicate that the use of filter fabrics with sufficiently high initial permittivity will allow the accumulation of precipitate and other fines without significant impairing drainage function. The report discusses study results related to environmental concerns and provides recommendations for revisions to current specifications.

  16. Current Practices on Nighttime Pavement Construction Asphaltic Concrete.

    DTIC Science & Technology

    1982-07-01

    foot width. This production amounted to approximately 1520 tons per night. 9. Equipment: a. Asphalt Spreader. The Contractor utilized one Blaw Knox ...Diego, CA. to monitor the testing of the Port Authority requirements. 11. Grade Control Requirements. a. Ski. The Blaw Knox paving machine was specified...q 16. Crack Reflection Membrane: None. 17. Hot Mix Asphaltic Concrete Overlay Placing: a. Asphalt Spreaders Operating in Echelon. Only one Blaw - Knox

  17. BEHAVIOR OF INSTRUMENTED PRESTRESSED CONCRETE PAVEMENT AT NAS LEMOORE, CALIFORNIA

    DTIC Science & Technology

    Longitudinal and transverse post-tensioning loads and the distribution of these forces along the lengths of tendons were defined by calibrated links...or couplers installed in the tendons . Strains induced in the concrete by stressing and existing for several months after stressing were measured by...the measurement of pressures under the load. There was apparently a substantial amount of friction between longitudinal tendons and their ducts as

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

    NASA Astrophysics Data System (ADS)

    Park, Hong Joon

    This dissertation presents causes of cracking in asphalt concrete pavement in North Carolina through field investigation and laboratory experiments with field extracted material. North Carolina is experiencing higher than anticipated rates of fatigue cracking compared to other state. These higher than expected rates could be reflective of the national trends in mix design practice or could be caused by structural pavement failures. The problems associated with premature cracking in North Carolina pavements point to the need to evaluate the North Carolina Department of Transportation (NCDOT) mixes, processes, and measures to ensure that these factors properly balance the goals of preventing cracking and minimizing permanent deformation. Without solid data from in-service pavements, any conclusions regarding the causes of these failures might be pure conjecture. Accordingly, this research examines material properties through laboratory experiments using field-extracted materials and investigates in situ pavements and pavement structure. In order to assess condition of existing pavement, alligator cracking index (ACI) was developed. The asphalt content in the top layer that exhibits top-down cracking or bottom-up cracking has a proportional relationship to ACI values. The air void content in a bottom layer that exhibits top-down cracking or bottom-up cracking shows an inverse proportional relationship to ACI values. These observations reflect reasonable results. A comparison between ACI and asphalt film thickness values does not produce noteworthy findings, but somewhat reasonable results are evident once the range of comparison is narrowed down. Thicker film thicknesses show higher ACI values. From field core visual observations, road widening is identified as a major cause of longitudinal cracking. Regions with observed layer interface separation tend to have low ACI values. Through tensile strain simulation based on actual field conditions, it is observed that

  19. Advanced Constitutive Modeling of Plain and Reinforced Concretes

    DTIC Science & Technology

    1988-12-31

    plastic models. Plain concrete, on the other hand. is one of the most complex structural materials in current use and, despite numerous efforts in...influence of basic material and geometric properties on damage accumulation and failure conditions. Under Tasks 1 and 2. a new, advanced model of...purpose of this study was to ascertain the influence of fundamental material , interface, and 4 0Ill l lll l * geometric properties on the nonlinear

  20. Cause Analysis on the Void under Slabs of Cement Concrete Pavement

    NASA Astrophysics Data System (ADS)

    Wen, Li; Zhu, Guo Xin; Baozhu

    2017-06-01

    This paper made a systematic analysis on the influence of the construction, environment, water and loads on the void beneath road slabs, and also introduced the formation process of structural void and pumping void, and summarizes the deep reasons for the bottom of the cement concrete pavement. Based on the analysis above, this paper has found out the evolution law of the void under slabs which claimed that the void usually appeared in the slab corners and then the cross joint, resulting void in the four sides with the void area under the front slab larger than the rear one.

  1. Noise characteristics of hot mix asphalt and Portland cement concrete pavements in United States

    NASA Astrophysics Data System (ADS)

    Hanson, Douglas I.

    2005-09-01

    In today's society, traffic noise is a serious problem that generally is considered an environmental pollution because it lowers the standard of living. Research in Europe and in the United States has indicated that it is possible to build pavement surfaces that will reduce the level of noise generated on roadways. In January of 2002 the National Center for Asphalt Technology initiated a research study with the objective to develop safe, quiet and durable asphalt pavement surfaces. As a part of that study over 300 pavement surfaces [both Portland Cement Concrete (PCCP) and Hot Mix Asphalt (HMA)] throughout the United States have been tested using a close-proximity noise trailer. The study has shown that in general PCCP surfaces have a higher noise level than HMA surfaces. But, it has also shown that by properly choosing the surface texture of the PCCP surface significant reductions in the noise level of a PCCP surface can be achieved. The study has shown that it is possible to construct low-noise HMA mixes and that in general the smaller the nominal maximum size for those mixes (regards whether they are dense graded, SMA or OFGC mixes) the lower the noise level.

  2. Enhancement of concrete properties for pavement slabs using waste metal drillings and silica fume.

    PubMed

    Hassani, Abolfazl; Arjmandi, Mohsen

    2010-01-01

    This paper presents a comparative study on the effects of steel fibres and waste metal drillings on the mechanical/physical behaviour of conventional and silica fume concrete. The amount of silica fume used was 10% of cement by mass and the amount of steel fibres and metal drillings used in both concrete mixtures was 0.5% by concrete volume for steel fibres and 0.0, 0.25, 0.50 and 0.75% for metal drillings, respectively. In total, 10 different mixtures were made and tested for compressive strength, modulus of elasticity, flexural strength and toughness. Our data reveal the significant impact of the effect of silica fume, steel fibres and industrial waste metal drillings on the mechanical and physical characteristics of concrete mixtures. The results also show that mixtures with steel fibres and waste metal drillings have comparable behaviour. Hence, there is a potential for use of waste metal drillings as an alternative to steel fibres for specific cases such as concrete pavement slabs.

  3. Performance-based and condition-based NDT for predicting maintenance needs of concrete highways and airport pavements

    NASA Astrophysics Data System (ADS)

    Hertlein, Bernhard H.; Davis, Allen G.

    1996-11-01

    The state-of-the-art for nondestructive testing (NDT) of highway and airport pavements was evaluated in the late 1980's as part of the Strategic Highway Rehabilitation Program (SHRP). This program included many research projects in pavement construction, testing, maintenance, and rehabilitation. The limitations, as well was the capabilities of the various NDT methods then extant were examined by joint teams of federal, state, academic, and private sector engineers and researchers. The SHRP program, and the allied long-term pavement performance program clearly demonstrated that certain NDT methods performed well on asphalt pavement but performed unsatisfactorily on concrete pavements, and vice-versa. Despite this, some methods are still being used inappropriately, while other promising techniques are virtually being ignored. This paper examines some of the reasons for this, and summarizes the research and current state-of-the-art for NDT of concrete airport and highway pavements. Promising avenues for further development of test equipment, applications, data analysis, and interpretation are also discussed.

  4. Precast Slab Literature Review Report: Repair of Rigid Airfield Pavements Using Precast Concrete Panels - A State-of-the-Art Review

    DTIC Science & Technology

    2010-06-01

    pp. 447-483. 22. Engineering Technical Letter (ETL) 97-2 (Change 1), Maintenance and Repair of Rigid Airfield Pavement Surfaces, Joints, and Cracks ...Joints, and Cracks . This ETL provides guidance for full-depth repairs of rigid airfield pavement surfaces using a cast-in-place method, but is also...AFRL-RX-TY-TR-2009-4588 PRECAST SLAB LITERATURE REVIEW REPORT: REPAIR OF RIGID AIRFIELD PAVEMENTS USING PRECAST CONCRETE PANELS—A STATE-OF

  5. 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.

  6. Laboratory analysis of the infiltration capacity of interlocking concrete block pavements in car parks.

    PubMed

    Sañudo-Fontaneda, Luis A; Rodriguez-Hernandez, Jorge; Vega-Zamanillo, Angel; Castro-Fresno, Daniel

    2013-01-01

    Interlocking concrete block pavements (ICBPs) have been widely used in car parks to reduce runoff. Researches have demonstrated that clogging is the most influential factor in the reduction of the infiltration capacity of this type of permeable pavement. Nevertheless, there is no laboratory study of the infiltration performance of ICBPs that combines clogging levels with variables related with the topography of car parks such as runoff surface length (R(SL)) and surface slope (S(S)). This paper studies the infiltration behaviour of ICBP during their operational life in a car park using an improved version of the Cantabrian Fixed (CF) Infiltrometer. This laboratory device simulates direct rainfall and runoff from adjacent impervious areas over an ICBPs surface of 0.25 m(2) for different slopes (0, 3, 5, 7 and 10%) and three scenarios of clogging (surface newly built, surface clogged and surface clogged with maintenance). This paper presents the results of the tests and a statistical analysis based on three regression models (corresponding to each clogging scenario) depending on the R(SL) and S(S) variables. All models passed a confidence level of 95%, presenting high R(2) values and showing that R(SL) is a more influential variable than the S(S) for all clogging scenarios.

  7. Probabilistic Flexural Fatigue in Plain and Fiber-Reinforced Concrete.

    PubMed

    Ríos, José D; Cifuentes, Héctor; Yu, Rena C; Ruiz, Gonzalo

    2017-07-07

    The objective of this work is two-fold. First, we attempt to fit the experimental data on the flexural fatigue of plain and fiber-reinforced concrete with a probabilistic model (Saucedo, Yu, Medeiros, Zhang and Ruiz, Int. J. Fatigue, 2013, 48, 308-318). This model was validated for compressive fatigue at various loading frequencies, but not for flexural fatigue. Since the model is probabilistic, it is not necessarily related to the specific mechanism of fatigue damage, but rather generically explains the fatigue distribution in concrete (plain or reinforced with fibers) for damage under compression, tension or flexion. In this work, more than 100 series of flexural fatigue tests in the literature are fit with excellent results. Since the distribution of monotonic tests was not available in the majority of cases, a two-step procedure is established to estimate the model parameters based solely on fatigue tests. The coefficient of regression was more than 0.90 except for particular cases where not all tests were strictly performed under the same loading conditions, which confirms the applicability of the model to flexural fatigue data analysis. Moreover, the model parameters are closely related to fatigue performance, which demonstrates the predictive capacity of the model. For instance, the scale parameter is related to flexural strength, which improves with the addition of fibers. Similarly, fiber increases the scattering of fatigue life, which is reflected by the decreasing shape parameter.

  8. Probabilistic Flexural Fatigue in Plain and Fiber-Reinforced Concrete

    PubMed Central

    Ríos, José D.

    2017-01-01

    The objective of this work is two-fold. First, we attempt to fit the experimental data on the flexural fatigue of plain and fiber-reinforced concrete with a probabilistic model (Saucedo, Yu, Medeiros, Zhang and Ruiz, Int. J. Fatigue, 2013, 48, 308–318). This model was validated for compressive fatigue at various loading frequencies, but not for flexural fatigue. Since the model is probabilistic, it is not necessarily related to the specific mechanism of fatigue damage, but rather generically explains the fatigue distribution in concrete (plain or reinforced with fibers) for damage under compression, tension or flexion. In this work, more than 100 series of flexural fatigue tests in the literature are fit with excellent results. Since the distribution of monotonic tests was not available in the majority of cases, a two-step procedure is established to estimate the model parameters based solely on fatigue tests. The coefficient of regression was more than 0.90 except for particular cases where not all tests were strictly performed under the same loading conditions, which confirms the applicability of the model to flexural fatigue data analysis. Moreover, the model parameters are closely related to fatigue performance, which demonstrates the predictive capacity of the model. For instance, the scale parameter is related to flexural strength, which improves with the addition of fibers. Similarly, fiber increases the scattering of fatigue life, which is reflected by the decreasing shape parameter. PMID:28773123

  9. The interaction between concrete pavement and corrosion-induced copper runoff from buildings.

    PubMed

    Bahar, B; Herting, G; Wallinder, I Odnevall; Hakkila, K; Leygraf, C; Virta, M

    2008-05-01

    Changes in chemical speciation of copper and the capacity of concrete pavement to retain copper in runoff water from external buildings have been investigated at urban field conditions, and in parallel laboratory experiments simulating outdoor scenarios. The research study showed the concrete surface to form a copper rich surface layer ( approximately 50 microm thick) upon exposure, and a high capacity to significantly reduce the bioavailable fraction of released copper (20-95%). The retention capacity of copper varied between 5 and 20% during single runoff events in the laboratory, and between 10 and 40% of the total copper release during single natural runoff events. The capacity to retain and reduce the bioavailable fraction of non-retained copper increased with increasing wetness of the concrete surfaces, increasing pH of the runoff water and decreasing flow rates. Bioassay testing with bacterial and yeast bioreporters showed the bioavailable fraction of non-retained copper to be significantly lower than the total copper concentration in the runoff water, between 22 and 40% for bacteria and between 8 and 31% for yeast. The application of generated data to simulate a fictive outdoor scenario, suggests a significant reduction of bioavailable and total copper to background values during environmental entry as a result of dilution, and the interaction with solid surfaces, organic matter and complexing agents already in the drainage system.

  10. Permeability measurement and scan imaging to assess clogging of pervious concrete pavements in parking lots.

    PubMed

    Kayhanian, Masoud; Anderson, Dane; Harvey, John T; Jones, David; Muhunthan, Balasingam

    2012-03-01

    This paper describes a study that used permeability measurement along with physical and hydrological characteristics of 20 pervious concrete pavements in parking lots throughout California. The permeability was measured at five locations: the main entrance, an area with no traffic, and three separate measurements within a parking space at each parking lot. Hydrological and physical site characteristics such as traffic flow, erosion, vegetation cover, sediments accumulation, maintenance practice, presence of cracking, rainfall, and temperature data were also collected for each parking lot. These data were used to perform detailed statistical analysis to determine factors influencing changes in permeability and hence assessing possible cause of clogging. In addition, seven representative core samples were obtained from four different parking lots with permeability ranging from very low to very high. Porosity profiles produced from CT scanning were used to assess the possible nature and extent of clogging. Results showed that there is a large variation in permeability within each parking lot and between different parking lots. In general, the age of the parking lot is the predominant factor influencing the permeability. Statistical analysis revealed that fine sediment (particles less than 38 μm) mass is also an important influencing factor. Other influencing factors with lower significance included number of days with a temperature greater than 30°C and the amount of vegetation next to the parking lot. The combined scanned image analysis and porosity profile of the cores showed that most clogging occurs near the surface of the pavement. While lower porosity generally appeared to be limited to the upper 25 mm, in some core samples evidence of lower porosity was found up to 100mm below the surface.

  11. About the sizes of elastomer particles in the asphalt concrete binder providing the maximum service life of pavements

    NASA Astrophysics Data System (ADS)

    Kaplan, A. M.; Chekunaev, N. I.

    2014-05-01

    It is noted that the durability of asphalt concrete pavements is determined by the time of the trunk cracks formation in the polymer-containing composites - in the modified by elastomers (e.g., by rubber) bitumenous binder of asphalt. Developed by the authors previously the theory of the cracks propagation in heterosystems [1] has allowed to investigate the problem of the cracks propagation in the rubber-bitumen composite. This investigations show that most effectively to prevente the trunk cracks formation in asphalt concrete can ultrafine rubber particles (150-750 nm) in a bitumenos binder of asphalt.

  12. Fatigue and Fracture Characterization of GlasGridRTM Reinforced Asphalt Concrete Pavement

    NASA Astrophysics Data System (ADS)

    Safavizadeh, Seyed Amirshayan

    The purpose of this research is to develop an experimental and analytical framework for describing, modeling, and predicting the reflective cracking patterns and crack growth rates in GlasGridRTM-reinforced asphalt pavements. In order to fulfill this objective, the effects of different interfacial conditions (mixture and tack coat type, and grid opening size) on reflective cracking-related failure mechanisms and the fatigue and fracture characteristics of fiberglass grid-reinforced asphalt concrete beams were studied by means of four- and threepoint bending notched beam fatigue tests (NBFTs) and cyclic and monotonic interface shear tests. The digital image correlation (DIC) technique was utilized for obtaining the displacement and strain contours of specimen surfaces during each test. The DIC analysis results were used to develop crack tip detection methods that were in turn used to determine interfacial crack lengths in the shear tests, and vertical and horizontal (interfacial) crack lengths in the notched beam fatigue tests. Linear elastic fracture mechanics (LEFM) principles were applied to the crack length data to describe the crack growth. In the case of the NBFTs, a finite element (FE) code was developed and used for modeling each beam at different stages of testing and back-calculating the stress intensity factors (SIFs) for the vertical and horizontal cracks. The local effect of reinforcement on the stiffness of the system at a vertical crack-interface intersection or the resistance of the grid system to the deflection differential at the joint/crack (hereinafter called joint stiffness) for GlasGrid-reinforced asphalt concrete beams was determined by implementing a joint stiffness parameter into the finite element code. The strain level dependency of the fatigue and fracture characteristics of the GlasGrid-reinforced beams was studied by performing four-point bending notched beam fatigue tests at strain levels of 600, 750, and 900 microstrain. These beam

  13. A study of sound absorption by street canyon boundaries and asphalt rubber concrete pavement

    NASA Astrophysics Data System (ADS)

    Drysdale, Graeme Robert

    A sound field model, based on a classical diffusion equation, is extended to account for sound absorption in a diffusion parameter used to model sound energy in a narrow street canyon. The model accounts for a single sound absorption coefficient, separate accommodation coefficients and a combination of separate absorption and accommodation coefficients from parallel canyon walls. The new expressions are compared to the original formula through numerical simulations to reveal the effect of absorption on sound diffusion. The newly established analytical formulae demonstrate satisfactory agreement with their predecessor under perfect reflection. As well, the influence of the extended diffusion parameter on normalized sound pressure levels in a narrow street canyon is in agreement with experimental data. The diffusion parameters are used to model sound energy density in a street canyon as a function of the sound absorption coefficient of the street canyon walls. The acoustic and material properties of conventional and asphalt rubber concrete (ARC) pavement are also studied to assess how the crumb rubber content influences sound absorption in street canyons. The porosity and absolute permeability of compacted specimens of asphalt rubber concrete are measured and compared to their normal and random incidence sound absorption coefficients as a function of crumb rubber content in the modified binder. Nonlinear trends are found between the sound absorption coefficients, porosity and absolute permeability of the compacted specimens and the percentage of crumb rubber in the modified binders. The cross-sectional areas of the air voids on the surfaces of the compacted specimens are measured using digital image processing techniques and a linear relationship is obtained between the average void area and crumb rubber content. The measured material properties are used to construct an empirical formula relating the average porosity, normal incidence noise reduction coefficients and

  14. 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.

  15. Minimum Thickness of Concrete Pavement for the F-15 and C-17 Aircraft

    DTIC Science & Technology

    2013-07-01

    for the design of military rigid airfield pavements contained in the Unified Facilities Criteria 3-260-02 gives the minimum thickness of airfield...Documentation Page ERDC/GSL TR-13-34 v Figures and Tables Figures Figure 1. Layout of the rigid pavement test section...necessary. The study herein provides data to justify the recommended changes in the minimum thickness values of rigid airfield pavements . Personnel of the

  16. Peridynamic modeling of plain and reinforced concrete structures.

    SciTech Connect

    Silling, Stewart Andrew; Gerstle, Walter H.; Sau, Nicolas

    2005-08-01

    The peridynamic model was introduced by Silling in 1998. In this paper, we demonstrate the application of the quasistatic peridynamic model to two-dimensional, linear elastic, plane stress and plane strain problems, with special attention to the modeling of plain and reinforced concrete structures. We consider just one deviation from linearity--that which arises due to the irreversible sudden breaking of bonds between particles. The peridynamic model starts with the assumption that Newton's second law holds true on every infinitesimally small free body (or particle) within the domain of analysis. A specified force density function, called the pairwise force function, (with units of force per unit volume per unit volume) between each pair of infinitesimally small particles is postulated to act if the particles are closer together than some finite distance, called the material horizon. The pairwise force function may be assumed to be a function of the relative position and the relative displacement between the two particles. In this paper, we assume that for two particles closer together than the specified 'material horizon' the pairwise force function increases linearly with respect to the stretch, but at some specified stretch, the pairwise force function is irreversibly reduced to zero.

  17. Investigation of Self Consolidating Concrete Containing High Volume of Supplementary Cementitious Materials and Recycled Asphalt Pavement Aggregates

    NASA Astrophysics Data System (ADS)

    Patibandla, Varun chowdary

    The use of sustainable technologies such as supplementary cementitiuous materials (SCMs), and/or recycled materials is expected to positively affect the performance of concrete mixtures. However, it is important to study and qualify such mixtures and check if the required specifications of their intended application are met before they can be implemented in practice. This study presents the results of a laboratory investigation of Self Consolidating concrete (SCC) containing sustainable technologies. A total of twelve concrete mixtures were prepared with various combinations of fly ash, slag, and recycled asphalt pavement (RAP). The mixtures were divided into three groups with constant water to cementitiuous materials ratio of 0.37, and based on the RAP content; 0, 25, and 50% of coarse aggregate replaced by RAP. All mixtures were prepared to achieve a target slump flow equal to or higher than 500 mm (24in). A control mixture for each group was prepared with 100% Portland cement whereas all other mixtures were designed to have up to 70% of portland cement replaced by a combination of supplementary cementitiuous materials (SCMs) such as class C fly ash and granulated blast furnace slag. The properties of fresh concrete investigated in this study include flowability, deformability; filling capacity, and resistance to segregation. In addition, the compressive strength at 3, 14, and 28 days, the tensile strength, and the unrestrained shrinkage up to 80 days was also investigated. As expected the inclusion of the sustainable technologies affected both fresh and hardened concrete properties. Analysis of the experimental data indicated that inclusion of RAP not only reduces the ultimate strength, but it also affected the compressive strength development rate. Moreover, several mixes satisfied compressive strength requirements for pavements and bridges; those mixes included relatively high percentages of SCMs and RAP. Based on the results obtained in this study, it is not

  18. Thickness and air voids measurement on asphalt concrete pavements using ground-penetrating radar

    NASA Astrophysics Data System (ADS)

    Dhakal, Sharad Raj

    Layer thickness and air voids are important parameters in quality assurance of newly paved hot mix asphalt (HMA) pavements. A non-destructive testing (NDT) technique was used to collect layer thickness information. The thicknesses estimated by the technique were compared with core thicknesses. Ground penetrating radar (GPR) system with air coupled antennas was used for on-site pavement data collection. Two application softwares - RADAN and ROAD DOCTOR - were used to process the field data for estimating layer thicknesses and air voids along the scanned pavements. 150 mm diameter cores taken from random locations on the pavements were tested in the laboratory to determine layer thickness and air voids. Statistical analyses were conducted to compare thicknesses and generate a regression equation relating air voids and dielectric constant of the pavement material. No significant differences were found between thickness estimates from RADAN and ROAD DOCTOR softwares when compared to the core measurements. However, RADAN and ROAD DOCTOR results are marginally significantly different from each other. ROAD DOCTOR software was used to generate air voids for the pavements scanned. Laboratory results from cores were utilized to determine calibration factors for the air voids -- dielectric equation. A relationship between air voids and dielectric constant is presented. It is concluded that GPR system with air coupled antennas used alongside a reduced core testing has a potential for quality control of newly paved hot mixed asphalt pavements.

  19. Asphalt additives in thick hot mixed asphalt-concrete pavements. Research report (Interim), Sep 86-Oct 90

    SciTech Connect

    Button, J.W.; Prapnnachari, S.

    1991-01-01

    Asphalt concrete field test pavements were placed in District 19 north of Texarkana on US-59/71 in 1987 and 1988 to evaluate the ability of certain asphalt additives to enhance resistance to cracking and rutting. Two 10-inch thick and 0.9 mile (approx.) long test pavements and a similar untreated control section were constructed in the northbound and southbound lanes for a total of 6 field trials. Asphalt additives were incorporated in both the 8-inch base and the overlying 2-inch surface layers. The additives evaluated included Goodyear LPF 5812, Chemkrete-CTI 102, Exxon Polybilt 102, and Styrelf 13. Samples of paving materials including aggregates, asphalts, compacted mixes, and pavement cores were collected, conveyed to the laboratory, and tested to provide detailed documentation of their properties. Tests included rheological properties of the binders before and after artificial aging, characterization of aggregate, Hveem and Marshall stability, stiffness as a function of temperature, tensile properties before and after moisture conditioning and artificial aging, air void content, creep, and permanent deformation. Field tests and visual evaluations have been conducted to objectively evaluate field performance. Results of these tests are reported herein. Within 6 months after construction of the base layers and prior to placement of the surface course, the Chemkrete modified base became severely cracked. As a result, the surface mix placed on this base section was treated with Goodyear latex rather than Chemkrete. All other modified pavements and the control section have performed well and exhibited essentially equivalent performance after 2 1/2 years in service.

  20. Fracture Behavior and Properties of Functionally Graded Fiber-Reinforced Concrete

    NASA Astrophysics Data System (ADS)

    Roesler, Jeffery; Bordelon, Amanda; Gaedicke, Cristian; Park, Kyoungsoo; Paulino, Glaucio

    2008-02-01

    In concrete pavements, a single concrete mixture design is selected to resist mechanical loading without attempting to adversely affect the concrete pavement shrinkage, ride quality, or noise attenuation. An alternative approach is to design distinct layers within the concrete pavement surface which have specific functions thus achieving higher performance at a lower cost. The objective of this research was to address the structural benefits of functionally graded concrete materials (FGCM) for rigid pavements by testing and modeling the fracture behavior of different combinations of layered plain and synthetic fiber-reinforced concrete materials. Fracture parameters and the post-peak softening behavior were obtained for each FGCM beam configuration by the three point bending beam test. The peak loads and initial fracture energy between the plain, fiber-reinforced, and FGCM signified similar crack initiation. The total fracture energy indicated improvements in fracture behavior of FGCM relative to full-depth plain concrete. The fracture behavior of FGCM depended on the position of the fiber-reinforced layer relative to the starter notch. The fracture parameters of both fiber-reinforced and plain concrete were embedded into a finite element-based cohesive zone model. The model successfully captured the experimental behavior of the FGCMs and predicted the fracture behavior of proposed FGCM configurations and structures. This integrated approach (testing and modeling) demonstrates the viability of FGCM for designing layered concrete pavements system.

  1. Fracture Behavior and Properties of Functionally Graded Fiber-Reinforced Concrete

    SciTech Connect

    Roesler, Jeffery; Bordelon, Amanda; Gaedicke, Cristian; Park, Kyoungsoo; Paulino, Glaucio

    2008-02-15

    In concrete pavements, a single concrete mixture design is selected to resist mechanical loading without attempting to adversely affect the concrete pavement shrinkage, ride quality, or noise attenuation. An alternative approach is to design distinct layers within the concrete pavement surface which have specific functions thus achieving higher performance at a lower cost. The objective of this research was to address the structural benefits of functionally graded concrete materials (FGCM) for rigid pavements by testing and modeling the fracture behavior of different combinations of layered plain and synthetic fiber-reinforced concrete materials. Fracture parameters and the post-peak softening behavior were obtained for each FGCM beam configuration by the three point bending beam test. The peak loads and initial fracture energy between the plain, fiber-reinforced, and FGCM signified similar crack initiation. The total fracture energy indicated improvements in fracture behavior of FGCM relative to full-depth plain concrete. The fracture behavior of FGCM depended on the position of the fiber-reinforced layer relative to the starter notch. The fracture parameters of both fiber-reinforced and plain concrete were embedded into a finite element-based cohesive zone model. The model successfully captured the experimental behavior of the FGCMs and predicted the fracture behavior of proposed FGCM configurations and structures. This integrated approach (testing and modeling) demonstrates the viability of FGCM for designing layered concrete pavements system.

  2. Pavement evaluation and rehabilitation

    SciTech Connect

    Ali, N.A.; Khosla, N.P.; Johnson, E.G.; Hicks, R.G.; Uzan, J.

    1987-01-01

    The 20 papers in this report deal with the following areas: determination of layer moduli using a falling weight deflectometer; evaluation of effect of uncrushed base layers on pavement performance; the effect of contact area shape and pressure distribution on multilayer systems response; sensitivity analysis of selected backcalculation procedures; performance of a full-scale pavement design experiment in Jamaica; subsealing and load-transfer restoration; development of a demonstration prototype expert system for concrete pavement evaluation; numerical assessment of pavement test sections; development of a distress index and rehabilitation criteria for continuously reinforced concrete pavements using discriminant analysis; a mechanistic model for thermally induced reflection cracking of portland cement concrete pavement with reinforced asphalt concrete overlay; New Mexico study of interlayers used in reflective crack control; status of the South Dakota profilometer; incorporating the effects of tread pattern in a dynamic tire excitation mechanism; external methods for evaluating shock absorbers for road-roughness measurements; factor analysis of pavement distresses for surface condition predictions; development of a utility evaluation for nondestructive-testing equipment used on asphalt-concrete pavements; estimating the life of asphalt overlays using long-term pavement performance data; present serviceability-roughness correlations using rating panel data; video image distress analysis technique for Idaho transportation department pavement-management system; acceptability of shock absorbers for road roughness-measuring trailers.

  3. Cathodoluminescence microscopy and petrographic image analysis of aggregates in concrete pavements affected by alkali-silica reaction

    SciTech Connect

    Stastna, A.; Sachlova, S.; Pertold, Z.; Prikryl, R.; Leichmann, J.

    2012-03-15

    Various microscopic techniques (cathodoluminescence, polarizing and electron microscopy) were combined with image analysis with the aim to determine a) the modal composition and degradation features within concrete, and b) the petrographic characteristics and the geological types (rocks, and their provenance) of the aggregates. Concrete samples were taken from five different portions of Highway Nos. D1, D11, and D5 (the Czech Republic). Coarse and fine aggregates were found to be primarily composed of volcanic, plutonic, metamorphic and sedimentary rocks, as well as of quartz and feldspar aggregates of variable origins. The alkali-silica reaction was observed to be the main degradation mechanism, based upon the presence of microcracks and alkali-silica gels in the concrete. Use of cathodoluminescence enabled the identification of the source materials of the quartz aggregates, based upon their CL characteristics (i.e., color, intensity, microfractures, deformation, and zoning), which is difficult to distinguish only employing polarizing and electron microscopy. - Highlights: Black-Right-Pointing-Pointer ASR in concrete pavements on the Highways Nos. D1, D5 and D11 (Czech Republic). Black-Right-Pointing-Pointer Cathodoluminescence was combined with various microscopic techniques and image analysis. Black-Right-Pointing-Pointer ASR was attributed to aggregates. Black-Right-Pointing-Pointer Source materials of aggregates were identified based on cathodoluminescence characteristics. Black-Right-Pointing-Pointer Quartz comes from different volcanic, plutonic and metamorphic parent rocks.

  4. Strain distribution and crack detection in thin unbonded concrete pavement overlays with fully distributed fiber optic sensors

    NASA Astrophysics Data System (ADS)

    Bao, Yi; Chen, Genda

    2016-01-01

    This study aims at evaluating the feasibility of strain measurement and crack detection in thin unbonded concrete pavement overlays with pulse prepump Brillouin optical time domain analysis. Single-mode optical fibers with two-layer and three-layer coatings, respectively, were applied as fully distributed sensors, their performances were compared with analytical predictions. They were successfully protected from damage during concrete casting of three full-scale concrete panels when 5 to 10-cm-thick protective mortar covers had been set for 2 h. Experimental results from three-point loading tests of the panels indicated that the strain distributions measured from the two types of sensors were in good agreement, and cracks can be detected at sharp peaks of the measured strain distributions. The two-layer and three-layer coated fibers can be used to measure strains up to 2.33% and 2.42% with a corresponding sensitivity of 5.43×10-5 and 4.66×10-5 GHz/μɛ, respectively. Two cracks as close as 7 to 9 cm can be clearly detected. The measured strains in optical fiber were lower than the analytical prediction by 10% to 25%. Their difference likely resulted from strain transfer through various coatings, idealized point loading, varying optical fiber embedment, and concrete heterogeneity.

  5. Environmental performance and mechanical analysis of concrete containing recycled asphalt pavement (RAP) and waste precast concrete as aggregate.

    PubMed

    Erdem, Savaş; Blankson, Marva Angela

    2014-01-15

    The overall objective of this research project was to investigate the feasibility of incorporating 100% recycled aggregates, either waste precast concrete or waste asphalt planning, as replacements for virgin aggregates in structural concrete and to determine the mechanical and environmental performance of concrete containing these aggregates. Four different types of concrete mixtures were designed with the same total water cement ratio (w/c=0.74) either by using natural aggregate as reference or by totally replacing the natural aggregate with recycled material. Ground granulated blast furnace slag (GGBS) was used as a mineral addition (35%) in all mixtures. The test results showed that it is possible to obtain satisfactory performance for strength characteristics of concrete containing recycled aggregates, if these aggregates are sourced from old precast concrete. However, from the perspective of the mechanical properties, the test results indicated that concrete with RAP aggregate cannot be used for structural applications. In terms of leaching, the results also showed that the environmental behaviour of the recycled aggregate concrete is similar to that of the natural aggregate concrete.

  6. Adaptive Crack Modeling with Interface Solid Elements for Plain and Fiber Reinforced Concrete Structures

    PubMed Central

    Zhan, Yijian

    2017-01-01

    The effective analysis of the nonlinear behavior of cement-based engineering structures not only demands physically-reliable models, but also computationally-efficient algorithms. Based on a continuum interface element formulation that is suitable to capture complex cracking phenomena in concrete materials and structures, an adaptive mesh processing technique is proposed for computational simulations of plain and fiber-reinforced concrete structures to progressively disintegrate the initial finite element mesh and to add degenerated solid elements into the interfacial gaps. In comparison with the implementation where the entire mesh is processed prior to the computation, the proposed adaptive cracking model allows simulating the failure behavior of plain and fiber-reinforced concrete structures with remarkably reduced computational expense. PMID:28773130

  7. Adaptive Crack Modeling with Interface Solid Elements for Plain and Fiber Reinforced Concrete Structures.

    PubMed

    Zhan, Yijian; Meschke, Günther

    2017-07-08

    The effective analysis of the nonlinear behavior of cement-based engineering structures not only demands physically-reliable models, but also computationally-efficient algorithms. Based on a continuum interface element formulation that is suitable to capture complex cracking phenomena in concrete materials and structures, an adaptive mesh processing technique is proposed for computational simulations of plain and fiber-reinforced concrete structures to progressively disintegrate the initial finite element mesh and to add degenerated solid elements into the interfacial gaps. In comparison with the implementation where the entire mesh is processed prior to the computation, the proposed adaptive cracking model allows simulating the failure behavior of plain and fiber-reinforced concrete structures with remarkably reduced computational expense.

  8. Behavior of Plain Concrete of a High Water-Cement Ratio after Freeze-Thaw Cycles

    PubMed Central

    Shang, Huai-Shuai; Yi, Ting-Hua; Song, Yu-Pu

    2012-01-01

    An experimental study of plain concrete specimens of water-cement ratio 0.55, subjected to 0, 15, 25, 40, 50 and 75 cycles of freeze-thaw was completed. The dynamic modulus of elasticity (DME), weight loss, compressive strength, tensile strength, flexural strength, cleavage strength and stress-strain relationships of plain concrete specimens suffering from freeze-thaw cycles were measured. The experimental results showed that the strength decreased as the freeze-thaw cycles were repeated. A concise mathematic formula between DME, weight loss, mechanical properties and number of freeze-thaw cycles was also established. The influences of freeze-thaw cycles on the DME, weight loss and mechanical properties were analyzed. The experimental results serve as a reference for the maintenance, design and life prediction of dams, hydraulic structures, offshore structures, concrete roads and bridges in cold regions.

  9. A Comparative Field Study of Permastripe(Trademark) Polymer Concrete and Waterborne Airfield Pavement Markings

    DTIC Science & Technology

    2007-06-01

    readily removable from asphalt pavement using water-blasting, and some test lines suffered from soiling by algal/ mildew growth. The data clearly show...of cement. Under these conditions, consistent viscosity cannot be achieved. Viscosity control is absolutely essential to controlling spray...investigations revealed that mildew or algae were the likely source. Apparently, the porous nature of Permastripe™ allows for moisture to be trapped

  10. Recycling of Portland Cement Concrete Airport Pavements - A State-of-the-Art Study,

    DTIC Science & Technology

    1981-04-01

    Urban Roads, Mar 1980, pp 70-71. 2. Waterways Experiment Station. Miscellaneous Paper C-72-14: Recycled Concrete, by A. D. Buck. Vicksburg, Miss., May...1972. 3. . Miscellaneous Paper C-72-14 (Report 2): Recycled Concrete - Additional Investigations, by A. D. Buck. Vicksburg, Miss., Apr 1976. 4...Miscellaneous Paper C-76-2: Recycled Concrete as a Source of Aggregate, by A. D. Buck. Vicksburg, Miss., Apr 1976. ! " . Institute of Technology (IOef 5

  11. Development of Advanced Constitutive Models for Plain and Reinforced Concrete.

    DTIC Science & Technology

    1985-04-08

    1473, 83 APR EOITION OP T JAN 73 IS OBSOLETE. U.nclassified SECURITY CLASSIFICATION OF 7THIS PAGE TABLE OF CONTENTS SECTI ON PAGE FOREWORD...the older theory used to develop the concrete models described by Bazant and Bhat (24 ) and Bazant and Shieh. (25 ) Proper closure of hysteresis loops...is guaranteed in the present theory, so that artifices, such as the jump-kinematic hardening introduced by Bazant and Shieh, (25 ) are not required

  12. Pavement base drain evaluation

    NASA Astrophysics Data System (ADS)

    Hoffman, G. L.

    1981-06-01

    Portions of a highway drainage system design was revised. Essentially, the longitudinal drainage trench was moved closer to the pavement/shoulder joint, and the fine concrete sand layer was eliminated as a trench backfill material. The specified backfill material is a coarser crushed aggregate (pea gravel). An evaluation of the effects of these changes on pavement performance is given and the new pavement base drain system is compared to the older pipe foundation underdrain system at the same site.

  13. Development of Advanced Constitutive Models for Plain and Reinforced Concrete.

    DTIC Science & Technology

    1986-04-01

    Concrete,"’ Mechanics of MateriaLs, 3 (1984), 271. 2. Read, H. E., Discussion of "Hysteretic Endochronic Theory for Sand," by Z. P. Bazant , R. J. Krizek and...C.-L. Shieh, Journa L of Engineering Mechanics, Vol. III(1), Jan . 1985, 103. 3. Hegemier, G. A., H. Murakami, and L. J. Hageman, "On Tension...T ’ TM ’’ -x ’ ’"- REFERENCES Bazant , Z. P., and L. Cedolin (1979), "Blunt Crack Propagation in Finite Element Analysis," J. Engr. Mechs. Div., ASCE

  14. Shrinkage-Compensating Cement for Airport Pavement. Phase 3. Fibrous Concretes. Addendum.

    DTIC Science & Technology

    1980-09-01

    and then tested in accordance with ASTh C39-72 for compressive strength and ASTh C78-75 for flexural strength. Curing Following final set, the slab...Keeton, Port Hueneme, Calif., Nov 1977. ASTM STANDARDS CITED 1. ASTM C33-78, "Standard Specification for Concrete Aggregates." 2. ASTh C618-78, "Standard...Content of Freshly Mixed Concrete by the Pressure Method." 4. ASTh C39-72, "Test for Compressive Strength of Cylindrical Concrete Specimens." 5. ASTM C78

  15. Pervious Pavement System Evaluation

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, grade...

  16. Pervious Pavement System Evaluation

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, grade...

  17. Permeability predictions for sand-clogged Portland cement pervious concrete pavement systems.

    PubMed

    Haselbach, Liv M; Valavala, Srinivas; Montes, Felipe

    2006-10-01

    Pervious concrete is an alternative paving surface that can be used to reduce the nonpoint source pollution effects of stormwater runoff from paved surfaces such as roadways and parking lots by allowing some of the rainfall to permeate into the ground below. This infiltration rate may be adversely affected by clogging of the system, particularly clogging or covering by sand in coastal areas. A theoretical relation was developed between the effective permeability of a sand-clogged pervious concrete block, the permeability of sand, and the porosity of the unclogged block. Permeabilities were then measured for Portland cement pervious concrete systems fully covered with extra fine sand in a flume using simulated rainfalls. The experimental results correlated well with the theoretical calculated permeability of the pervious concrete system for pervious concrete systems fully covered on the surface with sand. Two different slopes (2% and 10%) were used. Rainfall rates were simulated for the combination of direct rainfall (passive runoff) and for additional stormwater runoff from adjacent areas (active runoff). A typical pervious concrete block will allow water to pass through at flow rates greater than 0.2 cm/s and a typical extra fine sand will have a permeability of approximately 0.02 cm/s. The limit of the system with complete sand coverage resulted in an effective system permeability of approximately 0.004 cm/s which is similar to the rainfall intensity of a 30 min duration, 100-year frequency event in the southeastern United States. The results obtained are important in designing and evaluating pervious concrete as a paving surface within watershed management systems for controlling the quantity of runoff.

  18. The influence of plain bar on bond strength of geopolymer concrete

    NASA Astrophysics Data System (ADS)

    Dewi, Evrianti Syntia; Ekaputri, Januarti Jaya

    2017-06-01

    This paper presents some results of experimental study of bond strength of plain bar embedded in geopolymer concrete. Fly ash class F was used as a raw material activated with alkali solutions. The combination of 8 Molar of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) as alkali activators was examined in the mixture with ratio of 2.5 by weight. Nine cubical specimens with a size of 150 × 150 × 150 mm were prepared to measure bond strength and slip between reinforcement and concrete. The influential factors studied for the experimental investigation were the diameter of reinforcement bar, bond area, and concrete cover to diameter (c/d) of reinforcement. The result showed that the average bond strength decreased as the diameter of plain bar and bonded length were increased from 16 mm to 19 mm. However, the 12 mm showed the different result allegedly caused by the effect of bond area and the passive confined provided by the concrete. Based on several equations used to compare the bond strength, it is clear that deformed bar of 12 mm in diameter is potential to increase the bond strength.

  19. An Evaluation and Proposal of United States Air Force Uses of Roller Compacted Concrete Pavement.

    DTIC Science & Technology

    1986-09-01

    8217., . ....." -’, " *,, " . . ". - -*-. "’. % ’- - II. Literature Review Overview Authors take two general approaches to the subject of Roller Compacted Concrete ...II. Literature Reveiw .... ............. 7 Overview 7..............7 Definition of RCCP ............. 7 Functional Review ...... ............ 8...47 Overview .................................... 47 Research Objectives: I. Advantages and Disadvantages of RCCP

  20. Pervious Pavement System Evaluation-Poster

    EPA Science Inventory

    Pervious pavement is a low impact development stormwater control. The Environmental Protection Agency's Urban Watershed Management Branch is evaluating interlocking concrete pavingstone pervious pavement systems. The pavingstones themselves are impermeable, but the spaces between...

  1. Infiltration and Evaporation of Diesel and Gasoline Droplets Spilled onto Concrete Pavement

    NASA Astrophysics Data System (ADS)

    Hilpert, M.; Adria-Mora, B.

    2015-12-01

    Pollution at gas stations due to small spills that occur during refueling of customer vehicles has received little attention. We have performed laboratory experiments in order to assess the processes of evaporation and infiltration of fuel spilled onto concrete samples. Changes in mass of both spilled diesel and gasoline droplets as a function of time have been analyzed. The infiltrated mass is affected by variations in humidity, among other parameters, which influence the amount of water condensed onto the concrete. Therefore, we used a humidity data logger and statistical tools to predict the evolution of the real mass of infiltrated fuel. The infiltrated mass roughly decreases exponentially, but the difference in behavior between both fuel types is important. The percentage of evaporated mass is much larger for gasoline, while infiltration is more significant for diesel. Also, the percentage of infiltrated liquid depends on the initial droplet mass. We also developed a multiphysics model, which couples pore-scale infiltration to turbulent atmospheric transport, to explain the experimental data. In conclusion, a substantial amount of fuel could both seep into the ground to contaminate groundwater and be released to the atmosphere. More studies are needed to quantify the public health implications of the released pollutants.

  2. Evaluation of a Dust Control for a Small Slab-Riding Dowel Drill for Concrete Pavement

    PubMed Central

    Echt, Alan; Mead, Kenneth

    2016-01-01

    Purpose To assess the effectiveness of local exhaust ventilation to control respirable crystalline silica exposures to acceptable levels during concrete dowel drilling. Approach Personal breathing zone samples for respirable dust and crystalline silica were collected while laborers drilled holes 3.5 cm diameter by 36 cm deep in a concrete slab using a single-drill slab-riding dowel drill equipped with local exhaust ventilation. Data were collected on air flow, weather, and productivity. Results All respirable dust samples were below the 90 µg detection limit which, when combined with the largest sample volume, resulted in a minimum detectable concentration of 0.31 mg m−3. This occurred in a 32-min sample collected when 27 holes were drilled. Quartz was only detected in one air sample; 0.09 mg m−3 of quartz was found on an 8-min sample collected during a drill maintenance task. The minimum detectable concentration for quartz in personal air samples collected while drilling was performed was 0.02 mg m−3. The average number of holes drilled during each drilling sample was 23. Over the course of the 2-day study, air flow measured at the dust collector decreased from 2.2 to 1.7 m3 s−1. Conclusions The dust control performed well under the conditions of this test. The initial duct velocity with a clean filter was sufficient to prevent settling, but gradually fell below the recommended value to prevent dust from settling in the duct. The practice of raising the drill between each hole may have prevented the dust from settling in the duct. A slightly higher flow rate and an improved duct design would prevent settling without regard to the position of the drill. PMID:26826033

  3. Evaluation of a Dust Control for a Small Slab-Riding Dowel Drill for Concrete Pavement.

    PubMed

    Echt, Alan; Mead, Kenneth

    2016-05-01

    To assess the effectiveness of local exhaust ventilation to control respirable crystalline silica exposures to acceptable levels during concrete dowel drilling. Personal breathing zone samples for respirable dust and crystalline silica were collected while laborers drilled holes 3.5 cm diameter by 36 cm deep in a concrete slab using a single-drill slab-riding dowel drill equipped with local exhaust ventilation. Data were collected on air flow, weather, and productivity. All respirable dust samples were below the 90 µg detection limit which, when combined with the largest sample volume, resulted in a minimum detectable concentration of 0.31 mg m(-3). This occurred in a 32-min sample collected when 27 holes were drilled. Quartz was only detected in one air sample; 0.09 mg m(-3) of quartz was found on an 8-min sample collected during a drill maintenance task. The minimum detectable concentration for quartz in personal air samples collected while drilling was performed was 0.02 mg m(-3). The average number of holes drilled during each drilling sample was 23. Over the course of the 2-day study, air flow measured at the dust collector decreased from 2.2 to 1.7 m(3) s(-1). The dust control performed well under the conditions of this test. The initial duct velocity with a clean filter was sufficient to prevent settling, but gradually fell below the recommended value to prevent dust from settling in the duct. The practice of raising the drill between each hole may have prevented the dust from settling in the duct. A slightly higher flow rate and an improved duct design would prevent settling without regard to the position of the drill. Published by Oxford University Press on behalf of the British Occupational Hygiene Society 2016.

  4. Mechanical and Permeability Characteristics of Latex-Modified Pre-Packed Pavement Repair Concrete as a Function of the Rapid-Set Binder Content

    PubMed Central

    Han, Jae-Woong; Jeon, Ji-Hong; Park, Chan-Gi

    2015-01-01

    We evaluated the strength and durability characteristics of latex-polymer-modified, pre-packed pavement repair concrete (LMPPRC) with a rapid-set binder. The rapid-set binder was a mixture of rapid-set cement and silica sand, where the fluidity was controlled using a latex polymer. The resulting mix exhibited a compressive strength of ≥21 MPa and a flexural strength of ≥3.5 MPa after 4 h of curing (i.e., the traffic opening term for emergency repairs of pavement). The ratio of latex polymer to rapid-set binder material was varied through 0.40, 0.33, 0.29, and 0.25. Mechanical characterization revealed that the mechanical performance, permeability, and impact resistance increased as the ratio of latex polymer to rapid-set binder decreased. The mixture exhibited a compressive strength of ≥21 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ≤0.29. The mixture exhibited a flexural strength of ≥3.5 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ≤0.33. The permeability resistance to chloride ions satisfied 2000 C after 7 days of curing for all ratios. The ratio of latex polymer to rapid-set binder material that satisfied all conditions for emergency pavement repair was ≤0.29. PMID:28793596

  5. Mechanical and Permeability Characteristics of Latex-Modified Pre-Packed Pavement Repair Concrete as a Function of the Rapid-Set Binder Content.

    PubMed

    Han, Jae-Woong; Jeon, Ji-Hong; Park, Chan-Gi

    2015-10-01

    We evaluated the strength and durability characteristics of latex-polymer-modified, pre-packed pavement repair concrete (LMPPRC) with a rapid-set binder. The rapid-set binder was a mixture of rapid-set cement and silica sand, where the fluidity was controlled using a latex polymer. The resulting mix exhibited a compressive strength of ¥21 MPa and a flexural strength of ¥3.5 MPa after 4 h of curing (i.e., the traffic opening term for emergency repairs of pavement). The ratio of latex polymer to rapid-set binder material was varied through 0.40, 0.33, 0.29, and 0.25. Mechanical characterization revealed that the mechanical performance, permeability, and impact resistance increased as the ratio of latex polymer to rapid-set binder decreased. The mixture exhibited a compressive strength of ¥21 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ¤0.29. The mixture exhibited a flexural strength of ¥3.5 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ¤0.33. The permeability resistance to chloride ions satisfied 2000 C after 7 days of curing for all ratios. The ratio of latex polymer to rapid-set binder material that satisfied all conditions for emergency pavement repair was ¤0.29.

  6. Deflection Control in Rigid Pavements

    NASA Astrophysics Data System (ADS)

    Varunkrishna, Nulu; Jayasankar, R.

    2017-07-01

    The need for modern transportation systems together with the high demand for perpetual pavements under the drastically increasing applied loads has led to a great deal of research on concrete as a pavement material worldwide. This research indeed instigated many modifications in concrete aiming for improving the concrete properties. Pavement Quality Concrete requires higher flexural strength and fewer deflections in hardened state. Fiber reinforcement and latex modification are two reliable approaches serving the required purposes. The concrete made with these two modifications is called Polymer-modified Fiber-reinforced concrete. The present study deals with the usage of polypropylene as fiber and SBR (Styrene Butadiene Rubber) Latex as polymer. M30 grade concrete was modified by replacing cement with two different percentages of fiber (0.5%, 1.0% of weight of cement) and with three different percentages of SBR latex (10%, 15% & 20% of weight of cement).

  7. Pervious Pavement System Evaluation- Abstract

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  8. Pervious Pavement System Evaluation- Abstract

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  9. Strain distribution in thin concrete pavement panels under three-point loading to failure with pre-pulse-pump Brillouin optical time domain analysis (Presentation Video)

    NASA Astrophysics Data System (ADS)

    Bao, Yi; Cain, John; Chen, Yizheng; Huang, Ying; Chen, Genda; Palek, Leonard

    2015-04-01

    three types of fibers were functional until the concrete panels have experienced inelastic deformation, making the distributed strain sensing technology promising for real applications in pavement engineering.

  10. Improving the distribution and reducing the magnitude of pavement damage

    NASA Astrophysics Data System (ADS)

    Barker, W. R.; Chou, U. T.

    1980-08-01

    In the analysis of flexible pavement, the layered elastic theory was used to compute the pavement response. For the rigid pavement, finite difference, layered elastic theory, and Westergard procedures were used to compute tensile stresses in concrete that formed the basis for predicting allowable stress repetitions. For flexible pavement, the only effective means to reduce pavement damage was to modify the wheel assembly to reduce stress or strain at the critical locations in the pavement systems. The most effective modification would be to increase the spacing between duals. For rigid pavements, the edge effect was critical, thus suggesting that modifications to shift the loading away from the pavement edge would be effective.

  11. Permeable Pavement Research - Edison, New Jersey

    EPA Science Inventory

    This presentation provides the background and summary of results collected at the permeable pavement parking lot monitored at the EPA facility in Edison, NJ. This parking lot is surfaced with permeable interlocking concrete pavers (PICP), pervious concrete, and porous asphalt. ...

  12. Permeable Pavement Research - Edison, New Jersey

    EPA Science Inventory

    This presentation provides the background and summary of results collected at the permeable pavement parking lot monitored at the EPA facility in Edison, NJ. This parking lot is surfaced with permeable interlocking concrete pavers (PICP), pervious concrete, and porous asphalt. ...

  13. Permeable pavement study (Edison)

    EPA Pesticide Factsheets

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha parking lot in Edison, New Jersey, that incorporated permeable interlocking concrete pavement (PICP), pervious concrete (PC), and porous asphalt (PA). Each permeable pavement type has four, 54.9-m2, lined sections that direct all infiltrate into 5.7-m3 tanks enabling complete volume collection and sampling. This paper highlights the results from a 12-month period when samples were collected from 13 rainfall/runoff events and analyzed for nitrogen species, orthophosphate, and organic carbon. Differences in infiltrate concentrations among the three permeable pavement types were assessed and compared with concentrations in rainwater samples and impervious asphalt runoff samples, which were collected as controls. Contrary to expectations based on the literature, the PA infiltrate had significantly larger total nitrogen (TN) concentrations than runoff and infiltrate from the other two permeable pavement types, indicating that nitrogen leached from materials in the PA strata. There was no significant difference in TN concentration between runoff and infiltrate from either PICP or PC, but TN in runoff was significantly larger than in the rainwater, suggesting meaningful inter-event dry de

  14. Pavement management

    SciTech Connect

    Ross, F.R.; Connor, B.; Lytton, R.L.; Darter, M.I.; Shahin, M.Y.

    1982-01-01

    The 11 papers in this report deal with the following areas: effect of pavement roughness on vehicle fuel consumption; rational seasonal load restrictions and overload permits; state-level pavement monitoring program; data requirements for long-term monitoring of pavements as a basis for development of multiple regression relations; simplified pavement management at the network level; combined priority programming of maintenance and rehabilitation for pavement networks; Arizona pavement management system: Phase 2-verification of performance prediction models and development of data base; overview of paver pavement management system; economic analysis of field implementation of paver pavement management system; development of a statewide pavement maintenance management system; and, prediction of pavement maintenance expenditure by using a statistical cost function.

  15. Pervious Pavement System Evaluation

    EPA Science Inventory

    Pervious pavement is a low impact development stormwater control. The Urban Watershed Management Branch of the U.S. Environmental Protection Agency in Edison, NJ, is evaluating concrete pavers as a popular implementation. The pollutant removal of a bench-scale permeable interlo...

  16. Strength and deformation characteristics of pavements

    NASA Astrophysics Data System (ADS)

    Shook, J. F.; Kallas, B. F.; McCullough, B. F.; Taute, A.; Rada, G.; Witczak, M. W.; Heisey, J. S.; Stokoe, K. H.; Meyer, A. H.; Huffman, M. S.

    The Colorado experimental base project was a full-scale field experment constructed with various thicknesses of two full depth hot mix sand asphalt beans, one full depth asphalt concrete base, and one thickness of a standard design with untreated base and subbase layers. Relative thicknesses of one asphalt concrete base, two hot mix sand asphalt bases, and one standard design with untreated base and subbase required to give an equal level of pavement performance were determined. Certain measured properties of the pavement and the pavement components were related to observed levels of performance by using both empirical and theoretical models for pavement behavior.

  17. Permanent Deformation of Flexible Pavements

    DTIC Science & Technology

    1977-03-01

    bitumen macadam 4.2.2 Keuper marl 4.2.3 Lean concrete 4.3 Instrumentation Layout (i) 24 25 25 26 27 27 ■’Wr-frvi-’"’-^^**tniMa "iiii ..ir...Stress Invariants 6.4 Linear or Non-linear Analysis CHAPTER SEVEN: MATERIALS CHARACTERISATION TESTS 7.1 Introduction 7.2 Dense Bitumen Macadam (ii...pavements have been tested in a newly developed pavement test facility. These pavements consisted of dense bitumen macadam placed directly over a silty

  18. Pervious Pavement System Evaluation-Paper

    EPA Science Inventory

    The use of a pervious pavement can be effective as a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete paver systems as a type of porous pavement. Although the pavers are impermeable, the spaces between the pave...

  19. Pervious Pavement System Evaluation- Abstract 1

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  20. Pervious Pavement System Evaluation- Abstract 1

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  1. Long-term Metal Performance of Three Permeable Pavements

    EPA Science Inventory

    EPA constructed a 4,000-m2 parking lot surfaced with three permeable pavements (permeable interlocking concrete pavers, pervious concrete, and porous asphalt) on the Edison Environmental Center in Edison, NJ in 2009. Samples from each permeable pavement infiltrate were collected...

  2. Update to Permeable Pavement Research at the Edison Environmental Center - proceedings

    EPA Science Inventory

    The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavements including interlocking concrete permeable pavers, p...

  3. Update to Permeable Pavement Research at the Edison Environmental Center - abstract

    EPA Science Inventory

    Abstract The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable pavers...

  4. Update to permeable pavement research at the Edison Environmental Center - slides

    EPA Science Inventory

    Abstract: The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable paver...

  5. Update to Permeable Pavement Research at the Edison Environmental Center - abstract

    EPA Science Inventory

    Abstract The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable pavers...

  6. Update to permeable pavement research at the Edison Environmental Center - slides

    EPA Science Inventory

    Abstract: The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable paver...

  7. Update to Permeable Pavement Research at the Edison Environmental Center - proceedings

    EPA Science Inventory

    The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavements including interlocking concrete permeable pavers, p...

  8. Pavement noise measurements in Poland

    NASA Astrophysics Data System (ADS)

    Zofka, Ewa; Zofka, Adam; Mechowski, Tomasz

    2017-09-01

    The objective of this study is to investigate the feasibility of the On-Board Sound Intensity (OBSI) system to measure tire-pavement noise in Poland. In general, sources of noise emitted by the modern vehicles are the propulsion noise, aerodynamic resistance and noise generated at the tire-pavement interface. In order to capture tire-pavement noise, the OBSI system uses a noise intensity probe installed in the close proximity of that interface. In this study, OBSI measurements were performed at different types of pavement surfaces such as stone mastic asphalt (SMA), regular asphalt concrete (HMA) as well as Portland cement concrete (PCC). The influence of several necessary OBSI measurement conditions were recognized as: testing speed, air temperature, tire pressure and tire type. The results of this study demonstrate that the OBSI system is a viable and robust tool that can be used for the quality evaluation of newly built asphalt pavements in Poland. It can be also applied to generate reliable input parameters for the noise propagation models that are used to assess the environmental impact of new and existing highway corridors.

  9. Thermal stability analysis under embankment with asphalt pavement and cement pavement in permafrost regions.

    PubMed

    Junwei, Zhang; Jinping, Li; Xiaojuan, Quan

    2013-01-01

    The permafrost degradation is the fundamental cause generating embankment diseases and pavement diseases in permafrost region while the permafrost degradation is related with temperature. Based on the field monitoring results of ground temperature along G214 Highway in high temperature permafrost regions, both the ground temperatures in superficial layer and the annual average temperatures under the embankment were discussed, respectively, for concrete pavements and asphalt pavements. The maximum depth of temperature field under the embankment for concrete pavements and asphalt pavements was also studied by using the finite element method. The results of numerical analysis indicate that there were remarkable seasonal differences of the ground temperatures in superficial layer between asphalt pavement and concrete pavement. The maximum influencing depth of temperature field under the permafrost embankment for every pavement was under the depth of 8 m. The thawed cores under both embankments have close relation with the maximum thawed depth, the embankment height, and the service time. The effective measurements will be proposed to keep the thermal stabilities of highway embankment by the results.

  10. Thermal Stability Analysis under Embankment with Asphalt Pavement and Cement Pavement in Permafrost Regions

    PubMed Central

    Jinping, Li; Xiaojuan, Quan

    2013-01-01

    The permafrost degradation is the fundamental cause generating embankment diseases and pavement diseases in permafrost region while the permafrost degradation is related with temperature. Based on the field monitoring results of ground temperature along G214 Highway in high temperature permafrost regions, both the ground temperatures in superficial layer and the annual average temperatures under the embankment were discussed, respectively, for concrete pavements and asphalt pavements. The maximum depth of temperature field under the embankment for concrete pavements and asphalt pavements was also studied by using the finite element method. The results of numerical analysis indicate that there were remarkable seasonal differences of the ground temperatures in superficial layer between asphalt pavement and concrete pavement. The maximum influencing depth of temperature field under the permafrost embankment for every pavement was under the depth of 8 m. The thawed cores under both embankments have close relation with the maximum thawed depth, the embankment height, and the service time. The effective measurements will be proposed to keep the thermal stabilities of highway embankment by the results. PMID:24027444

  11. Permeable pavement research – Edison, New Jersey

    EPA Science Inventory

    These are the slides for the New York City Concrete Promotional Council Pervious Concrete Seminar presentation. The basis for the project, the monitoring design and some preliminary monitoring data from the permeable pavement parking lot at the Edison Environmental Center are pre...

  12. Permeable pavement research – Edison, New Jersey

    EPA Science Inventory

    These are the slides for the New York City Concrete Promotional Council Pervious Concrete Seminar presentation. The basis for the project, the monitoring design and some preliminary monitoring data from the permeable pavement parking lot at the Edison Environmental Center are pre...

  13. Generation mechanisms of tire-pavement noise

    NASA Astrophysics Data System (ADS)

    Dare, Tyler P.

    Tire-pavement noise is the dominant source of traffic noise at highway speeds. It is the result of a combination of several noise generation mechanisms, including tire carcass vibration and tread block vibration. Because multiple mechanisms are involved, it is difficult to predict the effects of changes in pavement parameters on tire-pavement noise. In this research, a set of experimental techniques were developed to decompose a measured tire-pavement noise spectrum into a set of constituent spectra relating to each generation mechanism. Three principal mechanisms were identified: treadband vibration, sidewall vibration, and tangential tread block vibration. By combining the constituent spectra associated with these mechanisms, it was possible to accurately predict the total tire-pavement noise spectrum. The constituent spectra were fit to tire-pavement noise data measured on asphalt and concrete pavements at highway speeds. It was found that the constituent spectra fit the measured data well, and a two-parameter model was developed to predict tire-pavement noise levels from pavement texture data.

  14. Polymer concrete patching manual

    NASA Astrophysics Data System (ADS)

    Fontana, J. J.; Bartholomew, J.

    1982-06-01

    The practicality of using polymer concrete to repair deteriorated portland cement concrete bridge decks and pavements was demonstrated. This manual outlines the procedures for using polymer concrete as a rapid patching material to repair deteriorated concrete. The process technology, materials, equipment, and safety provisions used in manufacturing and placing polymer concrete are discussed. Potential users are informed of the various steps necessary to insure successful field applications of the material.

  15. Microorganism Removal in Permeable Pavement Parking Lots ...

    EPA Pesticide Factsheets

    Three types of permeable pavements (pervious concrete, permeable interlocking concrete pavers, and porous asphalt) were monitored at the Edison Environmental Center in Edison, New Jersey for indicator organisms such as fecal coliform, enterococci, and E. coli. Results showed that porous asphalt had much lower concentration in monitored infiltrate compared to pervious concrete and permeable interlocking concrete pavers. Concentrations of monitored organisms in infiltrate from porous asphalt were consistently below the bathing water quality standard. Fecal coliform and enterococci exceeded bathing water quality standards more than 72% and 34% of the time for permeable interlocking concrete pavers and pervious concrete, respectively. Purpose is to evaluate the performance of permeable pavement in removing indicator organisms from infiltrating stormwater runoff.

  16. Quantifying Evaporation in a Permeable Pavement System ...

    EPA Pesticide Factsheets

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. The U.S. Environmental Protection Agency (USEPA) constructed a 0.4-ha parking lot in Edison, NJ, that incorporated three different permeable pavement types in the parking lanes – permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). An impermeable liner installed 0.4 m below the driving surface in four 11.6-m by 4.74-m sections per each pavement type captures all infiltrating water and routes it to collection tanks that can contain events up to 38 mm. Each section has a design impervious area to permeable pavement area ratio of 0.66:1. Pressure transducers installed in the underdrain collection tanks measured water level for 24 months. Level was converted to volume using depth-to-volume ratios for individual collection tanks. Using a water balance approach, the measured infiltrate volume was compared to rainfall volume on an event-basis to determine the rainfall retained in the pavement strata and underlying aggregate. Evaporation since the previous event created additional storage in the pavement and aggregate layers. Events were divided into three groups based on antecedent dry period (ADP) and three, four-month categories of potential e

  17. Refining the maintenance techniques for Interlocking Concrete Paver GIs

    EPA Science Inventory

    Surface clogging adversely affects the performance of Interlocking Concrete Pavements (ICP) by reducing their ability to infiltrate stormwater runoff. The clogging rate is a function of pavement type, traffic loading, surrounding physical environment and maintenance treatments. ...

  18. Refining the maintenance techniques for Interlocking Concrete Paver GIs

    EPA Science Inventory

    Surface clogging adversely affects the performance of Interlocking Concrete Pavements (ICP) by reducing their ability to infiltrate stormwater runoff. The clogging rate is a function of pavement type, traffic loading, surrounding physical environment and maintenance treatments. ...

  19. Energy equivalents for selected pavement materials: Their production and placement

    NASA Astrophysics Data System (ADS)

    Lane, K. R.

    1981-03-01

    Energy requirements for selected pavement surfaces are discussed. Energy requirements for hot-mixed bituminous recycling and portland cement concrete recycling projects are presented along with conventional pavement methods. Energy requirements for conventional thin surface treatments are also discussed. Environmental analyses involving both air and noise quality measurement are included for various recycling and conventional paving options.

  20. 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.)

  1. Microorganism Removal in Permeable Pavement Parking Lots in Edison Environmental Center, New Jersey

    EPA Science Inventory

    Three types of permeable pavements (pervious concrete, permeable interlocking concrete pavers, and porous asphalt) were monitored at the Edison Environmental Center in Edison, New Jersey for indicator organisms such as fecal coliform, enterococci, and E. coli. Results showed tha...

  2. Performance Evaluation of Pre-Cast Slabs for Contingency Rigid Airfield Pavement Damage Repair

    DTIC Science & Technology

    2010-10-01

    AFRL-RX-TY-TP-2010-0079 PERFORMANCE EVALUATION OF PRE-CAST SLABS FOR CONTINGENCY RIGID AIRFIELD PAVEMENT DAMAGE REPAIR Reza Ashtiani...pre-cast concrete, concrete panels, airfield pavement damage, airfield repair, airfield rigid pavements U U U UU 37 Thomas, Troy Reset 1 Repair...NUMBER (Include area code) 13-OCT-2010 Presentation (PREPRINT) 01-JAN-2010 -- 01-OCT-2010 Performance Evaluation of Pre-Cast Slabs for Contingency Rigid

  3. Pavement nondestructive evaluation using finite-element dynamic simulation

    NASA Astrophysics Data System (ADS)

    Uddin, W.; Hackett, R. M.

    1996-11-01

    This paper describes the nondestructive evaluation devices, visual distress survey and coring used to investigate jointed concrete pavement performance in northern Mississippi. 3D finite-element models were developed to simulate in-service conditions and to characterize in-situ material properties. Reasonable good agreement is found between in-situ moduli backcalculated from the dynamic analysis of falling weight deflectometer (FWD) deflections measured on selected pavements and laboratory moduli. Effects of load pulse shape, cracking, and discontinuities on the surface deflection response of pavements subjected to FWD load wee also investigated. It is shown that 3D analysis of temperature distribution and resulting thermal stresses play a significant role int he performance of concrete pavements. The study results demonstrated the extensive usefulness of the finite-element dynamic analysis and limitations of the static multilayered analysis and other pavement analysis programs which do not allow for crack modeling and dynamic analysis.

  4. Variability of pavement noise benefit by vehicle type

    NASA Astrophysics Data System (ADS)

    Rochat, Judith L.; Read, David R.

    2005-09-01

    The Volpe Center Acoustics Facility, in support of the California Department of Transportation (Caltrans), is participating in a long-term study to assess several types of pavement for the purpose of noise abatement. On a four-mile stretch of a two-lane highway in Southern California, several asphalt pavement overlays are being examined. Acoustical, meteorological, and traffic data are collected in each pavement overlay section, where microphones are deployed at multiple distances and heights. Single vehicle pass-by events are recorded primarily for three vehicle types: automobiles, medium trucks, and heavy trucks. Data are analyzed to determine the noise benefit of each pavement as compared to the reference dense-graded asphaltic concrete (DGAC); this includes a modified Statistical Pass-By Index as well as average Lmax values for each vehicle type. In addition, 1/3-octave band data are examined. Automobiles and heavy trucks are the focus of this paper, where benefits due to pavement will be presented for three pavement types: open-graded asphaltic concrete (OGAC) of 75 mm thickness, open-graded asphaltic concrete (OGAC) of 30 mm thickness, and rubberized asphaltic concrete, Type O (open) (RAC) of 30 mm thickness. Average Lmax values and spectral data show that noise benefits due to pavement can vary by vehicle type.

  5. Thermal cracking of rubber modified pavements, May 1995. Final report

    SciTech Connect

    Raad, L.; Yuan, X.; Saboundjian, S.

    1995-05-01

    In accordance with the original ISTEA mandate (1991) to use crumb tire rubber in pavements, Alaska would be required to use about 250 tons of used tire rubber starting in 1994 and increasing to about 1,000 tons of rubber in 1997 and each year thereafter. A number of pavements using crumb rubber modifiers have been built in the state and have been in service for periods of 8 to 15 years. Knowledge of the behavior of these rubber-modified pavements under extreme climate conditions, particularly in relation to their low temperature cracking resistance, is necessary for future design and construction of rubberized pavements in Alaska. This report presents results of a study to determine the low temperature cracking resistance of rubber modified pavements in Alaska in comparison with conventional asphalt concrete pavements.

  6. Expedient Repair Materials for Roadway Pavements

    DTIC Science & Technology

    2005-03-01

    cores used for the adhesion test was thin-cut with a concrete saw to expose an aggregate face on which the oven-aged mixture was compacted (Figure 4...asphalt cement with various antistrip and high- adhesion additives. An open-graded, high-quality, locally available aggregate is required for blending...www.qprcoldpatch.com 3. Description: QPR is a cold-mix patch material for asphalt and concrete pavements. The binder is a proprietary modified bitumen . The aggregate

  7. 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.

  8. Recycled materials in asphalt pavements, January 1980-June 1991 (citations from the NTIS database). Rept. for Jan 80-Jun 91

    SciTech Connect

    Not Available

    1991-06-01

    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. (The bibliography contains 75 citations.) (Also includes title list and subject index.)

  9. Reducing traffic noise with quieter pavements

    NASA Astrophysics Data System (ADS)

    Donavan, Paul

    2005-09-01

    In recent years, interest has increased in the use of pavement type to reduce traffic noise. This has been driven by public concern over noise from freeways and state transportation agencies' interest in using pavement instead of sound walls to mitigate traffic noise. Beginnings of the recent interest go back to 1998 with the formation of the Institute for Safe, Quiet & Durable Highways at Purdue University and the initiation long-term research by the California Department of Transportation (Caltrans) on the effectiveness of quieter pavements. In 2002, the State of Arizona announced plans to overlay 115 miles of concrete freeway in the greater Phoenix area with a quieter asphalt rubber surface. This turned into the first Quiet Pavement Pilot Program in partnership between Federal Highway Administration (FHWA) and the Arizona Department of Transportation. Since that time, the FHWA in cooperation with the American Association of State Highway Transportation Agencies conducted a fact finding ``Scan'' tour in Europe to evaluate their quiet pavement technology and policy. This was followed by the first comparative tire/pavement noise testing in the US and Europe using the same procedures and test tires. The results, issues, and future directions surrounding these activities will be discussed.

  10. Nitrogen Transformations in Three Types of Permeable Pavement

    EPA Science Inventory

    In 2009, USEPA constructed a 0.4-ha (1-ac) parking lot at the Edison Environmental Center in Edison, NJ, that incorporated three different permeable pavement types - permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). The driving lanes...

  11. Nitrogen Transformations in Three Types of Permeable Pavement

    EPA Science Inventory

    In 2009, USEPA constructed a 0.4-ha (1-ac) parking lot at the Edison Environmental Center in Edison, NJ, that incorporated three different permeable pavement types - permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). The driving lanes...

  12. Long-term Metal Performance of Three Permeable Pavements ...

    EPA Pesticide Factsheets

    EPA constructed a 4,000-m2 parking lot surfaced with three permeable pavements (permeable interlocking concrete pavers, pervious concrete, and porous asphalt) on the Edison Environmental Center in Edison, NJ in 2009. Samples from each permeable pavement infiltrate were collected for six years beginning in January 2010 and analyzed for twenty-two metals. Although the infiltrate metals concentrations varied by surface, metal concentrations in more than 99% of the permeable pavement infiltrate samples met both the groundwater effluent limitations and maximum contaminant levels in national primary drinking water regulations for barium, chromium, copper, manganese, nickel and zinc. Arsenic, cadmium, lead and antimony met those standards in 60% to 98% of the samples with no measurable difference found among pavements. Aluminum and iron in pervious concrete and porous asphalt infiltrates met standards at more than 90%, however permeable interlocking concrete paver infiltrates have 50% and 93% samples exceeds standards, respectively. Concentrations of arsenic, iron, potassium, lithium, magnesium, antimony, tin, manganese, and zinc in all permeable pavement infiltrates decreased with time, whereas, aluminum, barium, calcium, chromium and strontium in porous asphalt infiltrates increased. Most metal concentrations in permeable pavement infiltrates either exhibited no significant difference between snow/no-snow seasons or showed statistically larger concentrations

  13. Hybrid green permeable pave with hexagonal modular pavement systems

    NASA Astrophysics Data System (ADS)

    Rashid, M. A.; Abustan, I.; Hamzah, M. O.

    2013-06-01

    Modular permeable pavements are alternatives to the traditional impervious asphalt and concrete pavements. Pervious pore spaces in the surface allow for water to infiltrate into the pavement during rainfall events. As of their ability to allow water to quickly infiltrate through the surface, modular permeable pavements allow for reductions in runoff quantity and peak runoff rates. Even in areas where the underlying soil is not ideal for modular permeable pavements, the installation of under drains has still been shown to reflect these reductions. Modular permeable pavements have been regarded as an effective tool in helping with stormwater control. It also affects the water quality of stormwater runoff. Places using modular permeable pavement has been shown to cause a significant decrease in several heavy metal concentrations as well as suspended solids. Removal rates are dependent upon the material used for the pavers and sub-base material, as well as the surface void space. Most heavy metals are captured in the top layers of the void space fill media. Permeable pavements are now considered an effective BMP for reducing stormwater runoff volume and peak flow. This study examines the extent to which such combined pavement systems are capable of handling load from the vehicles. Experimental investigation were undertaken to quantify the compressive characteristics of the modular. Results shows impressive results of achieving high safety factor for daily life vehicles.

  14. Permanent Deformation of Flexible Pavements.

    DTIC Science & Technology

    1980-06-01

    speeds actually used during testing are detailed in Chapters 3 and 4. Load range = 0-15 kN Tyre pressure = 530 kPa Contact area at 10 kN = 0.02 m 2...The difference between tyre pressure and contact stress is probably due to the stiffness of the side walls of the tyre . 2.2 PAVEMENT INSTRUMENTATION...of wet bricks in a waterproofed concrete lined pit 4.9 m long, 2.4 m wide and 1.5 m deep. A triple legged pneumatic tamper was used to compact each

  15. Research of cost aspects of cement pavements construction

    NASA Astrophysics Data System (ADS)

    Bezuglyi, Artem; Illiash, Sergii; Tymoshchuk, Oleksandr

    2017-09-01

    The tendency to increasing traffic volume on public roads and to increased axle loads of vehicles makes the road scientists to develop scientifically justified methods for preserving the existing and developing the new transport network of Ukraine. One of the options for solving such issues is the construction of roads with rigid (cement concrete) pavement. However, any solution must be justified considering technical and economic components. This paper presents the results of the research of cost aspects of cement pavements construction.

  16. Use of scrap rubber in asphalt pavement surfaces. Special report

    SciTech Connect

    Eaton, R.A.; Roberts, R.J.; Blackburn, R.R.

    1991-12-01

    Scrap tire rubber was mixed into an asphalt concrete wearing course to study the effect of ice disbonding from the pavement surface under traffic. Rubber contents of 0, 3, 6, and 12% by weight were studied. Initial laboratory ice disbonding test results led to the development of a new paving material, Chunk Rubber Asphalt Concrete (CRAC), that uses larger pieces of rubber in a much denser asphalt concrete mix. Strength values doubled and ice disbonding performance was enhanced.

  17. Morphological Algorithms For The Analysis Of Pavement Structure

    NASA Astrophysics Data System (ADS)

    Grivas, Dimitri A.; Skolnick, Michael M.

    1989-11-01

    The applicability of morphological image processing techniques for the description of condition and analysis of pavement surfaces is examined. Morphological techniques can be used in the measurement of pavement media consisting of grain (aggregates) and binding substances (bituminous or Portland cement mixtures). Measurements of size and size distributions on surface features related to texture and distresses can be obtained via morphological opening and closing transformations and distributions. When correlated with actual physical measurements of such quantities, the presented morphological measures of size and size distributions may prove to be useful in characterizing the surface condition of both asphalt and concrete pavement structures.

  18. PREPACKED CONCRETE.

    DTIC Science & Technology

    Twenty four hardened plain concrete wallettes , each 31 in. high by 25 in. wide by 6 in. thick, were sawed into various rectangular parallelepipeds...The wallettes represented three groups of prepacked concrete: reference aggregate intruded with fresh-water grout, coral aggregate with fresh-water...prismatic test specimens were involved in the program for determining the effectsof: type of mixing water, type of wiremesh cover atop the wallette form

  19. Development of Laboratory Testing Criteria for Evaluating Cementitious, Rapid-Setting Pavement Repair Materials

    DTIC Science & Technology

    2011-04-01

    ER D C/ G SL T R- 11 -1 3 Development of Laboratory Testing Criteria for Evaluating Cementitious, Rapid-Setting Pavement Repair...unlimited. ERDC/GSL TR-11-13 April 2011 Development of Laboratory Testing Criteria for Evaluating Cementitious, Rapid-Setting Pavement Repair...surface repairs in portland cement concrete (PCC) pavements that provide short set times, high early strengths, and durability to withstand heavy loads

  20. Overview of the Arizona Quiet Pavement Program

    NASA Astrophysics Data System (ADS)

    Donavan, Paul; Scofield, Larry

    2005-09-01

    The Arizona Quiet Pavement Pilot Program (QP3) was initially implemented to reduce highway related traffic noise by overlaying most of the Phoenix metropolitan area Portland cement concrete pavement with a one inch thick asphalt rubber friction coarse. With FHWA support, this program represents the first time that pavement surface type has been allowed as a noise mitigation strategy on federally funded projects. As a condition of using pavement type as a noise mitigation strategy, ADOT developed a ten-year, $3.8 million research program to evaluate the noise reduction performance over time. Historically, pavement surface type was not considered a permanent solution. As a result, the research program was designed to specifically address this issue. Noise performance is being evaluated through three means: (1) conventional roadside testing within the roadway corridor (e.g., far field measurements within the right-of-way) (2) the use of near field measurements, both close proximity (CPX) and sound intensity (SI); and (3) far field measurements obtained beyond the noise barriers within the surrounding neighborhoods. This paper provides an overview of the program development, presents the research conducted to support the decision to overlay the urban freeway, and the status of current research.

  1. Experimental pavement using household waste slag

    SciTech Connect

    Kouda, Masahiro

    1996-12-31

    Municipal wastes used to be simply landfilled, but because of increasing difficulty in finding disposal sites, it became common practice to incinerate wastes and landfill the ash. In view of rapidly dwindling landfill sites, the author thought that the landfill site problem might be solved by finding a way to utilize slag made from incinerator ash. In this paper, a method for utilizing water-granulated slag as an asphalt pavement material is discussed. On the basis of laboratory test results, trial paving using base course materials consisting of crushed stone and 25 or 50% slag was carried out, paying attention primarily to bearing capacity. Marshall tests and fatigue resistance tests were conducted to determine the optimum content of water-granulated slag, and it was concluded that quality comparable to that of conventional asphalt concrete was attained at the slag content of 25% or less and that no problem would arise if the slag content was kept at 60% or less of the fine aggregate content. The mix proportions thus determined were also tested through experimental paving. A follow-up study to evaluate the durability of the experimental pavements confirmed that the experimental pavements were comparable in performance with conventional asphalt concrete pavements. This paper also reports on some problems encountered that need to be solved before utilizing water-granulated slag.

  2. Seismic Behavior and Retrofit of Concrete Columns of Old R.C. Buildings Reinforced With Plain Bars

    SciTech Connect

    Marefat, M. S.; Arani, K. Karbasi; Shirazi, S. M. Hassanzadeh; Amrollahi, A.

    2008-07-08

    Seismic rehabilitation of old buildings has been a major challenge in recent years. The first step in seismic rehabilitation is evaluation of the existing capacity and the seismic behaviour. For investigation of the seismic behaviour of RC members of a real old building in Iran which has been designed and constructed by European engineers in 1940, three half-scale column specimens reinforced with plain bars have been tested. The tests indicate significant differences between the responses of specimens reinforced by plain bars relative to those reinforced by deformed bars. A regular pattern of cracking and a relatively brittle behaviour was observed while a relatively large residual strength appeared after sudden drop of initial strength and stiffness due to slip of longitudinal bars.

  3. 9 CFR 91.26 - Concrete flooring.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Concrete flooring. 91.26 Section 91.26... LIVESTOCK FOR EXPORTATION Inspection of Vessels and Accommodations § 91.26 Concrete flooring. (a) Pens aboard an ocean vessel shall have a 3 inch concrete pavement, proportioned and mixed to give 2000...

  4. 9 CFR 91.26 - Concrete flooring.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Concrete flooring. 91.26 Section 91.26... LIVESTOCK FOR EXPORTATION Inspection of Vessels and Accommodations § 91.26 Concrete flooring. (a) Pens aboard an ocean vessel shall have a 3 inch concrete pavement, proportioned and mixed to give 2000...

  5. 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.)

  6. 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…

  7. 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…

  8. Pavement condition data analysis

    SciTech Connect

    Zaniewski, J.P.; Hudson, S.W.; Hudson, W.R.

    1987-07-01

    This paper describes a computer methodology for analyzing pavement condition data to define inputs for pavement management systems. This system of programs was developed during a Federal Highway Administration research project. In the project, eight state highway departments were studied to determine the types of pavement condition data collected, procedures used for collecting data, the inputs to the states' pavement management systems, and computer programs used by the states to analyze raw pavement condition data. Several of the programs were assembled into the Method for Analyzing Pavement Condition, MAPCON, during a project performed at Pennsylvania State University. These and other existing or new programs (a total of 18) were identified, tested, modified, and incorporated onto a MS/DOS microcomputer system. MAPCON guides the user through selection of analysis method, raw data entry, and data analysis.

  9. Recycled materials in asphalt pavements. October 1973-November 1989 (Citations from the NTIS data base). Report for October 1973-November 1989

    SciTech Connect

    Not Available

    1989-12-01

    This 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 110 citations fully indexed and including a title list.)

  10. Pavement recycling catching on

    SciTech Connect

    Dallaire, G.

    1980-11-01

    The soaring costs of asphalt, aggregates, energy, and labor have revived interest in the recycling of old pavements and road bases. Two types of techniqueshot mix recycling and cold mix recycling are described and compared. The experiences of Wisconsin and Texas with pavement recycling are reviewed. Wisconsin uses the hot mix recycling, while Texas refurbishes its roads with the cold mix recycling. One contractor's doubts about surface recycling of pavements are outlined. (13 photos)

  11. Life cycle assessment of representative swiss road pavements for national roads with an accompanying life cycle cost analysis.

    PubMed

    Gschösser, Florian; Wallbaum, Holger

    2013-08-06

    The subject of this paper is an environmental life cycle assessment (LCA) and life cycle cost analysis (LCCA) of processes needed to construct and maintain representative Swiss asphalt, concrete, and composite pavements (including subbase layers) applicable for the Swiss national road network over a period of 75 years. The environmental indicators analyzed are the global warming potential indicator, the nonrenewable cumulative energy demand, and the Swiss ecological scarcity indicator. Processes of the use phase of the road (fuel consumption, noise, etc.) have been evaluated qualitatively based on intensive research. The study shows that the global warming potential of concrete and asphalt pavements equilibrates over the analysis period and that concrete pavements compared to asphalt and composite pavements offer advantages in regards to the nonrenewable cumulative energy demand, the ecological scarcity indicator, and life cycle costs. The qualitative evaluation of the processes of the use phase shows for example the positive qualities of concrete pavements regarding fuel consumption and permanent noise properties.

  12. Paint Pavement Marking Performance Prediction Model That Includes the Impacts of Snow Removal Operations

    DTIC Science & Technology

    2011-03-01

    Hypothesized that snow plows wear down mountain road pavement markings. 2007 Craig et al. -Edge lines degrade slower than center/skip lines 2007...retroreflectivity to create the models. They discovered that paint pavement markings last 80% longer on Portland Cement Concrete than Asphalt Concrete at low AADT...retroreflectivity, while yellow markings lost 21%. Lu and Barter attributed the sizable degradation to snow removal, sand application, and studded

  13. Latex improvement of recycled asphalt pavement

    NASA Astrophysics Data System (ADS)

    Drennon, C.

    1982-08-01

    The performance of a single unmodified milled recycled asphalt concrete was compared to milled asphalt concrete modified by addition of three types of rubber latex. Latex was added at 2, 3, 5, and 8 percent latex by weight of asphalt in the asphalt concrete. Lattices used were a styrene butadiene (SBR), a natural rubber (NR), an acrylonitrile butadiene (NBR), and four varieties of out of specification SBR lattices. Marshall tests, while indecisive, showed a modest improvement in properties of SBR and NR added material at 3 and 5 percent latex. Addition of NBR latex caused deterioration in Marshall stability and flow over that of control. Repeated load tests were run using the indirect tensile test, analyzed by the VESYS program, which computes life of pavements. Repeated load tests showed improvement in asphalt concrete life when 3 and 5 percent SBR was added. Improvement was also shown by the out of specification SBR.

  14. 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…

  15. 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.

  16. Pavement management practices. Final report

    SciTech Connect

    Peterson, D.E.

    1987-11-01

    This synthesis will be of interest to pavement designers, maintenance engineers, and others responsible for the management of highway pavements. Information is presented on pavement management systems - the established, documented procedures used to treat all activities involved in providing and sustaining pavements in an acceptable condition. As highway agencies focus more attention on maintenance and rehabilitation of highway networks, the use of some form of a pavement management system becomes increasingly important. This report of the Transportation Research Board describes the features, applicability, and used of a pavement management system and recommends five general steps for implementing a new pavement management system or improving an existing system.

  17. Update to permeable pavement research at the Edison ...

    EPA Pesticide Factsheets

    Abstract: The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable pavers; porous concrete; and permeable asphalt. The parking lot is instrumented with water content reflectometers and thermistors for continuous monitoring and has four lined sections for each surface to capture permeable pavement infiltrate for water quality analyses.Previous technical releases concerning the demonstration site focused on monitoring techniques, observed chloride and nutrient concentrations, and infiltration and evaporation rates. Thispresentation summarizes past findings and addresses current water quality efforts. This presentation summarizes past findings and addresses current water quality efforts.

  18. The effect of loading time on flexible pavement dynamic response: a finite element analysis

    NASA Astrophysics Data System (ADS)

    Yin, Hao; Solaimanian, Mansour; Kumar, Tanmay; Stoffels, Shelley

    2007-12-01

    Dynamic response of asphalt concrete (AC) pavements under moving load is a key component for accurate prediction of flexible pavement performance. The time and temperature dependency of AC materials calls for utilizing advanced material characterization and mechanistic theories, such as viscoelasticity and stress/strain analysis. In layered elastic analysis, as implemented in the new Mechanistic-Empirical Pavement Design Guide (MEPDG), the time dependency is accounted for by calculating the loading times at different AC layer depths. In this study, the time effect on pavement response was evaluated by means of the concept of “pseudo temperature.” With the pavement temperature measured from instrumented thermocouples, the time and temperature dependency of AC materials was integrated into one single factor, termed “effective temperature.” Via this effective temperature, pavement responses under a transient load were predicted through finite element analysis. In the finite element model, viscoelastic behavior of AC materials was characterized through relaxation moduli, while the layers with unbound granular material were assumed to be in an elastic mode. The analysis was conducted for two different AC mixtures in a simplified flexible pavement structure at two different seasons. Finite element analysis results reveal that the loading time has a more pronounced impact on pavement response in the summer for both asphalt types. The results indicate that for reasonable prediction of dynamic response in flexible pavements, the effect of the depth-dependent loading time on pavement temperature should be considered.

  19. State-of-the-art and prospect for self-healing asphalt concrete

    NASA Astrophysics Data System (ADS)

    Xiao, Dong

    2017-08-01

    In order to solve the problem of asphalt concrete pavement cracks, this paper summarizes the principle of self-healing asphalt concrete, and describes asphalt concrete self-healing technology in various countries. This paper also analyses the factors of influencing the self-healing ability of asphalt concrete and the evaluation index, and describes the prospect of asphalt concrete self-healing technology.

  20. Assessment of dynamic properties and stiffness of composite bridges with pavement defects

    NASA Astrophysics Data System (ADS)

    Kartopol'tsev, Vladimir; Kartopol'tsev, Andrei; Kolmakov, Boris

    2017-01-01

    This paper is aimed at assessing the dynamic properties and stiffness of the reinforced concrete roadway slab under live loads that impact composite bridge girders considering pavement defects. A special attention is paid to the reinforced concrete roadway slab as a transfer member of forced oscillations. The test results obtained for bridges with different spans ranging from 24 to 110 m are presented to assess the behavior of the reinforced concrete roadway slab and the dynamic stiffness of bridge span allowed for the pavement defects. Dynamic tests are carried out under controlled and random loads that simulate live load interaction with the span and the pavement with defects. The differential equations are presented for vertical oscillations of spans, pavement defect parameter, Eigen frequency and others. As a result of the experimental research the equation is derived to ascertain the dynamic stiffness of the vehicle-span system.

  1. Update to Permeable Pavement Research at the Edison ...

    EPA Pesticide Factsheets

    The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavements including interlocking concrete permeable pavers, pervious concrete, and porous asphalt. The permeable pavements are limited to parking spaces while adjacent driving lanes are impermeable and drain to the permeable surfaces. The parking lot is instrumented for continuous monitoring with thermistors and water content reflectometers that measure moisture as infiltrate passes through the storage gallery beneath the permeable pavements into the underlying native soil. Each permeable surface of the parking lot has four lined sections that capture infiltrate in tanks for water quality analyses; these tanks are capable of holding volumes up to 4.1 m3, which represents up to 38 mm (1.5 in.) for direct rainfall on the porous pavement and runoff from adjacent driving lanes that drain into the permeable surface.Previous technical releases concerning the demonstration site focused on monitoring techniques, observed chloride and nutrient concentrations, surface hydrology, and infiltration and evaporation rates. This presentation summarizes these past findings and addresses current water quality efforts including pH, solids analysis, total organic carbon, and chemical oxygen demand. Stormwater runoff continues to be a major cause of water pollution in

  2. Evaluation of Precast Panels for Airfield Pavement Repair. Phase 1: System Optimization and Test Section Construction

    DTIC Science & Technology

    2013-06-01

    installation for emergency and contingency portland cement concrete (PCC) pavement repairs. Seven precast concrete panels were fabricated for use in an...the investigation were used to develop fabrication and installation procedures and to determine the supplies and equipment required to construct...86  5  Fabrication of Precast Panels

  3. Stormwater quality of spring-summer-fall effluent from three partial-infiltration permeable pavement systems and conventional asphalt pavement.

    PubMed

    Drake, Jennifer; Bradford, Andrea; Van Seters, Tim

    2014-06-15

    This study examined the spring, summer and fall water quality performance of three partial-infiltration permeable pavement (PP) systems and a conventional asphalt pavement in Ontario. The study, conducted between 2010 and 2012, compared the water quality of effluent from two Interlocking Permeable Concrete Pavements (AquaPave(®) and Eco-Optiloc(®)) and a Hydromedia(®) Pervious Concrete pavement with runoff from an Asphalt control pavement. The usage of permeable pavements can mitigate the impact of urbanization on receiving surface water systems through quantity control and stormwater treatment. The PP systems provided excellent stormwater treatment for petroleum hydrocarbons, total suspended solids, metals (copper, iron, manganese and zinc) and nutrients (total-nitrogen and total-phosphorus) by reducing event mean concentrations (EMC) as well as total pollutant loadings. The PPs significantly reduced the concentration and loading of ammonia (NH4(+)+NH3), nitrite (NO2(-)) and organic-nitrogen (Org-N) but increased the concentration and loading of nitrate (NO3(-)). The PP systems had mixed performances for the treatment of phosphate (PO4(3-)). The PP systems increased the concentration of sodium (Na) and chloride (Cl) but EMCs remained well below recommended levels for drinking water quality. Relative to the observed runoff, winter road salt was released more slowly from the PP systems resulting in elevated spring and early-summer Cl and Na concentrations in effluent. PP materials were found to introduce dissolved solids into the infiltrating stormwater. The release of these pollutants was verified by additional laboratory scale testing of the individual pavement and aggregate materials at the University of Guelph. Pollutant concentrations were greatest during the first few months after construction and declined rapidly over the course of the study.

  4. A pavement Moisture Accelerated Distress (MAD) identification system, volume 2

    NASA Astrophysics Data System (ADS)

    Carpenter, S. H.; Darter, M. I.; Dempsey, B. J.

    1981-09-01

    A users manual is designed which provides the engineer with a rational method of examining a pavement and determining rehabilitation needs that are related to the causes of the existing distress, particularly moisture related distress. The key elements in this procedure are the MAD Index developed in Volume 1, the Pavement Condition Index (PCI) and the Moisture Distress Index (MDI). Step by step procedures are presented for calculating each parameter. Complete distress identification manuals are included for asphalt surfaced highways and jointed reinforced concrete highways with pictures and descriptions of all major distress types. Descriptions of the role moisture plays in the development of each distress type are included.

  5. Surface runoff from full-scale coal combustion product pavements during accelerated loading

    SciTech Connect

    Cheng, C.M.; Taerakul, P.; Tu, W.; Zand, B.; Butalia, T.; Wolfe, W.; Walker, H.

    2008-08-15

    In this study, the release of metals and metalloids from full-scale portland cement concrete pavements containing coal combustion products (CCPs) was evaluated by laboratory leaching tests and accelerated loading of full-scale pavement sections under well-controlled conditions. An equivalent of 20 years of highway traffic loading was simulated at the OSU/OU Accelerated Pavement Load Facility (APLF). Three types of portland cement concrete driving surface layers were tested, including a control section (i.e., ordinary portland cement (PC) concrete) containing no fly ash and two sections in which fly ash was substituted for a fraction of the cement; i.e., 30% fly ash (FA30) and 50% fly ash (FA50). In general, the concentrations of minor and trace elements were higher in the toxicity characteristic leaching procedure (TCLP) leachates than in the leachates obtained from synthetic precipitation leaching procedure and ASTM leaching procedures. Importantly, none of the leachate concentrations exceeded the TCLP limits or primary drinking water standards. Surface runoff monitoring results showed the highest release rates of inorganic elements from the FA50 concrete pavement, whereas there were little differences in release rates between PC and FA30 concretes. The release of elements generally decreased with increasing pavement loading. Except for Cr, elements were released as particulates (>0.45 {mu} m) rather than dissolved constituents. The incorporation of fly ash in the PC cement concrete pavements examined in this study resulted in little or no deleterious environmental impact from the leaching of inorganic elements over the lifetime of the pavement system.

  6. Refining the maintenance techniques for Interlocking Concrete Paver GIs - abstract

    EPA Science Inventory

    Surface clogging adversely affects the performance of Interlocking Concrete Pavements (ICP) by reducing their ability to infiltrate stormwater runoff. Determining the correct methods for remedial maintenances is crucial to recovering and maintaining efficient ICP performance. T...

  7. Refining the maintenance techniques for Interlocking Concrete Paver GIs - abstract

    EPA Science Inventory

    Surface clogging adversely affects the performance of Interlocking Concrete Pavements (ICP) by reducing their ability to infiltrate stormwater runoff. Determining the correct methods for remedial maintenances is crucial to recovering and maintaining efficient ICP performance. T...

  8. High altitude premium pavements

    NASA Astrophysics Data System (ADS)

    Abel, F.; Proctor, J.

    1980-02-01

    The effect on performance that various additives and, or compaction had on the performance of pavements was evaluated. The following additives were evaluated: Anti-stripping additives, ground scrap rubber and carbon black. Samples were also evaluated at approximately 0, 3, 10 and 15% voids to determine the effect compaction had on the performance of the pavement. The resilient modulus, effect of water on cohesion of compacted bituminous mixtures and an accelerated moisture damage test was performed on each design mix. Most of the additives did not show significant, if any, improvement in the laboratory test results. The best improvement in laboratory test results came from the anti-stripping asphalt additives, which is one of the least costly and simplest to include in the pavement mixture.

  9. Experimental pavement delineation treatments

    NASA Astrophysics Data System (ADS)

    Bryden, J. E.; Lorini, R. A.

    1981-06-01

    Visibility and durability of materials used to delineate shoulders and medians adjacent to asphalt pavements were evaluated. Materials evaluated were polysulfide and coal tar epoxies, one and two component polyesters, portland cement, acrylic paints, modified-alkyd traffic paint, preformed plastic tape, and thermoplastic markings. Neat applications, sand mortars, and surface treatments were installed in several geometric patterns including cross hatches, solid median treatments, and various widths of edge lines. Thermoplastic pavement markings generally performed very well, providing good visibility under adverse viewing conditions for at least 4 years. Thermoplastic 4 in. wide edge lines appear to provide adequate visibility for most conditions.

  10. Cooler reflective pavements give benefits beyond energy savings: durability and illumination

    SciTech Connect

    Pomerantz, Melvin; Akbari, Hashem; Harvey, John T.

    2000-06-01

    City streets are usually paved with asphalt concrete because this material gives good service and is relatively inexpensive to construct and maintain. We show that making asphalt pavements cooler, by increasing their reflection of sunlight, may lead to longer lifetime of the pavement, lower initial costs of the asphalt binder, and savings on street lighting and signs. Excessive glare due to the whiter surface is not likely to be a problem.

  11. Recycling of water-susceptible pavements

    NASA Astrophysics Data System (ADS)

    Maupin, G. W.

    1980-05-01

    Several bituminous concrete interstate pavements that experienced failures suspected to have been caused by stripping were investigated. On two projects, the degree of deterioration, potential serviceability, and possible remedial measures were studied. Cores were taken to determine the degreee of stripping and tensile strength, and dynaflect tests were performed. An emulsion mix design was developed for stripped bituminous concrete removed from another project with the expectation that it could be used as a surface mix on a highway with a low traffic volume. While this expectation was not realized, it was concluded that the material is suitable for use in a base mix. A maintenance resurfacing on a fourth project that experienced stripping failure is being monitored and the performance is being evaluated.

  12. Determination of importance of various parameters on performance of rigid pavement joints

    NASA Astrophysics Data System (ADS)

    Cook, J. P.; Minkarah, I.; McDonough, J. F.

    1981-08-01

    The effects of various parameters on an experimental concrete pavement were evaluated. Variables included in the pavement were (1) joint spacing, (2) subbase stabilization, (3) coating of dowel bars, (4) configuration of the saw cut, and (5) the use of skewed joints. Both long term and short term horizontal movements caused by temperature and vertical movement of slab ends under known axle loads were measured. A record of cracking and spalling of the pavement is also included. A statistical analysis of both long and short term movements was conducted and recommendations for joint design are included.

  13. Impacts of pavement types on in-vehicle noise and human health.

    PubMed

    Li, Qing; Qiao, Fengxiang; Yu, Lei

    2016-01-01

    Noise is a major source of pollution that can affect the human physiology and living environment. According to the World Health Organization (WHO), an exposure for longer than 24 hours to noise levels above 70 dB(A) may damage human hearing sensitivity, induce adverse health effects, and cause anxiety to residents nearby roadways. Pavement type with different roughness is one of the associated sources that may contribute to in-vehicle noise. Most previous studies have focused on the impact of pavement type on the surrounding acoustic environment of roadways, and given little attention to in-vehicle noise levels. This paper explores the impacts of different pavement types on in-vehicle noise levels and the associated adverse health effects. An old concrete pavement and a pavement with a thin asphalt overlay were chosen as the test beds. The in-vehicle noise caused by the asphalt and concrete pavements were measured, as well as the drivers' corresponding heart rates and reported riding comfort. Results show that the overall in-vehicle sound levels are higher than 70 dB(A) even at midnight. The newly overlaid asphalt pavement reduced in-vehicle noise at a driving speed of 96.5 km/hr by approximately 6 dB(A). Further, on the concrete pavement with higher roughness, driver heart rates were significantly higher than on the asphalt pavement. Drivers reported feeling more comfortable when driving on asphalt than on concrete pavement. Further tests on more drivers with different demographic characteristics, along highways with complicated configurations, and an examination of more factors contributing to in-vehicle noise are recommended, in addition to measuring additional physical symptoms of both drivers and passengers. While there have been many previous noise-related studies, few have addressed in-vehicle noise. Most studies have focused on the noise that residents have complained about, such as neighborhood traffic noise. As yet, there have been no complaints by

  14. Comparative field permeability measurement of permeable pavements using ASTM C1701 and NCAT permeameter methods.

    PubMed

    Li, Hui; Kayhanian, Masoud; Harvey, John T

    2013-03-30

    Fully permeable pavement is gradually gaining support as an alternative best management practice (BMP) for stormwater runoff management. As the use of these pavements increases, a definitive test method is needed to measure hydraulic performance and to evaluate clogging, both for performance studies and for assessment of permeability for construction quality assurance and maintenance needs assessment. Two of the most commonly used permeability measurement tests for porous asphalt and pervious concrete are the National Center for Asphalt Technology (NCAT) permeameter and ASTM C1701, respectively. This study was undertaken to compare measured values for both methods in the field on a variety of permeable pavements used in current practice. The field measurements were performed using six experimental section designs with different permeable pavement surface types including pervious concrete, porous asphalt and permeable interlocking concrete pavers. Multiple measurements were performed at five locations on each pavement test section. The results showed that: (i) silicone gel is a superior sealing material to prevent water leakage compared with conventional plumbing putty; (ii) both methods (NCAT and ASTM) can effectively be used to measure the permeability of all pavement types and the surface material type will not impact the measurement precision; (iii) the permeability values measured with the ASTM method were 50-90% (75% on average) lower than those measured with the NCAT method; (iv) the larger permeameter cylinder diameter used in the ASTM method improved the reliability and reduced the variability of the measured permeability. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Hydraulic design of pervious concrete highway shoulders

    NASA Astrophysics Data System (ADS)

    Grahl, Nathan Andrew

    Stormwater drainage has been a factor in roadway design for years. Now stormwater quantity and quality are also becoming regulated for roadways. As regulations of stormwater management continue to increase so does the need for more viable and effect management practices. The research presented and discussed in this thesis presents the option of using pervious concrete in highway shoulders as a best management practice for stormwater management. Research focused on the hydraulic response of pervious concrete pavements exposed to sheet flowing water. Pervious concrete samples were placed in a hydraulic flume to determine capture discharges, infiltration rates, and by-pass flowrates for a broad range of void contents, across a broad range of pavement cross slopes. The results demonstrate that the capture discharge and infiltration rates are inversely related to the cross slope of the pavement. Results also showed the infiltration rate of the permeable pavement exposed to sheet flowing water, in the model, is significantly lower than the measured infiltration rate. Pervious concrete samples were also tested to determine hydraulic response when exposed to clogging associated with sand used in roadway de-icing. The results of the clogging of the permeable pavements followed similar trends as the unclogged samples, with the only difference being a more significant reduction in infiltration rates at higher applications of sand. Preliminary discussion of a design methodology is included with a design example.

  16. Spills on Flat Inclined Pavements

    SciTech Connect

    Simmons, Carver S.; Keller, Jason M.; Hylden, Jeff L.

    2004-03-01

    This report describes the general spill phenomenology for liquid spills occurring on relatively impermeable surfaces such as concrete or asphalt pavement and the development and application of a model to describe the time evolution of such spills. The discussion assumes evaporation and degradation are negligible and a homogeneous surface. In such an instance, the inherent interfacial properties determine the spatial extent of liquid spreading with the initial flow being controlled by the release rate of the spill and by the liquids resistance to flow as characterized by its viscosity. A variety of spill scenarios were simulated and successful implementation of the model was achieved. A linear relationship between spill area and spill volume was confirmed. The simulations showed spill rate had little effect on the final spill area. Slope had an insignificant effect on the final spill area, but did modify spill shape considerably. However, a fluid sink on the edge of the simulation domain, representing a storm drain, resulted in a substantial decrease in spill area. A bona fide effort to determine the accuracy of the model and its calculations remain, but comparison against observations from a simple experiment showed the model to correctly determine the spill area and general shape under the conditions considered. Further model verification in the form of comparison against small scale spill experiments are needed to confirm the models validity.

  17. Leachability of dissolved chromium in asphalt and concrete surfacing materials.

    PubMed

    Kayhanian, Masoud; Vichare, Akshay; Green, Peter G; Harvey, John

    2009-08-01

    Leachate metal pollutant concentrations produced from different asphalt and concrete pavement surfacing materials were measured under controlled laboratory conditions. The results showed that, in general, the concentrations of most metal pollutants were below the reporting limits. However, dissolved chromium was detected in leachate from concrete (but not asphalt) specimens and more strongly in the early-time leachate samples. As the leaching continued, the concentration of Cr decreased to below or close to the reporting limit. The source of the chromium in concrete pavement was found to be cement. The concentration of total Cr produced from leachate of different cement coming from different sources that was purchased from retail distributors ranged from 124 to 641mug/L. This result indicates that the potential leachability of dissolved Cr from concrete pavement materials can be reduced through source control. The results also showed that the leachability of dissolved Cr in hardened pavement materials was substantially reduced. For example, the concentration of dissolved Cr measured in actual highway runoff was found to be much lower than the Cr concentration produced from leachate of both open and dense graded concrete pavement specimens under controlled laboratory study. It was concluded that pavement materials are not the source of pollutants of concern in roadway runoff; rather most pollutants in roadway surface runoff are generated from other road-use or land-use sources, or from (wet or dry) atmospheric deposition.

  18. Three Permeable Pavements Performances for Priority Metal Pollutants and Metals associated with Deicing Chemicals from Edison Parking Lot, NJ - abstract

    EPA Science Inventory

    The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements [permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA)]. Samples of each p...

  19. Three Permeable Pavements Performances for Priority Metal Pollutants and Metals Associated with Deicing Chemicals from Edison Parking Lot, NJ

    EPA Science Inventory

    The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements [permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA)]. Samples of each p...

  20. Three Permeable Pavements Performances for Priority Metal Pollutants and Metals Associated with Deicing Chemicals from Edison Parking Lot, NJ

    EPA Science Inventory

    The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements [permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA)]. Samples of each p...

  1. Three Permeable Pavements Performances for Priority Metal Pollutants and Metals associated with Deicing Chemicals from Edison Parking Lot, NJ - abstract

    EPA Science Inventory

    The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements [permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA)]. Samples of each p...

  2. General outlook of pavement and vehicle dynamics

    SciTech Connect

    Mamlouk, M.S.

    1997-11-01

    The interaction between vehicle and pavement is complex since pavement roughness excites the dynamic forces generated by vehicles, while these dynamic forces simultaneously increase the pavement roughness. The objective of this paper is to provide an overview of the results of recent research related to pavement and vehicle dynamics and their interaction and to evaluate their potential use in the design and management of pavements. Pavement dynamic models are capable of determining stresses, strains, and deflections in various directions when harmonic, pulse, or transient loads are applied. Vehicle dynamic models simulate the effect of pavement roughness on the inertia of various vehicle components. These models can predict the dynamic forces produced by different axles and wheels of traveling vehicles at different locations along the pavement. Pavement response computed using dynamic models matches field measurements closer than those computed using static models. The concept of vehicle-pavement interaction can be applied to weigh-in-motion, pavement design and performance, and vehicle regulations.

  3. Use of Ground Penetrating Radar at the FAA's National Airport Pavement Test Facility

    NASA Astrophysics Data System (ADS)

    Injun, Song

    2015-04-01

    The Federal Aviation Administration (FAA) in the United States has used a ground-coupled Ground Penetrating Radar (GPR) at the National Airport Pavement Test Facility (NAPTF) since 2005. One of the primary objectives of the testing at the facility is to provide full-scale pavement response and failure information for use in airplane landing gear design and configuration studies. During the traffic testing at the facility, a GSSI GPR system was used to develop new procedures for monitoring Hot Mix Asphalt (HMA) pavement density changes that is directly related to pavement failure. After reviewing current setups for data acquisition software and procedures for identifying different pavement layers, dielectric constant and pavement thickness were selected as dominant parameters controlling HMA properties provided by GPR. A new methodology showing HMA density changes in terms of dielectric constant variations, called dielectric sweep test, was developed and applied in full-scale pavement test. The dielectric constant changes were successfully monitored with increasing airplane traffic numbers. The changes were compared to pavement performance data (permanent deformation). The measured dielectric constants based on the known HMA thicknesses were also compared with computed dielectric constants using an equation from ASTM D4748-98 Standard Test Method for Determining the Thickness of Bound Pavement Layers Using Short-Pulse Radar. Six inches diameter cylindrical cores were taken after construction and traffic testing for the HMA layer bulk specific gravity. The measured bulk specific gravity was also compared to monitor HMA density changes caused by aircraft traffic conditions. Additionally this presentation will review the applications of the FAA's ground-coupled GPR on embedded rebar identification in concrete pavement, sewer pipes in soil, and gage identifications in 3D plots.

  4. Damage and healing evaluation of Mn/Road pavements using stress wave testing

    NASA Astrophysics Data System (ADS)

    Katzke, Evan; Kim, Y. R.

    1998-03-01

    In order to accurately assess the fatigue life of asphalt concrete pavements, an in-situ field evaluation method must be used so that factors which cannot be accounted for in the lab are considered. Surface wave testing is employed in this research to nondestructively monitor sensitive structural changes in the asphalt surface layer of pavements in the field. Microcrack damage growth and healing are investigated on pavement test sections at the Minnesota Road Research Facility (Mn/Road) by way of surface wave testing. One of the mechanisms which cannot be simulated accurately in the lab is healing of asphalt concrete during rest periods. Healing of the asphalt pavement test sections at Mn/Road following a 24 hour rest period was quantified using wavespeed measurements. These measurements show that a significant amount of healing is occurring and can be detected using stress wave testing. Several signal processing methods are used to evaluate the microcrack damage growth and healing in the asphalt pavement sections. The 'apparent' modulus is computed from the velocity of wave propagation and used to quantify damage in the pavements. Attenuation of the stress waves is also calculated for damage assessment. It is discovered that attenuation parameters in the frequency domain are more sensitive than wavespeed calculations in the time domain, but contain significantly more variability.

  5. Geotextiles in Flexible Pavement Construction

    ERIC Educational Resources Information Center

    Alungbe, Gabriel D.

    2004-01-01

    People everywhere in the developed world regularly drive on paved roads. Learning about the construction techniques and materials used in paving benefits technology and construction students. This article discusses the use of geosynthetic textiles in pavement construction. It presents background on pavements and describes geotextiles and drainage…

  6. Geotextiles in Flexible Pavement Construction

    ERIC Educational Resources Information Center

    Alungbe, Gabriel D.

    2004-01-01

    People everywhere in the developed world regularly drive on paved roads. Learning about the construction techniques and materials used in paving benefits technology and construction students. This article discusses the use of geosynthetic textiles in pavement construction. It presents background on pavements and describes geotextiles and drainage…

  7. Effects on evaporation rates from different water-permeable pavement designs.

    PubMed

    Starke, P; Göbel, P; Coldewey, W G

    2011-01-01

    The urban water balance can be attenuated to the natural by water-permeable pavements (WPPs). Furthermore, WPPs have a 16% higher evaporation rate than impermeable pavements, which can lead to a better urban climate. Evaporation rates from pavements are influenced by the pavement surface and by the deeper layers. By a compared evaporation measurement between different WPP designs, the grain size distribution of the sub-base shows no influence on the evaporation rates in a significant way. On the contrary, a sub-base made of a twin-layer decreases the evaporation by 16% compared to a homogeneous sub-base. By a change in the colour of the paving stone, 19% higher evaporation rates could be achieved. A further comparison shows that the transpiration-effect of the grass in grass pavers increases the evaporation rates more than threefold to pervious concrete pavements. These high evapotranspiration rates can not be achieved with a pervious concrete paving stone. In spite of this, the broad field of application of the pervious concrete paving stone increases the importance in regard to the urban climate.

  8. Nutrient infiltrate concentrations from three permeable pavement types.

    PubMed

    Brown, Robert A; Borst, Michael

    2015-12-01

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha parking lot in Edison, New Jersey, that incorporated permeable interlocking concrete pavement (PICP), pervious concrete (PC), and porous asphalt (PA). Each permeable pavement type has four, 54.9-m(2), lined sections that direct all infiltrate into 5.7-m(3) tanks enabling complete volume collection and sampling. This paper highlights the results from a 12-month period when samples were collected from 13 rainfall/runoff events and analyzed for nitrogen species, orthophosphate, and organic carbon. Differences in infiltrate concentrations among the three permeable pavement types were assessed and compared with concentrations in rainwater samples and impervious asphalt runoff samples, which were collected as controls. Contrary to expectations based on the literature, the PA infiltrate had significantly larger total nitrogen (TN) concentrations than runoff and infiltrate from the other two permeable pavement types, indicating that nitrogen leached from materials in the PA strata. There was no significant difference in TN concentration between runoff and infiltrate from either PICP or PC, but TN in runoff was significantly larger than in the rainwater, suggesting meaningful inter-event dry deposition. Similar to other permeable pavement studies, nitrate was the dominant nitrogen species in the infiltrate. The PA infiltrate had significantly larger nitrite and ammonia concentrations than PICP and PC, and this was presumably linked to unexpectedly high pH in the PA infiltrate that greatly exceeded the optimal pH range for nitrifying bacteria. Contrary to the nitrogen results, the PA infiltrate had significantly smaller orthophosphate concentrations than in rainwater, runoff, and infiltrate from PICP

  9. Fore and aft elastic response characteristics of 34 x 9.9, type 7, 14 ply-rating aircraft tires of bias-ply, bias-belted, and radial-belted design. M.S. Thesis - George Washington Univ., May 1973; [static and rolling tests on dry concrete pavements

    NASA Technical Reports Server (NTRS)

    Tanner, J. A.

    1974-01-01

    An investigation was conducted to determine the fore-and-aft elastic response characteristics of 34 x 9.9, type VII, 14 ply-rating aircraft tires of bias-ply, bias-belted, and radial-belted design. The investigation consisted of static and rolling tests on dry concrete pavements at the Langley aircraft landing loads and traction facility; statistical techniques which related the measured tire elastic characteristics to variations in the vertical load, inflation pressure, braking force and/or tire vertical deflection; and a semiempirical analysis which related the tire elastic behavior to measured wheel slippage during steady-state braking. The bias-belted tire developed the largest spring constant value for most loading conditions; the radial-belted tire, the smallest. The elastic response of the tire free periphery to static braking included both tread stretch and carcass torsional wind-up about the axle for the bias-ply and bias-belted tires and carcass wind-up alone for the radial-belted tire.

  10. Pavement recycling. Executive summary and report

    SciTech Connect

    1995-10-01

    The Federal Highway Administration (FHWA) initiated Demonstration Project 39 (DP 39) Recycling Asphalt Pavements in June 1976. The project showed that asphalt pavement recycling was a technically viable rehabitation technique, and it was estimated that the use of reclaimed asphalt pavement (RAP) would amount to approximately 15 percent of the total hot-mix asphalt (HMA) production by the mid-1980s. It was expected that most of the asphalt pavement removed would be reused in new pavement construction or overlays.

  11. 9 CFR 91.26 - Concrete flooring.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... aboard an ocean vessel shall have a 3 inch concrete pavement, proportioned and mixed to give 2000 psi... composite material diagonally scored one-half inch deep may be used on iron decks instead of wooden flooring... aft with flat side down, and so placed as to provide in-between spaces of 12, 14, 26, and 14 inches...

  12. 9 CFR 91.26 - Concrete flooring.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... aboard an ocean vessel shall have a 3 inch concrete pavement, proportioned and mixed to give 2000 psi... composite material diagonally scored one-half inch deep may be used on iron decks instead of wooden flooring... aft with flat side down, and so placed as to provide in-between spaces of 12, 14, 26, and 14 inches...

  13. 9 CFR 91.26 - Concrete flooring.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... aboard an ocean vessel shall have a 3 inch concrete pavement, proportioned and mixed to give 2000 psi... composite material diagonally scored one-half inch deep may be used on iron decks instead of wooden flooring... aft with flat side down, and so placed as to provide in-between spaces of 12, 14, 26, and 14 inches...

  14. Fatigue of concrete subjected to biaxial loading in the tension region

    NASA Astrophysics Data System (ADS)

    Subramaniam, Kolluru V. L.

    Rigid airport pavement structures are subjected to repeated high-amplitude loads resulting from passing aircraft. The resulting stress-state in the concrete is a biaxial combination of compression and tension. It is of interest to model the response of plain concrete to such loading conditions and develop accurate fatigue-based material models for implementation in mechanistic pavement design procedures. The objective of this work is to characterize the quasi-static and low-cycle fatigue response of concrete subjected to biaxial stresses in the tensile-compression-tension (t-C-T) region, where the principal tensile stress is larger in magnitude than the principal compressive stress. An experimental investigation of material behavior in the biaxial t-C-T region is conducted. The experimental setup consists of the following test configurations: (a) notched concrete beams tested in three-point bend configuration, and (b) hollow concrete cylinders subjected to torsion with or without superimposed axial tensile force. The damage imparted to the material is examined using mechanical measurements and an independent nondestructive evaluation (NDE) technique based on vibration measurements. The failure of concrete in t-C-T region is shown to be a local phenomenon under quasi-static and fatigue loading, wherein the specimen fails owing to a single crack. The crack propagation is studied using the principles of fracture mechanics. It is shown that the crack propagation resulting from the t-C-T loading can be predicted using mode I fracture parameters. It is observed that crack growth in constant amplitude fatigue loading is a two-phase process: a deceleration phase followed by an acceleration stage. The quasi-static load envelope is shown to predict the crack length at fatigue failure. A fracture-based fatigue failure criterion is proposed, wherein the fatigue failure can be predicted using the critical mode I stress intensity factor. A material model for the damage evolution

  15. How Concrete Is Concrete?

    ERIC Educational Resources Information Center

    Gravemeijer, Koeno

    2011-01-01

    If we want to make something concrete in mathematics education, we are inclined introduce, what we call, "manipulatives", in the form of tactile objects or visual representations. If we want to make something concrete in a everyday-life conversation, we look for an example. In the former, we try to make a concrete model of our own,…

  16. Technical Note: Outlays on Construction of Airport Runways with Prestressed and Dowelled Pavements

    NASA Astrophysics Data System (ADS)

    Więckowski, Andrzej; Sznurawa, Alicja

    2015-09-01

    For two variants of runways with abrasive concrete pavements in the prestressed and dowelled technologies, analyses have been presented regarding labour, materials, use of machinery, and financial outlays, together with the necessary technological-organisational analyses and assessment of work execution cycles, by the example of construction of a runway at the Katowice Airport.

  17. Methods to Use Surface Infiltration Tests in Permeable Pavement Systems to Determine Maintenance Frequency

    EPA Science Inventory

    Currently, there is limited guidance on selecting test sites to measure surface infiltration rates in permeable pavement systems to determine maintenance frequency. The ASTM method (ASTM C1701) for measuring infiltration rate of in-place pervious concrete suggest to either (1) p...

  18. Methods to Use Surface Infiltration Tests in Permeable Pavement Systems to Determine Maintenance Frequency

    EPA Science Inventory

    Currently, there is limited guidance on selecting test sites to measure surface infiltration rates in permeable pavement systems to determine maintenance frequency. The ASTM method (ASTM C1701) for measuring infiltration rate of in-place pervious concrete suggest to either (1) p...

  19. Mechanics based model for predicting structure-induced rolling resistance (SRR) of the tire-pavement system

    NASA Astrophysics Data System (ADS)

    Shakiba, Maryam; Ozer, Hasan; Ziyadi, Mojtaba; Al-Qadi, Imad L.

    2016-11-01

    The structure-induced rolling resistance of pavements, and its impact on vehicle fuel consumption, is investigated in this study. The structural response of pavement causes additional rolling resistance and fuel consumption of vehicles through deformation of pavement and various dissipation mechanisms associated with inelastic material properties and damping. Accurate and computationally efficient models are required to capture these mechanisms and obtain realistic estimates of changes in vehicle fuel consumption. Two mechanistic-based approaches are currently used to calculate vehicle fuel consumption as related to structural rolling resistance: dissipation-induced and deflection-induced methods. The deflection-induced approach is adopted in this study, and realistic representation of pavement-vehicle interactions (PVIs) is incorporated. In addition to considering viscoelastic behavior of asphalt concrete layers, the realistic representation of PVIs in this study includes non-uniform three-dimensional tire contact stresses and dynamic analysis in pavement simulations. The effects of analysis type, tire contact stresses, pavement viscoelastic properties, pavement damping coefficients, vehicle speed, and pavement temperature are then investigated.

  20. Preliminary evaluation of the lifecycle costs and market barriers of reflective pavements

    SciTech Connect

    Ting, M.; Koomey, J.G.; Pomerantz, M.

    2001-11-21

    The objective of this study is to evaluate the life cycle costs and market barriers associated with using reflective paving materials in streets and parking lots as a way to reduce the urban heat island effect. We calculated and compared the life cycle costs of conventional asphalt concrete (AC) pavements to those of other existing pavement technologies with higher reflectivity-portland cement concrete (PCC), porous pavements, resin pavements, AC pavements using light-colored chip seals, and AC pavements using light-colored asphalt emulsion additives. We found that for streets and parking lots, PCC can provide a cost-effective alternative to conventional AC when severely damaged pavements must be completely reconstructed. We also found that rehabilitating damaged AC streets and intersections with thin overlays of PCC (ultra-thin white topping) can often provide a cost-effective alternative to standard rehabilitation techniques using conventional AC. Chip sealing is a common maintenance treatment for low-volume streets which, when applied using light-colored chips, could provide a reflective pavement surface. If the incremental cost of using light-colored chips is low, this chip sealing method could also be cost-effective, but the incremental costs of light-colored chips are as of yet uncertain and expected to vary. Porous pavements were found to have higher life cycle costs than conventional AC in parking lots, but several cost-saving features of porous pavements fell outside the boundaries of this study. Resin pavements were found to be only slightly more expensive than conventional AC, but the uncertainties in the cost and performance data were large. The use of light-colored additives in asphalt emulsion seal coats for parking lot pavements was found to be significantly more expensive than conventional AC, reflecting its current niche market of decorative applications. We also proposed two additional approaches to increasing the reflectivity of conventional AC

  1. Permanent deformation of flexible pavements

    NASA Astrophysics Data System (ADS)

    Brown, S. F.; Broderick, B. V.; Pappin, J. W.

    1980-06-01

    Seven pairs of pavements with granular bases were tested under controlled conditions. One pavement in each pair contained fabric inclusions. An improved testing facility was developed, including: (1) servo-hydraulic system for the loading carriage; (2) amplification and read-out system for pressure cells; (3) linearizing unit for strain coils; (4) transducers for measuring vertical and resilient deflection; (5) techniques for measuring in situ strain on fabric inclusions; (6) extensive use of nuclear density meter to monitor pavement and foundation materials. The following conclusions are drawn: (1) No improvement in performance resulted from fabric inclusions. (2) No consistent reduction in in-situ stresses, resilient strains, or permanent strains was observed as a result of fabric inclusion. (3) No consistent improvement in densities resulted from fabric inclusions. (4) Some slip apparently occurred between fabric and soil on those pavements which involved large deformations. The slip occurred between fabric and crushed limestone base rather than between fabric and silty-clay subgrade.

  2. Cohesive fracture model for functionally graded fiber reinforced concrete

    SciTech Connect

    Park, Kyoungsoo; Paulino, Glaucio H.; Roesler, Jeffery

    2010-06-15

    A simple, effective, and practical constitutive model for cohesive fracture of fiber reinforced concrete is proposed by differentiating the aggregate bridging zone and the fiber bridging zone. The aggregate bridging zone is related to the total fracture energy of plain concrete, while the fiber bridging zone is associated with the difference between the total fracture energy of fiber reinforced concrete and the total fracture energy of plain concrete. The cohesive fracture model is defined by experimental fracture parameters, which are obtained through three-point bending and split tensile tests. As expected, the model describes fracture behavior of plain concrete beams. In addition, it predicts the fracture behavior of either fiber reinforced concrete beams or a combination of plain and fiber reinforced concrete functionally layered in a single beam specimen. The validated model is also applied to investigate continuously, functionally graded fiber reinforced concrete composites.

  3. Guidelines and specifications for the use of reclaimed aggregates in pavement. Final report

    SciTech Connect

    Chini, S.A.; Kuo, S.S.; Duxbury, J.P.; Monteiro, F.M.B.R.; Mbwambo, W.J.

    1998-08-01

    The project focused on evaluating the performance of recycled concrete for use as a base material under hot mix asphalt pavements and as an aggregate in Portland cement concrete pavements. In order to meet this objective, several goals were established. First, published literature on RCA was reviewed and a survey of State Highway Agencies (SHA) was performed to determine the extent of use of RCA in highway projects. Second, the RCA was tested at the FDOT Material Lab in Gainesville, Florida, to determine the material properties. Third, by using the output from the falling weight deflectometer test along with the KENSLABS and KENLAYER computer programs (Huang, 1993), a theoretical analysis was performed to predict the number of repetitions before the pavements failed in both the fatigue and permanent deformation criteria. Lastly, nine design sections involving HMA and PCC pavements were constructed at the University of Central Florida`s Circular Accelerated Test Track (UCF-CATT) to evaluate the response of the pavement sections made with RCA under actual dual-wheel loading.

  4. Field validation of road roughness evaluation using in-pavement strain sensors

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Deng, F.; Huang, Y.; Bridgelall, R.

    2016-04-01

    Most transportation agencies now collect pavement roughness data using the inertial profilers, which requires instrumented vehicles and technicians with specialized training to interpret the results. The extensive labor requirements of the profiling activities limit data collection for portions of the national highway system to at most once per year, resulting in outdated roughness data for decision making of maintenance needs. In this paper, a real-time roughness evaluation method was developed by linking the output of durable in-pavement strain sensors to road roughness level. The durable in-pavement sensors will continuously provide information of road roughness in real time after they are installed and calibrated during the road construction until the service life of the associated pavement. Field tests validated the developed strain method by comparison with standard inertial profiling method and the connected-vehicle method. The comparison of the results from the field tests approves the effectiveness of the developed road roughness evaluation method using in-pavement strain sensors, which can be further applied practically for needed concrete pavements.

  5. Durable high strength cement concrete topping for asphalt roads

    NASA Astrophysics Data System (ADS)

    Vyrozhemskyi, Valerii; Krayushkina, Kateryna; Bidnenko, Nataliia

    2017-09-01

    Work on improving riding qualities of pavements by means of placing a thin cement layer with high roughness and strength properties on the existing asphalt pavement were conducted in Ukraine for the first time. Such pavement is called HPCM (High Performance Cementitious Material). This is a high-strength thin cement-layer pavement of 8-9 mm thickness reinforced with metal or polymer fiber of less than 5 mm length. Increased grip properties are caused by placement of stone material of 3-5 mm fraction on the concrete surface. As a result of the research, the preparation and placement technology of high-strength cement thin-layer pavement reinforced with fiber was developed to improve friction properties of existing asphalt pavements which ensures their roughness and durability. It must be emphasized that HPCM is a fundamentally new type of thin-layer pavement in which a rigid layer of 10 mm thickness is placed on a non-rigid base thereby improving riding qualities of asphalt pavement at any season of a year.

  6. Analysis of Instrumentation Selection and Placement to Monitor the Hydrologic Performance of Permeable Pavement Systems and Bioinfiltration Areas at the Edison Environmental Center in New Jersey

    EPA Science Inventory

    In 2009, the U.S. Environmental Protection Agency constructed a 0.4-ha (1-ac) parking lot surfaced with three different permeable pavement types (interlocking concrete pavers, porous concrete, and porous asphalt) and six bioinfiltration areas with three different drainage area to...

  7. Analysis of Instrumentation Selection and Placement to Monitor the Hydrologic Performance of Permeable Pavement Systems and Bioinfiltration Areas at the Edison Environmental Center in New Jersey

    EPA Science Inventory

    In 2009, the U.S. Environmental Protection Agency constructed a 0.4-ha (1-ac) parking lot surfaced with three different permeable pavement types (interlocking concrete pavers, porous concrete, and porous asphalt) and six bioinfiltration areas with three different drainage area to...

  8. Acidalia Plain

    NASA Image and Video Library

    2006-05-03

    This MOC image shows a relatively flat plain in Acidalia Planitia. The circular feature near the left west edge is the surface manifestation of a buried impact crater, a common feature observed on the northern plains of Mars

  9. Quantifying Evaporation in a Permeable Pavement System

    EPA Science Inventory

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. Th...

  10. Quantifying Evaporation in a Permeable Pavement System

    EPA Science Inventory

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. Th...

  11. Criteria for the Use of Lime-Cement-Flyash on Airport Pavements

    DTIC Science & Technology

    1989-12-01

    drainage of the pavement system. Performance of pavement with I.F as a base/subbase has been studied by the FAA2 2 and others. 6,8,15,21,27,28 They...conditions of soil classification, drainage and frost, a subbase is not required. The concrete surface must provide an acceptable nonskid surface...1965). 17. Callahan, J.P., Morrow, J., and Ahlberg, H.L., " Autogenous Healing in Lime-Pozzolan-Aggregate Mixtures," Report No. 631. Department of

  12. The use of reflective and permeable pavements as a potential practice for heat island mitigation and stormwater management

    NASA Astrophysics Data System (ADS)

    Li, H.; Harvey, J. T.; Holland, T. J.; Kayhanian, M.

    2013-03-01

    To help address the built environmental issues of both heat island and stormwater runoff, strategies that make pavements cooler and permeable have been investigated through measurements and modeling of a set of pavement test sections. The investigation included the hydraulic and thermal performance of the pavements. The permeability results showed that permeable interlocking concrete pavers have the highest permeability (or infiltration rate, ˜0.5 cm s-1). The two permeable asphalt pavements showed the lowest permeability, but still had an infiltration rate of ˜0.1 cm s-1, which is adequate to drain rainwater without generating surface runoff during most typical rain events in central California. An increase in albedo can significantly reduce the daytime high surface temperature in summer. Permeable pavements under wet conditions could give lower surface temperatures than impermeable pavements. The cooling effect highly depends on the availability of moisture near the surface layer and the evaporation rate. The peak cooling effect of watering for the test sections was approximately 15-35 °C on the pavement surface temperature in the early afternoon during summer in central California. The evaporative cooling effect on the pavement surface temperature at 4:00 pm on the third day (25 h after watering) was still 2-7 °C lower compared to that on the second day, without considering the higher air temperature on the third day. A separate and related simulation study performed by UCPRC showed that full depth permeable pavements, if designed properly, can carry both light-duty traffic and certain heavy-duty vehicles while retaining the runoff volume captured from an average California storm event. These preliminarily results indicated the technical feasibility of combined reflective and permeable pavements for addressing the built environment issues related to both heat island mitigation and stormwater runoff management.

  13. Theoretical Solution for Temperature Profile in Multi-layered Pavement Systems Subjected to Transient Thermal Loads

    DTIC Science & Technology

    2011-01-01

    kcal/mm s ◦C) Geopolymer paste 2.0x10−7 PCC slab 5.1x10−7 Thermal diffusivity, α (mm2/s) Geopolymer 0.2 PCC slab 1.3 for the surface layer of airfield...concrete pavements. Geopolymer materials have desirable properties for serving as an alternative binder to traditional Portland cement in producing...high thermal stability. Thus it is possible to construct paving concrete made from a geopolymer binder on top of the ordinary concrete slab to limit

  14. Electrical resistance of carbon-nanofiber concrete

    NASA Astrophysics Data System (ADS)

    Gao, Di; Sturm, Mariel; Mo, Y. L.

    2009-09-01

    Concrete is the most widely used construction material, and carbon nanofibers have many advantages in both mechanical and electrical properties such as high strength, high Young's modulus and high conductivity. In this paper, the mechanical and electrical properties of concrete containing carbon nanofibers (CNF) are experimentally studied. The test results indicate that the compressive strength and per cent reduction in electrical resistance while loading concrete containing CNF are much greater than those of plain concrete. Finally, a reasonable concentration of CNF is obtained for use in concrete which not only enhances compressive strength, but also improves the electrical properties required for strain monitoring, damage evaluation and self-health monitoring of concrete.

  15. 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.

  16. Degradation Modeling of Polyurea Pavement Markings

    DTIC Science & Technology

    2011-03-01

    DEGRADATION MODELING OF POLYUREA PAVEMENT MARKINGS THESIS Jonathan D. Needham, Captain, USAF AFIT/GEM/ENV/11-M05 DEPARTMENT OF THE...DEGRADATION MODELING OF POLYUREA PAVEMENT MARKINGS THESIS Presented to the Faculty Department of Engineering Management Graduates School of...DEGRADATION MODELING OF POLYUREA PAVEMENT MARKINGS Jonathan D. Needham, BS Captain, USAF Approved

  17. Impact of pavement conditions on crash severity.

    PubMed

    Li, Yingfeng; Liu, Chunxiao; Ding, Liang

    2013-10-01

    Pavement condition has been known as a key factor related to ride quality, but it is less clear how exactly pavement conditions are related to traffic crashes. The researchers used Geographic Information System (GIS) to link Texas Department of Transportation (TxDOT) Crash Record Information System (CRIS) data and Pavement Management Information System (PMIS) data, which provided an opportunity to examine the impact of pavement conditions on traffic crashes in depth. The study analyzed the correlation between several key pavement condition ratings or scores and crash severity based on a large number of crashes in Texas between 2008 and 2009. The results in general suggested that poor pavement condition scores and ratings were associated with proportionally more severe crashes, but very poor pavement conditions were actually associated with less severe crashes. Very good pavement conditions might induce speeding behaviors and therefore could have caused more severe crashes, especially on non-freeway arterials and during favorable driving conditions. In addition, the results showed that the effects of pavement conditions on crash severity were more evident for passenger vehicles than for commercial vehicles. These results provide insights on how pavement conditions may have contributed to crashes, which may be valuable for safety improvement during pavement design and maintenance. Readers should notice that, although the study found statistically significant effects of pavement variables on crash severity, the effects were rather minor in reality as suggested by frequency analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Pavement thickness evaluation using ground penetrating radar

    NASA Astrophysics Data System (ADS)

    Harris, Dwayne Arthur

    Accurate knowledge of pavement thickness is important information to have both at a network and project level. This information aids in pavement management and design. Much of the time this information is missing, out of date, or unknown for highway sections. Current technologies for determining pavement thickness are core drilling, falling weight deflectometer (FWD), and ground penetrating radar (GPR). Core drilling provides very accurate pin point pavement thickness information; however, it is also time consuming, labor intensive, intrusive to traffic, destructive, and limited in coverage. FWD provides nondestructive estimates of both a surface thickness and total pavement structure thickness, including pavement, base and sub-base. On the other hand, FWD is intrusive to traffic and affected by the limitations and assumptions the method used to estimate thickness. GPR provides pavement surface course thickness estimates with excellent data coverage at highway speed. Yet, disadvantages include the pavement thickness estimation being affected by the electrical properties of the pavement, limitations of the system utilized, and heavy post processing of the data. Nevertheless, GPR has been successfully utilized by a number of departments of transportation (DOTs) for pavement thickness evaluation. This research presents the GPR thickness evaluation methods, develops GPRPAVZ the software used to implement the methodologies, and addresses the quality of GPR pavement thickness evaluation.

  19. Mechanistic interpretation of nondestructive pavement testing deflections

    NASA Astrophysics Data System (ADS)

    Hoffman, M. S.

    1980-06-01

    A method is proposed for the backcalculation of material properties in flexible pavements based on the interpretation of surface deflection measurements. ILLI-PAVE, a stress dependent finite element pavement model, was used to generate data for developing algorithms and nomographs for deflection basin interpretation. Over 11,000 deflection measurements for 24 different flexible pavement sections were collected and analyzed. Deflections were measured using the Benkelman Beam, the IDOT Road Rater, the Falling Weight Deflectometer, and an accelerometer to measure deflections under moving trucks. Loading mode effects on pavement response were investigated using dynamic and viscous pavement models. The factors controlling the pavement response to different loading modes were explained and identified. Correlations between different devices were developed. The proposed evaluation procedure is illustrated for three different flexible pavements using deflection data collected on several testing dates.

  20. Teaching Methodology of Flexible Pavement Materials and Pavement Systems

    ERIC Educational Resources Information Center

    Mehta, Yusuf; Najafi, Fazil

    2004-01-01

    Flexible pavement materials exhibit complex mechanical behavior, in the sense, that they not only show stress and temperature dependency but also are sensitive to moisture conditions. This complex behavior presents a great challenge to the faculty in bringing across the level of complexity and providing the concepts needed to understand them. The…

  1. Examples of cooler reflective streets for urban heat-island mitigation : Portland cement concrete and chip seals

    SciTech Connect

    Pomerantz, M.; Akbari, H.; Chang, S.-C.; Levinson, R.; Pon, B.

    2003-04-30

    Part of the urban heat island effect can be attributed to dark pavements that are commonly used on streets and parking lots. In this paper we consider two light colored, hence cooler, alternative paving materials that are in actual use in cities today. These are Portland cement concrete (PCC) pavements and chip seals. We report measurements of the albedos of some PCC and chip sealed pavements in the San Francisco Bay Area. The albedos of the PCC pavements ranged from about 0.18 to 0.35. The temperatures of some PCC pavements are also measured and calculated. We then consider how the albedos of the constituent materials of the PCC (stone, sand and cement) contribute to the albedos of the resulting finished concrete. The albedos of a set of chip sealed pavements in San Jose, CA, were measured and correlated with the times of their placement. It is found that the albedos decrease with age (and use) but remain higher than that of standard asphalt concrete (AC) for about five years. After t hat, the albedos of the chip seals are about 0.12, similar to aged AC. The fact that many PCC pavements have albedos at least twice as high as aged AC suggests that it is possible to have pavement albedos that remain high for many years.

  2. Influence of mixture composition on the noise and frictional characteristics of flexible pavements

    NASA Astrophysics Data System (ADS)

    Kowalski, Karol J.

    Both traffic noise and wet pavement-tire friction are mainly affected by the tire/pavement interaction. Existing laboratory test methods allow for evaluation of polishing resistance of the aggregates only. Currently, there is no generally accepted standardized laboratory test method to address noise related issues and the overall frictional properties of pavements (including macrotexture). In this research, which included both laboratory and field components, friction and noise properties of the flexible (asphalt) pavements were investigated. As a part of this study, a laboratory device to polish asphalt specimens was developed and the procedure to evaluate mixture frictional properties was proposed. Following this procedure, forty-six different Superpave mixtures (each utilizing a different aggregate blends), one stone matrix asphalt (SMA) mixture and one porous friction course (PFC) mixture were tested. Six of the above mixes (four Superpave mixtures, SMA mixture and PFC mixture) were selected for laboratory noise testing. This testing was performed using a one-of-a-kind tester called the Tire/Pavement Test Apparatus (TPTA). In addition, the field sections constructed using Superpave, SMA and PFC mixtures were also periodically tested for friction and noise. Field measurements included testing of total of 23 different asphalt and two concrete pavements. The field friction testing was performed using both portable CTM and DFT devices and the (ASTM E 274) locked wheel friction trailer. The laboratory friction testing was performed using CTM and DFT devices only. The results of both field and laboratory friction measurements were used to develop an International Friction Index (IFI)-based frictional requirement for laboratory friction measurements. The results collected in the course of the study indicate that the IFI-based flag values could be successfully used in place of SN-based flag values to characterize frictional characteristics of pavements.

  3. Research on tensile strength characteristics of bridge deck pavement bonding layers

    NASA Astrophysics Data System (ADS)

    Wu, Shaopeng; Han, Jun

    2009-12-01

    As the development of the traffic in the world, the bridge deck pavement is playing a more and more important role in the whole traffic system. Big span bridge has become more and more especially cement concrete bridge, therefore the bridge deck pavement bonding layers are emphasized as an important part of bridge traffic system, which can mitigate travel impact to bridge and magnify stationary or traffic amenity. The quality and durability of deck pavement bonding layer has directly effect on traffic safety, comfort, durability and investment of bridge. It represents the first line of defence against the ingress of water, road de-icing salts and aggressive chemicals. In real project, many early age damage of bridge deck pavement has become serious disease that affecting the function of bridge. During the construction of the bridge deck, many types of asphalt binders were used, such as styrene-butadiene-styrene (SBS) modified asphalt, styrene-butadiene rubber (SBR) modified asphalt, neoprene latex asphalt, etc. In this paper UTM-25 was used to test the tensile strength of different bridge deck pavement bonding layers with the different treatment methods to inter-surface.

  4. Research on tensile strength characteristics of bridge deck pavement bonding layers

    NASA Astrophysics Data System (ADS)

    Wu, Shaopeng; Han, Jun

    2010-03-01

    As the development of the traffic in the world, the bridge deck pavement is playing a more and more important role in the whole traffic system. Big span bridge has become more and more especially cement concrete bridge, therefore the bridge deck pavement bonding layers are emphasized as an important part of bridge traffic system, which can mitigate travel impact to bridge and magnify stationary or traffic amenity. The quality and durability of deck pavement bonding layer has directly effect on traffic safety, comfort, durability and investment of bridge. It represents the first line of defence against the ingress of water, road de-icing salts and aggressive chemicals. In real project, many early age damage of bridge deck pavement has become serious disease that affecting the function of bridge. During the construction of the bridge deck, many types of asphalt binders were used, such as styrene-butadiene-styrene (SBS) modified asphalt, styrene-butadiene rubber (SBR) modified asphalt, neoprene latex asphalt, etc. In this paper UTM-25 was used to test the tensile strength of different bridge deck pavement bonding layers with the different treatment methods to inter-surface.

  5. Research on construction technology for orthotropic steel deck pavement of Haihe River Chunyi Bridge

    NASA Astrophysics Data System (ADS)

    Xue, Y. C.; Qian, Z. D.; Zhang, M.

    2017-01-01

    In order to ensure the good service quality of orthotropic steel deck pavement of Haihe River Chunyi Bridge in Tianjin, and to reduce the occurrence of pavement diseases like lateral and longitudinal cracks, the key working procedures such as steel deck cleaning, anticorrosive coating, bonding layer spraying, seam cutting, epoxy asphalt concrete’s mixing, transportation, paving and compaction were studied. The study was based on the main features of epoxy asphalt concrete which is the pavement materials of Haihe River Chunyi Bridge, and combined with the basic characteristics and construction conditions of Haihe River Chunyi Bridge. Furthermore, some processing measures like controlling time and temperature, continuous paving with two pavers, lateral feeding, and improving the compaction method were proposed. The project example shows that the processing measures can effectively solve the technical difficulties in the construction of orthotropic steel deck pavement of Haihe River Chunyi Bridge, can greatly improve the construction speed and quality, and can provide reference for the same kinds of orthotropic steel deck pavement construction.

  6. State-of-the-art review of the applications of nanotechnology in pavement materials

    NASA Astrophysics Data System (ADS)

    Castillo, Luis, Jr.

    The use of nanotechnology in pavement materials is one main area that shows great promise and has the potential to change commonly used materials. This will develop more effective solutions to achieve the desired performance. The overall objective of this work is to present a state-of-the-art literature review of nano-science-based principles to improve the performance and, ultimately, the life cycle of transportation construction materials. This work will be organized into two different parts. The first part will consist of six sections: applications of nanotechnology in concrete pavements, applications of nanotechnology in asphalt pavement, application of nanotechnology in general soils, cost-benefit analysis, challenges, and trends to the future. In addition, a current practice review was performed from a literature review that included a questionnaire of the knowledge and opinion about nanotechnology, which included students, general contractors, teachers, engineers, and architects. The second part will deal with the advancement of the application of nanotechnology in pavement materials for different developed countries. Because nanotechnology is relatively a young field in pavement materials, limited research has been conducted in North America, Europe, and Asia. A comparison of the advancement of nano-science-based principles, as applied to the performance and life cycle of transportation materials, for the three continents will be carried out in a summarized manner.

  7. Smooth brome (Bromus inermis Leyss) response to concrete grinding residue application

    USDA-ARS?s Scientific Manuscript database

    Concrete grinding residue (CGR) is a slurry byproduct created by concrete pavement maintenance operations. The application of CGR to roadside soils is not consistently regulated by state agencies across the United States. Much of this variability in regulation may be due to the lack of science-base...

  8. Comparative study of nondestructive pavement testing, WES (Waterways Experiment Station) NDT (nondestructive tests) methodologies

    NASA Astrophysics Data System (ADS)

    Hall, J. W.; Alelxander, D. R.

    1985-09-01

    A demonstration of nondestructive airfield pavement evaluation procedures conducted by the US Army Engineer Waterways Experiment Station (WES) using both the WES 16-kip vibrator and a Dynatest falling weight deflectometer (FWD) is described. The nondestructive tests (NDT) were conducted at MacDill Air Force Base on five pavement test areas consisting of asphaltic concrete, portland cement concrete, and composite pavements. Two methods of data analysis were used. The dynamic stiffness modulus (DMS) method used dynamic deflection data from the WES 16-kip vibrator with a correlation analysis developed a number of years ago by WES. This method uses a correlation between the DSM (a load-deflection ratio) and the allowable load on a single wheel as derived from traditional test pit methods. The second analysis scheme used measured deflection basins at the pavement surface and layered elastic theory. Elastic moduli are computed by matching measured deflection basins with computed basins. Limiting stress/strain is then used to compute allowable aircraft loadings. This method was used with data from both the WES 16-kip vibrator and the FWD. Also demonstrated was a method of determining joint load transfer and of making appropriate adjustments to the allowable load to account for lack of load transfer.

  9. Development of a Pavement Maintenance Management System. Volume 10. Summary of Development from 1974 through 1983

    DTIC Science & Technology

    1984-07-01

    load-carrying capacity, hydroplaning potential, previous M&R, and past/current/future traffic, mission, and costs. M&R guidelines were developed for...requirements would have necessitated diverting aircraft to other airfields, which would have cost the Air Force millions of dollars. CONCRETE APRON CASE The... aircraft using the pavement. The mean PCI for the feature was 70, which corresponded to a condition rating of "good." However, there was considerable

  10. Maintenance Operations Degradation of Airfield Pavement Markings

    DTIC Science & Technology

    2012-03-01

    the amount of light, which after emitted from a headlight is reflected from the pavement marker back to the driver (ASTM, 2005). Pavement markings...The geometry is based on the driver sitting 1.3 meters above the ground seeing the pavement marking 30 meters in front of the headlight . Figure 1...is the measure of how much light from a headlight reflects off of the marking and is directed back to the driver’s eye (ASTM 2005). Roadway

  11. Reduction of traffic and tire/pavement noise: 1st year results of the Arizona Quiet Pavement Program-Site III

    NASA Astrophysics Data System (ADS)

    Reyff, James A.; Donavan, Paul

    2005-09-01

    The Arizona Quiet Pavement Pilot Program overlaid major freeway segments in the Phoenix area with an Asphalt Rubber Friction Course (ARFC). The overlay was placed on various Portland Cement Concrete Pavement (PCCP) textures. Traffic noise reductions were evaluated by performing wayside traffic noise measurements and tire/pavement source level measurements. First year results for three different study sites are presented in this paper. Depending on the texture of the initial PCCP and microphone locations, reductions of up to 12 dBA in wayside traffic noise levels were measured. Similar reductions of tire/pavement source levels were measured. Results of the two methods are compared. Traffic conditions monitored during the measurements were modeled using the Federal Highway Administration's Traffic Noise Model (TNM 2.5) to compare modeled levels to those measured for PCCP and AFRC overlay conditions. The model under predicted levels for PCCP conditions and over predicted levels for AFRC conditions. The magnitude of under or over prediction varied with distance. The effect of propagation was examined and was aided by simultaneous measurements of wind conditions made by Arizona State University. TNM 2.5 was used to identify sound wall heights that were equivalent to the traffic noise reductions provided by the AFRC overlay.

  12. Repair and rehabilitation with polymer concrete

    SciTech Connect

    Kukacka, L.E.

    1988-09-01

    As a result of their fast setting characteristics and excellent mechanical and physical properties, polymer concretes (PC) are finding ever increasing useage for the repair of deteriorated portland cement concrete structures. Applications include the repair of highway pavements and bridge decks, airport runways, hydrotechnical structures, tunnels, and industrial flooring. The most commonly used resins and monomer systems for these applications are epoxies, polyesters and methylmethacrylate. Furfuryl alcohol has been used experimentally, and shows promise for use in making emergency repairs under adverse moisture or extreme temperature conditions. In the paper, repair procedures will be discussed and several case histories given. 6 refs.

  13. Effects of composition and exposure on the solar reflectance of Portland Cement Concrete

    SciTech Connect

    Levinson, Ronnen; Akbari, Hashem

    2002-06-01

    Increasing the solar reflectance (albedo) of a paved surface keeps it cooler in the sun, reducing convection of heat from pavement to air and thereby decreasing the ambient air temperature. Lower air temperatures decrease demand for cooling energy and slow the formation of urban smog. Variations with composition and environmental exposure of the albedos of portland cement concrete pavements were investigated through laboratory fabrication and exposure of 32 mixes of concrete. Concrete albedo generally correlated with cement albedo and sand albedo and, after abrasion, with rock albedo. Cement albedo had a disproportionately strong influence on the reflectance of concrete. Simulated weathering, soiling, and abrasion each reduced average concrete albedo, though some samples became slightly more reflective through weathering or soiling. Concrete albedo grew as the cement hydration reaction progressed, but stabilized within six weeks of casting.

  14. Time domain backcalculation of pavement

    NASA Astrophysics Data System (ADS)

    Matsui, Kunihito; Nishizawa, Tatsuo; Kikuta, Yukio

    1998-03-01

    Falling weight deflectometor (FWD) has been frequently used to evaluate structural integrity of pavement. The device applies an impulsive force on the surface of pavement and measure surface deflections at several locations including the place of loading. Although the test is dynamic, the data is regarded as pseudo-static data. According to common practice, using the peak load and the corresponding peak deflections, layer moduli are estimated in a static domain such that the measured peak deflections coincide with the corresponding calculated deflections based on the assumption of the theory of linear elasticity. This paper presents a method to back calculate layer moduli in dynamic domain such that the histories of both measured and calculated responses corresponding to the impulsive force coincide. Pavement is modeled by an axisymmetric linear elastic system. FEM is utilized coupled with Ritz vector to reduce a matrix and thus to improve computational efficiency. The backcalculation algorithm used is the Gauss-Newton method coupled with a truncated singular value decomposition.

  15. Improved Concrete Cutting and Excavation Capabilities for Crater Repair Phase 2

    DTIC Science & Technology

    2015-05-01

    Engineer Center to further improve the saw cutting and excavation production rates and robustness of crater repairs in thick portland cement concrete...18 in. or thicker) portland cement concrete (PCC) did not meet the required production rates for optimal efficiency and continuous work flow...excavation production rates and robustness of crater repairs in thick portland cement concrete (PCC) pavements for airfield damage repair (ADR

  16. A Knowledge-Base for Rehabilitation of Airfield Concrete Pavements

    DTIC Science & Technology

    1991-01-01

    30 2-11. FUEL FILTER RULE ..................................................... 32 2-12. CROSSWORD PUZZLE ARCHITECTURE...architecture. Lets assume a group of students in a classroom are going to solve a crossword puzzle that is drawn on a Blackboard. Although the clues to...German. Figure 2-12 shows how the crossword puzzle problem might be represented using a Blackboard architecture. The teacher will allow either the

  17. Asphalt Rubber Concrete Pavement. User’s Guide

    DTIC Science & Technology

    1994-09-01

    Wor6’ ’ Alexandria, VA 22310-3860 ’%cooir 1 ... for she An Mah~~ n , W &piný Aetmf Aumy &AM Destroy this report when no longer needed. Do not return it...IIOUI𔄀IM5Mo M NCY AMu(S) AID AIS(S) N P/•ONITORINGAGIN"Y REPORIT NUMBRI| U.S. Amy Cm " for Public Works FE.AP.UG-9412 7701 Telhiqi Road AlexAria VA...CODE " CAM• CLASRCI I _10SC]’- CLASFiCATIN t. SECURITY €IA$SIICATI) N 20. LIMITATION OF ABSTRACT OF oM TiF s PA41 OF ABSTRACT UicA1111_"-1- Uwcl

  18. Predicting pavement distress in oil field areas

    SciTech Connect

    Mason, J.M.; Scullion, T.; Stampley, B.E.

    1983-05-01

    A study on oil field traffic characteristics was performed and a procedure was developed for assessing current and future effects of oil field truck traffic on surface-treated (stage construction type) pavements. A computer program calculates several types of pavement distress and serviceability parameters to evaluate pavement performance under various axle load repetitions. Stepwise regression analysis of 132 surface-treated pavement sections led to the development of individual distress equations for rutting, raveling, flushing, alligator cracking, patching, longitudinal and transverse cracking, and failures (potholes). The versatility of the program provides a means of anticipating early pavement failures due to increased axle load repetitions. The program also provides the basic framework for computing the effects of other ''special-use'' truck traffic demands.

  19. Predicting pavement distress in oil field areas

    SciTech Connect

    Mason, J.M.; Scullion, T.; Stampley, B.E.

    1984-05-01

    A study on oil field traffic characteristics was performed and a procedure was developed for assessing current and future effects of oil field truck traffic on surface-treated (stage construction type) pavements. A computer program calculates several types of pavement distress and serviceability parameters to evaluate pavement performance under various axle load repetitions. Stepwise regression analysis of 132 surface-treated pavement sections led to the development of individual distress equations for rutting, raveling, flushing, alligator cracking, patching, longitudinal and transverse cracking, and failures (potholes). The versatility of the program provides a means of anticipating early pavement failures due to increased axle load repetitions. The program also provides the basic framework for computing the effects of other ''special-use'' truck traffic demands.

  20. Plastic (wire-combed) grooving of a slip-formed concrete runway overlay at Patrick Henry Airport: An initial evaluation

    NASA Technical Reports Server (NTRS)

    Marlin, E. C.; Horne, W. B.

    1977-01-01

    A wire-comb technique is described for transversely grooving the surface of a freshly laid (plastic state) slip-formed concrete overlay installed at Patrick Henry Airport. This method of surface texturing yields better water drainage and pavement skid resistance than that obtained with an older conventional burlap drag concrete surface treatment installed on an adjacent portion of the runway.

  1. Improving Rutting Resistance of Pavement Structures Using Geosynthetics: An Overview

    PubMed Central

    Karim, Mohamed Rehan; Khodaii, Ali; Almasi, Mohammad Hadi

    2014-01-01

    A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting). PMID:24526919

  2. Improving rutting resistance of pavement structures using geosynthetics: an overview.

    PubMed

    Mirzapour Mounes, Sina; Karim, Mohamed Rehan; Khodaii, Ali; Almasi, Mohammad Hadi

    2014-01-01

    A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting).

  3. INVESTIGATING PAVEMENT STRUCTURE DETERIORATION WITH A RELATIVE EVALUATION MODEL

    NASA Astrophysics Data System (ADS)

    Mori, Hisashi; Fujiwara, Eigo; Kaito, Kiyoyuki; Kobayashi, Kiyoshi; Hashimoto, Takumi

    The deterioration of pavement structure is a complex phenomenon that follows the deterioration of both pavement surface and pavement sub-surface. In addition, the deterioration progress of pavement sub-surface affects the deterioration speed of pavement surface. The road pavement management is important to determine the optimal repair strategy which considers the deterioration of both pavement surface and sub-surface (hereafter call "pavement structure"). This study proposes pavement repair planning and strategies of 1) extraction of key management section of relative evaluation based on road inspection survey results, and 2) determination of decision-making repair methodologies based on pavement structural soundness survey by FWD (Falling Weight Deflectometer) in key management sections. In addition, the National Highway Route 9 is the target area as empirical study to verify the methodology proposed in this study.

  4. Locating voids beneath pavement using pulsed electromagnetic waves

    NASA Astrophysics Data System (ADS)

    Steinway, W. J.; Echard, J. D.; Luke, C. M.

    1981-11-01

    The feasibility of using pulsed electromagnetic wave technology for locating and sizing voids beneath reinforced and nonreinforced portland cement concrete pavements is determined. The data processing techniques developed can be implemented to provide information for void depth and sizing to + or - 1/2 in. and spatial location within + or - 6 in. A very short pulse radar directly connected to a microcomputer was chosen as the equipment necessary to obtain measurements. This equipment has the required accuracy and reliability, and is a cost effective solution for the void locating problem. The radar provides a signal return from voids that has unique characteristics that can be examined to provide information regarding the location, depth, and shape of the void. The microcomputer provides a means of real time processing to extract the information from the radar signal return and record the results. Theoretical modeling of signal returns from voids led to suitable techniques for locating and sizing voids beneath the pavement. Analysis and application of these techniques to radar measurements verified the theoretical predictions that radar can be used to determine the location, size, and shape of actual voids.

  5. Evaluation of bridge decks and pavements at highway speed using ground-penetrating radar

    NASA Astrophysics Data System (ADS)

    Maser, Kenneth R.

    1995-05-01

    Ground penetrating radar has been developed as an economical alternative for evaluating pavement layer properties and estimating quantities of deterioration in bridge decks. These highway applications are based on the use of vehicle-mounted radar systems traveling at normal driving speed. Surveys are conducted without lane closures, and extensive coverage can be obtained in a short survey period. Customized software has been specifically developed to handle and interpret the large quantities of data collected by this system. Two integrated software systems have been developed and extensively tested for pavement layer thickness and bridge deck condition evaluation. PAVLAYER, for pavements, has demonstrated an accuracy of +/- 7% for asphalt layer thickness evaluation based on tests on 150 pavement sections and correlation with over 700 cores. DECAR, for evaluating quantities of deteriorated concrete in bridge decks, has demonstrated an accuracy of +/- 4.4% of the total deck area based on ground truth evaluation of 64 bridge decks. The paper describes the details of the hardware and software components and the analytic methods used in these two systems. Also presented are descriptions of three field evaluation programs, in which the PAVLAYER and DECAR results are correlated with ground truth. Typical output and ground truth correlations are presented.

  6. Assessment of the performance of rigid pavement back-calculation through finite element modeling

    NASA Astrophysics Data System (ADS)

    Shoukry, Samir N.; William, Gergis W.; Martinelli, David R.

    1999-02-01

    This study focuses on examining the behavior of rigid pavement layers during the Falling Weight Deflectometer (FWD) test. Factors affecting the design of a concrete slab, such as whether the joints are doweled or undoweled and the spacing between the transverse joints, were considered in this study. Explicit finite element analysis was employed to investigate pavement layers' responses to the action of the impulse of the FWD test. Models of various dimensions were developed to satisfy the factors under consideration. The accuracy of the finite element models developed in this investigation was verified by comparing the finite element- generated deflection basin with that experimentally measured during an actual test. The results showed that the measured deflection basin can be reproduced through finite element modeling of the pavement structure. The resulting deflection basins from the use FE modeling was processed in order to backcalculate pavement layer moduli. This approach provides a method for the evaluation of the performance of existing backcalculation programs which are based on static elastic layer analysis. Based upon the previous studies conducted for the selection of software, three different backcalculation programs were chosen for the evaluation: MODULUS5.0, EVERCALC4.0, and MODCOMP3. The results indicate that ignoring the dynamic nature of the load may lead to crude results, especially during backcalculation procedures.

  7. Pavement crack characteristic detection based on sparse representation

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoming; Huang, Jianping; Liu, Wanyu; Xu, Mantao

    2012-12-01

    Pavement crack detection plays an important role in pavement maintaining and management. The three-dimensional (3D) pavement crack detection technique based on laser is a recent trend due to its ability of discriminating dark areas, which are not caused by pavement distress such as tire marks, oil spills and shadows. In the field of 3D pavement crack detection, the most important thing is the accurate extraction of cracks in individual pavement profile without destroying pavement profile. So after analyzing the pavement profile signal characteristics and the changeability of pavement crack characteristics, a new method based on the sparse representation is developed to decompose pavement profile signal into a summation of the mainly pavement profile and cracks. Based on the characteristics of the pavement profile signal and crack, the mixed dictionary is constructed with an over-complete exponential function and an over-complete trapezoidal membership function, and the signal is separated by learning in this mixed dictionary with a matching pursuit algorithm. Some experiments were conducted and promising results were obtained, showing that we can detect the pavement crack efficiently and achieve a good separation of crack from pavement profile without destroying pavement profile.

  8. Water quality and quantity assessment of pervious pavements performance in experimental car park areas.

    PubMed

    Sañudo-Fontaneda, Luis A; Charlesworth, Susanne M; Castro-Fresno, Daniel; Andres-Valeri, Valerio C A; Rodriguez-Hernandez, Jorge

    2014-01-01

    Pervious pavements have become one of the most used sustainable urban drainage system (SUDS) techniques in car parks. This research paper presents the results of monitoring water quality from several experimental car park areas designed and constructed in Spain with bays made of interlocking concrete block pavement, porous asphalt, polymer-modified porous concrete and reinforced grass with plastic and concrete cells. Moreover, two different sub-base materials were used (limestone aggregates and basic oxygen furnace slag). This study therefore encompasses the majority of the materials used as permeable surfaces and sub-base layers all over the world. Effluent from the test bays was monitored for dissolved oxygen, pH, electric conductivity, total suspended solids, turbidity and total petroleum hydrocarbons in order to analyze the behaviour shown by each combination of surface and sub-base materials. In addition, permeability tests were undertaken in all car parks using the 'Laboratorio Caminos Santander' permeameter and the Cantabrian Portable Infiltrometer. All results are presented together with the influence of surface and sub-base materials on water quality indicators using bivariate correlation statistical analysis at a confidence level of 95%. The polymer-modified porous concrete surface course in combination with limestone aggregate sub-base presented the best performance.

  9. Plains Traveler

    NASA Image and Video Library

    2006-04-10

    This MOC image shows a dust devil traveling across a plain west-southwest of Schiaparelli Crater, in far eastern Sinus Meridiani. The dust devil is casting a shadow toward the northeast, just south below of an egg-shaped crater

  10. Nondestructive Handheld Fourier Transform Infrared (FT-IR) Analysis of Spectroscopic Changes and Multivariate Modeling of Thermally Degraded Plain Portland Cement Concrete and its Slag and Fly Ash-Based Analogs.

    PubMed

    Leung Tang, Pik; Alqassim, Mohammad; Nic Daéid, Niamh; Berlouis, Leonard; Seelenbinder, John

    2016-05-01

    Concrete is by far the world's most common construction material. Modern concrete is a mixture of industrial pozzolanic cement formulations and aggregate fillers. The former acts as the glue or binder in the final inorganic composite; however, when exposed to a fire the degree of concrete damage is often difficult to evaluate nondestructively. Fourier transform infrared (FT-IR) spectroscopy through techniques such as transmission, attenuated total reflectance, and diffuse reflectance have been rarely used to evaluate thermally damaged concrete. In this paper, we report on a study assessing the thermal damage of concrete via the use of a nondestructive handheld FT-IR with a diffuse reflectance sample interface. In situ measurements can be made on actual damaged areas, without the need for sample preparation. Separate multivariate models were developed to determine the equivalent maximal temperature endured for three common industrial concrete formulations. The concrete mixtures were successfully modeled displaying high predictive power as well as good specificity. This has potential uses in forensic investigation and remediation services particularly for fires in buildings.

  11. Temporal evolution modeling of hydraulic and water quality performance of permeable pavements

    NASA Astrophysics Data System (ADS)

    Huang, Jian; He, Jianxun; Valeo, Caterina; Chu, Angus

    2016-02-01

    A mathematical model for predicting hydraulic and water quality performance in both the short- and long-term is proposed based on field measurements for three types of permeable pavements: porous asphalt (PA), porous concrete (PC), and permeable inter-locking concrete pavers (PICP). The model was applied to three field-scale test sites in Calgary, Alberta, Canada. The model performance was assessed in terms of hydraulic parameters including time to peak, peak flow and water balance and a water quality variable (the removal rate of total suspended solids). A total of 20 simulated storm events were used for model calibration and verification processes. The proposed model can simulate the outflow hydrographs with a coefficient of determination (R2) ranging from 0.762 to 0.907, and normalized root-mean-square deviation (NRMSD) ranging from 13.78% to 17.83%. Comparison of the time to peak flow, peak flow, runoff volume and TSS removal rates between the measured and modeled values in model verification phase had a maximum difference of 11%. The results demonstrate that the proposed model is capable of capturing the temporal dynamics of the pavement performance. Therefore, the model has great potential as a practical modeling tool for permeable pavement design and performance assessment.

  12. Possibilities of ground penetrating radar usage within acceptance tests of rigid pavements

    NASA Astrophysics Data System (ADS)

    Stryk, Josef; Matula, Radek; Pospisil, Karel

    2013-10-01

    Within the road pavement acceptance tests, destructive as well as non-destructive tests of individual road layers are performed to verify the standard requirements. The article describes a method for providing quick, effective and sufficiently accurate measurements of both dowel and tie bar positions in concrete pavements, using a two-channel ground penetrating radar (GPR). Measurements were carried out in laboratory and in-situ conditions. A special hand cart for field measurements, set for the testing requirements, was designed. It was verified that following the correct measuring and assessment method, it is possible to reach accuracy of determining the in-built rebar up to 1 cm in vertical direction and up to 1.5 cm per 11.5 m of measured length in horizontal direction. In the in-situ tests, GPR identification of possible anomalies due to the phase of concrete pavement laying was presented. In the conclusion, a measurement report is mentioned. The standard requirements for the position of dowels and tie bars cover maximum possible deviation of the rebar position from the project documentation in vertical and horizontal direction, maximum deflection of rebar ends to each other, and maximum translation of rebar in the direction of its longitudinal axis.

  13. Diagnosis of moisture damage in asphalt pavements

    NASA Astrophysics Data System (ADS)

    Canning, Jacqueline S.; Niezrecki, Christopher; Birgisson, Bjorn

    2004-07-01

    One of the most common modes of premature failure of asphalt pavements is water damage. Moisture damage in hot-mix asphalt (HMA) pavements occurs when water infiltrates the pavement system, causing premature failure of hot-mix asphalt pavements, primarily through loss of adhesion between the asphalt binder and the aggregates. Loss of adhesion can lead to stripping of the asphalt film from the aggregate and raveling, where aggregates are dislodged from the pavement. The laboratory testing procedures currently available for testing HMA moisture susceptibility were primarily developed to determine the degree of resistance to moisture damage by a particular combination of asphalt and aggregate as well as compare mixes composed of different types and quantities of aggregate. These methods are all based on destructive testing. There is currently a need for innovative nondestructive testing technologies that can be used to identify and isolate the effects of water damage in mixtures. As a first step in the development of a non-destructive method to test HMA pavements, modal hammer tests were conducted on several test specimens of fine and coarse grained granite-based mixes commonly used by the Florida Department of Transportation (FDOT). The results of the testing indicate that there is a large frequency shift in the transfer function measurements for the damaged samples compared to the undamaged samples. The results imply that modal hammer testing may be used as a method to characterize the health of HMA pavements.

  14. Effective flow resistivity of highway pavements.

    PubMed

    Rochat, Judith L; Read, David R

    2013-12-01

    In the case of highway traffic noise, propagating sound is influenced by the ground over which it travels, whether it is the pavement itself or the ground between the highway and nearby communities. Properly accounting for ground type in modeling can increase accuracy in noise impact determinations and noise abatement design. Pavement-specific effective flow resistivity values are being investigated for inclusion in the Federal Highway Administration Traffic Noise Model, which uses these values in the sound propagation algorithms and currently applies a single effective flow resistivity value to all pavement. Pavement-specific effective flow resistivity values were obtained by applying a modified version of the American National Standards Institute S1.18 standard. The data analysis process was tailored to allow for increased sensitivity and extraction of effective flow resistivity values for a broad range of pavements (sound absorptive to reflective). For porous pavements (sound absorptive), it was determined that examination of the measured data can reveal influence from an underlying structure. Use of such techniques can aid in the design of quieter pavements.

  15. Pavement Evaluation Concepts Using Nondestructive Structural Evaluation and Pavement Condition Index.

    DTIC Science & Technology

    1987-04-01

    FILE COPY P~MISCELLANEOUS PAPER GL-87-5 PAVEMENT EVALUATION CONCEPTS USING * i NONDESTRUCTIVE STRUCTURAL EVALUATION AND PAVEMENT CONDITION INDEX by...Nondestructive Structural Evaluation and Pavement Condition Index 12, PERSONAL AUTHOR(S) Hall, Jim W., Jr. 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF... index and results of nondestructive testing structural evaluation. A flowchart outlining the decision process of identifyinp appropriate alternatives

  16. Assessment of highway pavements using GPR

    NASA Astrophysics Data System (ADS)

    Plati, Christina; Loizos, Andreas

    2015-04-01

    Highway infrastructure is a prerequisite for a functioning economy and social life. Highways, often prone to congestion and disruption, are one of the aspects of a modern transport network that require maximum efficiency if an integrated transport network, and sustainable mobility, is to be achieved. Assessing the condition of highway structures, to plan subsequent maintenance, is essential to allow the long-term functioning of a road network. Optimizing the methods used for such assessment will lead to better information being obtained about the road and underlying ground conditions. The condition of highway structures will be affected by a number of factors, including the properties of the highway pavement, the supporting sub-base and the subgrade (natural ground), and the ability to obtain good information about the entire road structure, from pavement to subgrade, allows appropriate maintenance programs to be planned. The maintenance of highway pavements causes considerable cost and in many cases obstruction to traffic flow. In this situation, methods that provide information on the present condition of pavement structure non-destructively and economically are of great interest. It has been shown that Ground-Penetrating-Radar (GPR), which is a Non Destructive Technique (NDT), can deliver information that is useful for the planning of pavement maintenance activities. More specifically GPR is used by pavement engineers in order to determine physical properties and characteristics of the pavement structure, information that is valuable for the assessment of pavement condition. This work gives an overview on the practical application of GPR using examples from highway asphalt pavements monitoring. The presented individual applications of GPR pavement diagnostics concern structure homogeneity, thickness of pavement layers, dielectric properties of asphalt materials etc. It is worthwhile mentioning that a number of applications are standard procedures, either

  17. Substandard Materials for Pavement Construction

    DTIC Science & Technology

    1988-09-01

    Oceanlake basalt is a high quality aggregate, and the other basalt is subject to severe degradation in the pres- ence of water. The Tysee sandstone is a...15 percent is common for paving quality concrete) the Oceanlake basalt could reach modulus values (4 to 6 million lb/in. 2)* and tensile strength (600...700 lb/in. 2) expected of good quality paving concrete. The Eckman Creek basalt had an identical gradation to the Oceanlake basalt but had appreciably

  18. Nature based solutions to mitigate soil sealing in urban areas: Results from a 4-year study comparing permeable, porous, and impermeable pavements.

    PubMed

    Fini, A; Frangi, P; Mori, J; Donzelli, D; Ferrini, F

    2017-07-01

    Soil sealing is one of the most pervasive forms of soil degradation that follows urbanization and, despite innovative pavements (i.e. pervious) are being installed in urban areas to mitigate it, there is little research on the effects of pervious pavements on soil water and carbon cycle and on the physiology of urban trees. The aim of this 4-year experiment was to assess the effects of three pavements, differing in permeability to water and gases, on some soil physical parameters, and on growth and physiology of newly planted Celtis australis and Fraxinus ornus. Treatments were: 1) impermeable pavement (asphalt on concrete sub-base); 2) permeable pavement (pavers on crushed rock sub-base); 3) porous design (porous pavement on crushed rock sub-base); 4) control (unpaved soil, kept free of weed by chemical control). Soil (temperature, moisture, oxygen content and CO2 efflux) and plant (above- and below-ground growth, leaf gas exchange, chlorophyll fluorescence, water relations) parameters were measured. All types of pavements altered the water cycle compared to unpaved soil plots, but this disturbance was less intense in porous pavements than in other soil cover types. Porous pavements allowed both higher infiltration and evaporation of water than both pavers and asphalt. Reduction of evaporative cooling from soil paved with permeable and impermeable pavements contributed to significant soil warming: at 20cm depth, soils under concrete pavers and asphalt were 4 and 5°C warmer than soil covered by porous pavements and unpaved soils, respectively. Thus, enhancing evaporation from paved soil by the use of porous pavements may contribute to mitigating urban heat islands. CO2 greatly accumulated under impermeable and permeable pavements, but not under porous pavements, which showed CO2 efflux rates similar to control. Soil oxygen slightly decreased only beneath asphalt. Growth of newly planted C. australis and F. ornus was little affected by pavement type. Tree

  19. Cathodic protection of steel reinforced concrete facilitated by using carbon fiber reinforced mortar or concrete

    SciTech Connect

    Hou, J.; Chung, D.D.L.

    1997-05-01

    Due to the decrease in volume electrical resistivity associated with carbon fiber addition (0.35 vol.%) to concrete (embedding steel rebar), concrete containing carbon fibers and silica fume reduced by 18% the driving voltage required for cathodic protection compared to plain concrete, and by 28% compared to concrete with silica fume. Due to the decrease in resistivity associated with carbon fiber addition (1.1 vol.%) to mortar, overlay (embedding titanium wires for electrical contacts to steel reinforced concrete) in the form of mortar containing carbon fibers and latex reduced by the 10% the driving voltage required for cathodic protection, compared to plain mortar overlay. In spite of the low resistivity of mortar overlay with carbon fibers, cathodic protection required multiple metal electrical contacts embedded in the mortar at a spacing of 11 cm or less.

  20. Characterizing a porous road pavement using surface impedance measurement: a guided numerical inversion procedure.

    PubMed

    Benoit, Gaëlle; Heinkélé, Christophe; Gourdon, Emmanuel

    2013-12-01

    This paper deals with a numerical procedure to identify the acoustical parameters of road pavement from surface impedance measurements. This procedure comprises three steps. First, a suitable equivalent fluid model for the acoustical properties porous media is chosen, the variation ranges for the model parameters are set, and a sensitivity analysis for this model is performed. Second, this model is used in the parameter inversion process, which is performed with simulated annealing in a selected frequency range. Third, the sensitivity analysis and inversion process are repeated to estimate each parameter in turn. This approach is tested on data obtained for porous bituminous concrete and using the Zwikker and Kosten equivalent fluid model. This work provides a good foundation for the development of non-destructive in situ methods for the acoustical characterization of road pavements.

  1. The Edison Environmental Center Permeable Pavement Site

    EPA Science Inventory

    This a presentation for a Community Outreach Event called "Chemistry Works and Celebration of International Year of Chemistry." It will review the permeable pavement research project at the Edison Environmental center.

  2. The Edison Environmental Center Permeable Pavement Site

    EPA Science Inventory

    This a presentation for a Community Outreach Event called "Chemistry Works and Celebration of International Year of Chemistry." It will review the permeable pavement research project at the Edison Environmental center.

  3. Mobile acoustic system for the detection of surface-breaking cracks in pavement

    NASA Astrophysics Data System (ADS)

    Marzani, Alessandro; Rizzo, Piervincenzo; Lanza di Scalea, Francesco; Benzoni, Gianmario

    2004-07-01

    Monitoring the structural condition of road and airport pavement is an extremely critical task to ensure the safety and efficiency of teh transportation. The topic is relevant to both civil and military transportation infrastructure. The presence of damage in pavement, including surface cracking, depressions, swells, and wear, is inevitable due to the sever environmental and service loads that these structures must be subject to. Existing NDE techniques aimed at assessing the structural condition of pavement include Falling Weight Deflectometer, Ground Penetrating Radar, and acoustic methods based on surface waves. This paper presents improvements to the traditional surface-wave method for the detection of surface-breaking cracks in pavement. The advances include 1) the modeling of the problem as dipsersive waves propagating in a multilayer system, 2) the inclusion of post-processing algorithms based on the Wavelet Transform to improve the sensitivity and accuracy of the inspection, and 3) the use of non-contact, air-coupled acoustic detectors to enhance the mobility of the inspection unit. The crack detection procedure consists of first generating a dispersive wave with an impulse hammer, and then measuring the changes in velocity, amplitude and/or frequency content as the wave travels across the flaw with the aid of the Continuous Wavelet Transform. Multilayer wave propagation modeling provides a better understanding of the experimental results by predicting how the various frequencies interact with cracks of different depths. The results of field tests will be presented for both rigid (concrete-based) and flexible (bitumen-based) pavement with surface cracks.

  4. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement

    USGS Publications Warehouse

    Van Metre, Peter C.; Majewski, Michael S.; Mahler, Barbara J.; Foreman, William T.; Braun, Christopher L.; Wilson, Jennifer T.; Burbank, Teresa L.

    2012-01-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the pavement surface of seven sealed (six with coal-tar-based sealant and one with asphalt-based sealant) and three unsealed (two asphalt and one concrete) parking lots in central Texas. PAHs also were measured in parking lot dust. The geometric mean concentration of the sum of eight frequently detected PAHs (ΣPAH8) in the 0.03-m samples above sealed lots (1320 ng m-3) during the hottest part of the day was 20 times greater than that above unsealed lots (66.5 ng m-3). The geometric mean concentration in the 1.28-m samples above sealed lots (138 ng m-3) was five times greater than above unsealed lots (26.0 ng m-3). Estimated PAH flux from the sealed lots was 60 times greater than that from unsealed lots (geometric means of 88 and 1.4 μg m-2 h-1, respectively). Although the data set presented here is small, the much higher estimated fluxes from sealed pavement than from unsealed pavement indicate that coal-tar-based sealants are emitting PAHs to urban air at high rates compared to other paved surfaces.

  5. Pavement-marking materials: New York's experience

    NASA Astrophysics Data System (ADS)

    Bryden, J. E.; Gurney, G. F.

    1984-04-01

    A wide range of stripping materials is available for pavement-marking programs. The four basic systems; traffic paint, thermoplastic, preformed tape, and field-reacted materials are described, as well as the various materials used in each system, including cost, durability, methods of installation and mantenance, visibility, and handling safety. New York State's pavement marking policies are described. Information on stripping costs, material usage, and results of durability studies is provided, based on New York's experience with most currently available marking materials.

  6. Backcalculation of Composite Pavement Layer Moduli

    DTIC Science & Technology

    1990-09-01

    pavement system. Figure 1 illustrates some of the differences between a typical idealized model and a real pavement system. In general, the properties of...the real and idealized systems are not the same. Use of nondestructive test data to backcalculate layer properties implies that equivalent deflection...assumed idealized model. If layer properties from the idealized model are to be used in a 5 subsequent overlay design or remaining life prediction, it

  7. Open-Graded Bases for Airfield Pavements.

    DTIC Science & Technology

    1987-07-01

    pressure. 7. The rapid drainage of the bases is particularly important for rigid pavement to prevent pumping at the joints. Cedergren (1974) was a particu...filter cloth, collector trenches or perforated collector pipe, pipe outlets, and outlet markers. 11. From the studies by Cedergren , Rollings, and...paper No. 2516, American Society of Civil Engineers, New York. Cedergren , H. R. 1974a. Drainage of Highway and Airfield Pavements, John Wiley and Sons

  8. Recycled Materials - Applications to Air Force Pavements.

    DTIC Science & Technology

    1980-09-01

    an unlimited supply of natural materials. Since the embargo, the law of supply and demand had pushed the price of asphalt to $180 per ton* by early...are a number of reasons for planing the pae,.-%nt surface ( Lawing , 1976). The pavement surface over a bridge can be re- moved by planing before...Donald :. 979. "Recyc.in, Aschalt Pavements," Federal Highway Admistration Demonstration roject N-. 39, Sherburne, Vt., 38 pp. Ga-nnon, Charles R., et

  9. Consequence of Layer Separation on Pavement Performance.

    DTIC Science & Technology

    1987-04-01

    computer program BISAR ( Bitumen Structures Analy- sis in Roads)4 was used. This program uses elastic layer theory to analyze multilayered systems subjected...horizontal strains in the pavement section directly under one DC-9 wheel for both frictionless slippage and full adhesion between the pavement layers. With no...December 1978). "BISAR ( Bitumen Structures Analysis in Roads), Computer program, User’s Manual (Abbreviated Version) (Koninklijke/Shell-Laboratorium

  10. Fracture of highway and airport pavements

    NASA Astrophysics Data System (ADS)

    Ramsamooj, D. V.

    1993-03-01

    Existing solutions for the stresses in a cracked slab containing a crack and supported by an elastic foundation are extended to obtain the stress intensity factor (SIF) for a crack in a pavement subjected to moving vehicular loads. In the existing solutions the stresses can be obtained only for a uniform bending stress (before the crack occurs) along the crack surface. For pavements subjected to moving vehicular loads, the stress distribution along the crack surface is not uniform and the approximation of a uniform stress is often unsatisfactory. The present work extends the above solutions to cover more realistic loading of highway and airport pavements. This facilitates the application of the principles of fracture mechanics to the fatigue crack propagation and fracture of pavements. Beginning with a part-through semi-elliptical starter crack, the crack is assumed to grow under load and the SIF is presented at various stages of crack growth, from the starter crack into a short through-crack that eventually becomes a very long through-crack. Some examples of the fracture of typical rigid and flexible highway and airport pavements are presented to show the need to consider fracture in the design of pavements.

  11. Fusing complementary images for pavement cracking measurements

    NASA Astrophysics Data System (ADS)

    Yao, Ming; Zhao, Zuyun; Yao, Xun; Xu, Bugao

    2015-02-01

    Cracking is a major pavement distress that jeopardizes road serviceability and traffic safety. Automated pavement distress survey (APDS) systems have been developed using digital imaging technology to replace human surveys for more timely and accurate inspections. Most APDS systems require special lighting devices to illuminate pavements and prevent shadows of roadside objects that distort cracks in the image. Most artificial lighting devices are laser based, and are either hazardous to unprotected people or require dedicated power supplies on the vehicle. This study was aimed to develop a new imaging system that can scan pavement surface at highway speed and determine the level of severity of pavement cracking without using any artificial lighting. The new system consists of dual line-scan cameras that are installed side by side to scan the same pavement area as the vehicle moves. Cameras are controlled with different exposure settings so that both sunlit and shadowed areas can be visible in two separate images. The paired images contain complementary details useful for reconstructing an image in which the shadows are eliminated. This paper intends to present (1) the design of the dual line-scan camera system, (2) a new calibration method for line-scan cameras to rectify and register paired images, (3) a customized image-fusion algorithm that merges the multi-exposure images into one shadow-free image for crack detection, and (4) the results of the field tests on a selected road over a long period.

  12. Aircraft-Pavement Compatibility Study

    DTIC Science & Technology

    1974-09-01

    Hn -. lit" PCC EAA-Clti I960 12 E-7 Rc lit" PCC FAA-Cit-y 1961 6A E-7 RO -. - 1’t" PCC ## CAA-Cltj 1*7 7A E-7 RC • _ lit" PCC ♦* CAA- Cita 1959...line 190- 8 IRPORT PAVEMENT CHARACTERISTICS Table A2 (Continued) ]1 ’m, »73 OESION ALLOW. CONtTRUC »IC VEAR WFA- cita CAA-Clta~19U3 CM...8217 CA 7" Bit. T’ AC 51 apa 14 + 1»"AC 197^ R-2 El/fii Fa/Fl IV’CA 7" Bit. S Ac ^222. m FaTn ^n us: RX" MM 10" CA 7" Bit. 3" AC ?^7^ B=5_ R-6

  13. Reinforced Concrete on Constitutive Relations

    DTIC Science & Technology

    1975-02-01

    elements, it can also be applied to homo - geneous elements of plain concrete or rock, etc., by eliminating from the analysis the terms...etc«» »■’)« «»(•BONDING kyrf.9 CRACX ECCao.Ol’fcC ir (ros.u.rt.) Ecc »E»eo^o*Ec KFTURM END KFH 1 HtU 2 Rtb ) RtH 4 HEB 5 REB 6 299

  14. Plains Traveler

    NASA Technical Reports Server (NTRS)

    2006-01-01

    10 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dust devil traveling across a plain west-southwest of Schiaparelli Crater, in far eastern Sinus Meridiani. The dust devil is casting a shadow toward the northeast, just south (below) of an egg-shaped crater.

    Location near: 6.4oS, 349.3oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

  15. Utopia Plain

    NASA Technical Reports Server (NTRS)

    2006-01-01

    5 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dark-toned, cratered plain in southwest Utopia Planitia. Large, light-toned, windblown ripples reside on the floors of many of the depressions in the scene, including a long, linear, trough.

    Location near: 30.3oN, 255.3oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  16. Plains Traveler

    NASA Technical Reports Server (NTRS)

    2006-01-01

    10 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dust devil traveling across a plain west-southwest of Schiaparelli Crater, in far eastern Sinus Meridiani. The dust devil is casting a shadow toward the northeast, just south (below) of an egg-shaped crater.

    Location near: 6.4oS, 349.3oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

  17. Mechanical properties of concrete containing a high volume of tire-rubber particles.

    PubMed

    Khaloo, Ali R; Dehestani, M; Rahmatabadi, P

    2008-12-01

    Due to the increasingly serious environmental problems presented by waste tires, the feasibility of using elastic and flexible tire-rubber particles as aggregate in concrete is investigated in this study. Tire-rubber particles composed of tire chips, crumb rubber, and a combination of tire chips and crumb rubber, were used to replace mineral aggregates in concrete. These particles were used to replace 12.5%, 25%, 37.5%, and 50% of the total mineral aggregate's volume in concrete. Cylindrical shape concrete specimens 15 cm in diameter and 30 cm in height were fabricated and cured. The fresh rubberized concrete exhibited lower unit weight and acceptable workability compared to plain concrete. The results of a uniaxial compressive strain control test conducted on hardened concrete specimens indicate large reductions in the strength and tangential modulus of elasticity. A significant decrease in the brittle behavior of concrete with increasing rubber content is also demonstrated using nonlinearity indices. The maximum toughness index, indicating the post failure strength of concrete, occurs in concretes with 25% rubber content. Unlike plain concrete, the failure state in rubberized concrete occurs gently and uniformly, and does not cause any separation in the specimen. Crack width and its propagation velocity in rubberized concrete are lower than those of plain concrete. Ultrasonic analysis reveals large reductions in the ultrasonic modulus and high sound absorption for tire-rubber concrete.

  18. Rigid and Flexible Pavement Aircraft Tie-Downs

    DTIC Science & Technology

    2010-05-01

    AFRL-RX-TY-TR-2010-0093 RIGID AND FLEXIBLE PAVEMENT AIRCRAFT TIE-DOWNS Christopher Jackson and Athar Saeed Applied Research Associates...MAR-2010 Rigid and Flexible Pavement Aircraft Tie-Downs FA4819-09-C-0028 62102F 4915 D1 4915D14E *Jackson, Christopher J.; *Saeed, Athar; **Lackey...tie-downs, although additional testing is necessary before recommending this option. rigid pavement aircraft tie-downs, flexible pavement aircraft

  19. Evaluation of Procedures for Backcalculation of Airfield Pavement Moduli

    DTIC Science & Technology

    2015-08-01

    9  2.1.6  Pavement core drill ................................................................................................... 10  2.2...PSPA equipment and laptop. 2.1.6 Pavement core drill A pavement core drill is used to provide supplementary data to that collected with the HWD...splitting tensile test. Six-in.-diam cores are generally used by the USAF for both PCC and AC pavements, and the core drills are capable of coring to

  20. Development of Predictive Equations Based on Pavement Condition Index Data

    DTIC Science & Technology

    1992-03-01

    solutions to eliminate existing problems. A Spavement management system not only evaluates the present condition of a pavement but predicts its future...structural performance [1]. Condition rating data collected periodically will track the performance of a pavement. Most airports presently utilize...three primary objectives of rating a pavement based on the PCI method: (1) Determine present condition of the pavement in terms of the apparent

  1. Airfield Pavement Evaluation: Pisco and La Joya Air Bases, Peru

    DTIC Science & Technology

    1989-11-01

    ORCEBAE KFLORIDA 󈧜 03 -6 001 AIRFIELD PAVEMENT EVALUATION OF PERUVIAN AIR BASES PREPARED FOR TACTICAL AIR COMMAND (TAC) BY HQ AFESC PAVEMENT... AIR FORCE ENGINEERING AND SERVICES CENTER TYNDALL AIR FORCE BASE FLORIDA 32403-6001 PUBLISHED NOVEMBER 1989 A pwrvsd hE’ pubgecIa. TABLE OF CONTENTS... Air Command, a Pavement Evaluation Team from HQ Air Force Engineering and Services Center (AFESC) performed modified destructive airfield pavement

  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. Example of using small falling weight deflectomer (FWD) for Earth structures and low cost road pavement in Japan

    NASA Astrophysics Data System (ADS)

    Shibata, Hideaki; Tanaka, Yasutomo; Ono, Isamu; Okano, Tsuyoshi

    2007-01-01

    The FWD (Falling Weight Deflectometer) is an instrument which makes the weight fall freely on its loading plate to apply impact load and measures the displacement caused by the fall at the center of impact load and also at the points in radial direction from the center of impact load. A kind of instrument which is mounted on or drawn by a vehicle used for construction of concrete pavement or asphalt pavement of a runway is usually called FWD. The impact load of FWD is 49KN to 196kN and it can obtain the modulus of elasticity of each pavement layer by back analysis based on the theory of multi-layer elasticity using 6 to 8 of extemal displacement sensors. On the other hand, the small FWD is an FWD which is constructed small and easy and is applicable for hand carry. It makes the weight fall freely on the loading plate to apply impact load and measures the load and displacement caused by the fall. It was developed for mainly assessing the rigidity and bearing capacity of the subgrade easily and promptly. It can measure many points in short term and obtain coefficient of subgrade reaction and modulus of subgrade elasticity without using reaction facilities like as plate bearing test or CBR test. It has also been tried to apply the small FWD to low cost asphalt road pavement (later called as low cost road pavement). Application examples of small FWD test for earth structure and low cost load pavement in Japan are shown and the methods and test results are stated in this report.

  4. 19. Virginia Route 605 grade separation structure. This reinforced concrete ...

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

    19. Virginia Route 605 grade separation structure. This reinforced concrete rigid frame structure. This reinforced concrete rigid frame structure was built in 1950. It is an example of the most common ornament used on the parkway where the headwall, wingwalls, and railing is faced rusticated stone, but not the interior abutment walls and the bottom of the arch are plain concrete. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  5. Pavement Sealcoat, PAHs, and the Environment

    NASA Astrophysics Data System (ADS)

    Van Metre, P. C.; Mahler, B. J.

    2011-12-01

    Recent research by the USGS has identified coal-tar-based pavement sealants as a major source of polycyclic aromatic hydrocarbons (PAHs) to the environment. Coal-tar-based sealcoat is commonly used to coat parking lots and driveways and is typically is 20-35 percent coal tar pitch, a known human carcinogen. Several PAHs are suspected mutagens, carcinogens, and (or) teratogens. In the central and eastern U.S. where the coal-tar-based sealants dominate use, sum-PAH concentration in dust particles from sealcoated pavement is about 1,000 times higher than in the western U.S. where the asphalt-based formulation is prevalent. Source apportionment modeling indicates that particles from sealcoated pavement are contributing the majority of the PAHs to recent lake sediment in 35 U.S. urban lakes and are the primary cause of upward trends in PAHs in many of these lakes. Mobile particles from parking lots with coal-tar-based sealcoat are tracked indoors, resulting in elevated PAH concentrations in house dust. In a recently completed study, volatilization fluxes of PAHs from sealcoated pavement were estimated to be about 60 times fluxes from unsealed pavement. Using a wide variety of methods, the author and colleagues have shown that coal-tar-based sealcoat is a major source of PAHs to the urban environment and might pose risks to aquatic life and human health.

  6. ACAA pavement manual. Recommended practice: Coal fly ash in pozzolanic stabilized mixtures for flexible pavement systems

    SciTech Connect

    Not Available

    1991-01-01

    The purpose of this manual is to guide pavement design engineers, materials engineers, and construction managers in the design and construction of flexible pavement systems in which low- to high-strength Pozzolanic Stabilized Mixtures' ( PSMs') serve as base layers. A PSM incorporates coal fly ash in combination with activators, aggregates and water. Each of three design methods is useful for determining the thickness of a PSM base layer for a flexible pavement system: Method A - American Association of State Highway and Transportation Officials (AASHTO) flexible pavement design procedures, using structural layer coefficients; Method B - Mechanistic pavement design procedures, using resilient modulus values for the pavement layers; and Method C - A combination of Method A and Method B, using mechanistic design concepts for determining pavement layer coefficients. PSMs offer several advantages: PSMs are strong, durable mixtures using locally available materials; PSMs are economically competitive with properly engineered full-depth asphalt or crushed stone base courses; PSMs are suited to stabilizing recycled base mixtures; and PSMs are placed and compacted with conventional construction equipment. To provide the needed guidance for capturing the long-term service and cost-saving features of a PSM design, this manual details the following: a procedure for proportioning PSMs; thickness design procedures which include base layer and asphalt wearing course; and proven techniques for PSM mixing and base layer construction.

  7. A fiber-reinforced composite structure for the repair of thermally cracked bituminous pavements

    NASA Astrophysics Data System (ADS)

    Frantzen, Jeffrey Alan

    1998-10-01

    The apparatus under development in this project is a structural component or beam fabricated from a fiber reinforced plastic composite (FRPC). The FRPC beam is a structural repair component intended to bridge a deteriorated thermal crack in full depth bituminous pavements or partial depth bituminous pavements over portland cement concrete. The bridging action provided by the FRPC beam is intended to minimize roughness through the repaired area for up to five years, eliminate reappearance of the deteriorated crack, and provide a controlled expansion crack that can be treated with standard sealing techniques. This apparatus is designed for maintenance use as a field expedient, semi-permanent repair using tools that are commonly available at the Area Maintenance level. Three FRPC beams were constructed for field trial in a thermally cracked, full depth bituminous pavement on US-36 east of Hiawatha, Kansas. Each of the beams were instrumented with bonded metal foil strain gages and field installation by KDOT Maintenance forces was done in August and September of 1997. The FRPC beams have been evaluated since installation and this evaluation will continue for up to five years. Evaluation of the beams has been accomplished through static load tests using the strain gage instrumentation and Falling Weight Deflectometer measurements. The FRPC beams have performed satisfactorily as of the date of writing.

  8. Characterization of nanoparticles released during construction of photocatalytic pavements using engineered nanoparticles

    NASA Astrophysics Data System (ADS)

    Dylla, Heather; Hassan, Marwa M.

    2012-03-01

    With the increasing use of titanium dioxide (TiO2) nanoparticles in self-cleaning materials such as photocatalytic concrete pavements, the release of nanoparticles into the environment is inevitable. Nanoparticle concentration, particle size, surface area, elemental composition, and surface morphology are pertinent to determine the associated risks. In this study, the potential of exposure to synthetic nanoparticles released during construction activities for application of photocatalytic pavements was measured during laboratory-simulated construction activities of photocatalytic mortar overlays and in an actual field application of photocatalytic spray coat. A scanning mobility particle sizer system measured the size distribution of nanoparticles released during laboratory and field activities. Since incidental nanoparticles are released during construction activities, nanoparticle emissions were compared to those from similar activities without nano-TiO2. Nanoparticle counts and size distribution suggest that synthetic nanoparticles are released during application of photocatalytic pavements. In order to identify the nanoparticle source, nanoparticles were also collected for offline characterization using transmission electron microscopy. However, positive identification of synthetic nanoparticles was not possible due to difficulties in obtaining high-resolution images. As a result, further research is recommended to identify nanoparticle composition and sources.

  9. Effects of composition and exposure on the solar reflectance of Portland cement concrete

    SciTech Connect

    Levinson, Ronnen; Akbari, Hashem

    2001-12-21

    Increasing the solar reflectance (albedo) of a paved surface keeps it cooler in the sun, reducing convection of heat from pavement to air and thereby decreasing the ambient air temperature. Simulations of the influence of pavement albedo on air temperature in Los Angeles predict that increasing the albedo of 1,250 km2 of pavement by 0.25 would save cooling energy worth $15M yr-1, and reduce smog-related medical and lost-work expenses by $76M yr-1. Most sidewalks and a small fraction of roads and parking areas are paved with portland cement concrete, which can be made quite reflective through suitable choice of cement and aggregate. Variations with composition and environmental exposure of the albedos of portland cement concrete pavements were investigated through laboratory fabrication and exposure of 32 mixes of concrete. Twenty-four mixes yielded substandard, ''rough'' concretes due to high, unmet aggregate water demand. The albedos of the remaining eight ''smooth'' concrete mixes ranged from 0.41 to 0.77 (mean 0.59). Simulated weathering, soiling, and abrasion each reduced average concrete albedo (mean decreases 0.06, 0.05, and 0.19, respectively), though some samples became slightly more reflective through weathering or soiling. Simulated rain (wetting) strongly depressed the albedos of concretes (mean decrease 0.23) until their surfaces were dried. Concrete albedo grew as the cement hydration reaction progressed (mean increase 0.08), but stabilized within six weeks of casting. White-cement concretes were on average significantly more reflective than gray-cement concretes. The albedo of the most-reflective white-cement concrete was 0.18 to 0.39 higher than that of the most-reflective gray-cement concrete, depending on state of exposure. Concrete albedo generally correlated with cement albedo and sand albedo, and, after abrasion, with rock albedo. Cement albedo had a disproportionately strong influence on the reflectance of concrete. Efflorescence and surface

  10. 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.

  11. Numerical study on the curling and warping of hardened rigid pavement slabs

    NASA Astrophysics Data System (ADS)

    Qin, Yinghong

    In-service hardened concrete pavement suffers from environmental loadings caused by curling and warping of the slab. Traditionally, these loadings are computed on the basis of treating the slab as an elastic material, and of evaluating separately the curling and warping components. This dissertation simulates temperature distribution and moisture distribution through the slabs by use of a developed numerical model that couples the heat transfer and moisture transport. The computation of environmental loadings treats the slab as an elastic-viscous material, which considers the relaxation behavior and Pickett effect of the concrete. The heat transfer model considers the impacts of solar radiation, wind speed, air temperature, pavement slab albedo, etc. on the pavement temperature distribution. This dissertation assesses the difference between documented models that aim to predict pavement temperature, highlighting their pros and cons. The moisture transport model is unique for the documented models; it mimics the wetting and drying events occurring at the slab surface. These events are estimated by a proposed statistical algorithm, which is verified by field rainfall data. Analysis of the predicted results examines on the roles of the local air RH (relative humidity), wind speed, rainy pattern in the moisture distribution through the slab. The findings reveal that seasonal air RH plays a decisive role on the slab's moisture distribution; but wind speed and its daily variation, daily RH variation, and seasonal rainfall pattern plays only a secondary role. This dissertation sheds light on the computation of environmental loadings that in-service pavement slabs suffer from. Analysis of the computed stresses centers on the stress relaxation near the surface, stress evolution after the curing ends, and the impact of construction season on the stress's magnitude. An unexpected finding is that the total environmental loadings at the cyclically-stable state divert from the

  12. Longitudinal joint systems in slip-formed rigid pavements. Volume 4: Recommendations for alternate joint systems and for strengthening existing joints

    NASA Astrophysics Data System (ADS)

    Korbus, L.; Barenberg, E. J.

    1981-11-01

    Load transfer across joints is a key factor in the performance of PCC pavements. The common load transfer devices in longitudinal joints for airport pavements have for many years been concrete keyways. Many of these keyways fail under heavy aircraft loads and are very difficult to construct using slip-formed pavers. Alternate joint systems which are potentially more reliable than keyways and which can be constructed using slip-formed pavers are presented in the report. Also, procedures are described for retrofitting existing slabs with devices to provide load transfer across joints or cracks. Laboratory and field tests with these load transfer devices are described, and data on their performance are presented. Recommendations for joint designs for PCC airport pavements are given based on the level of traffic anticipated.

  13. Porous pavement. Phase 1: Design and operational criteria

    NASA Astrophysics Data System (ADS)

    Diniz, E. V.

    1980-08-01

    Utilization concepts, benefits and disadvantages, as well as other characteristics of porous pavements are presented with emphasis on porous asphalt pavements, but the criteria and design approach are applicable to all other porous pavement types. Design considerations include siting problems, load bearing design and hydrologic design. The history of porous pavement development and previous experience with porous pavement by several designers, contractors and operators are described. A computer model for hydrologic performance evaluation of existing or proposed porous pavement systems is also examined. Load bearing design criteria are based on previous work conducted for porous asphalt pavements. Appendices include a sample set of specifications for porous asphalt construction and a list of soils and their permeability classes as prepared by the U.S. Soil Conservation Service.

  14. An Evaluation of the Pavement Condition Index Prediction Model for Flexible Airfield Pavements.

    DTIC Science & Technology

    1983-09-01

    NO. 3 . RECiPIENT’S CATALOG NUMBER LSSR 11-83 LID,_ 13 -______9_ 4. TITLE (end Subtitle) S. TYPE OF REPORT & PERIOD COVERED AN EVALUATION OF THE...Flexible Models. ......... 42 Current Model Development ...........54 Dronen Model................67 Conclusion ................... 71 iv CHAPTER Page 3 ...13 2-2 General Guide for Establishing Rigid Pavement Condition................16 2- 3 Types of Distress in Airfield Pavement

  15. 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.

  16. Ultrasound data for laboratory calibration of an analytical model to calculate crack depth on asphalt pavements.

    PubMed

    Franesqui, Miguel A; Yepes, Jorge; García-González, Cándida

    2017-08-01

    This article outlines the ultrasound data employed to calibrate in the laboratory an analytical model that permits the calculation of the depth of partial-depth surface-initiated cracks on bituminous pavements using this non-destructive technique. This initial calibration is required so that the model provides sufficient precision during practical application. The ultrasonic pulse transit times were measured on beam samples of different asphalt mixtures (semi-dense asphalt concrete AC-S; asphalt concrete for very thin layers BBTM; and porous asphalt PA). The cracks on the laboratory samples were simulated by means of notches of variable depths. With the data of ultrasound transmission time ratios, curve-fittings were carried out on the analytical model, thus determining the regression parameters and their statistical dispersion. The calibrated models obtained from laboratory datasets were subsequently applied to auscultate the evolution of the crack depth after microwaves exposure in the research article entitled "Top-down cracking self-healing of asphalt pavements with steel filler from industrial waste applying microwaves" (Franesqui et al., 2017) [1].

  17. Characterisation of an unprocessed landfill ash for application in concrete.

    PubMed

    Snelson, David G; Kinuthia, John M

    2010-11-01

    An investigation was carried out to establish the physical, mechanical and durability characteristics of an unprocessed pulverised fuel ash (PFA) from a former landfill site at the Power Station Hill near Church Village, South Wales, United Kingdom. This was aimed at establishing the suitability of the ash in the construction of the Church Village Bypass (embankment and pavement) and also in concrete to be used in the construction of the proposed highway. Concrete made using binder blends using various levels of PFA as replacement to Portland cement (PC) were subjected to compressive strength tests to establish performance. The concrete was also subjected to sodium sulphate attack by soaking concrete specimens in sulphate solution to establish performance in a sulphatic environment. Strength development up to 365 days for the concrete made with PC-PFA blends as binders (PC-PFA concrete), and 180 days for the PC-PFA paste, is reported. The binary PC-PFA concrete did not show good early strength development, but tended to improve at longer curing periods. The low early strength observed means that PC-PFA concrete can be used for low to medium strength applications for example blinding, low-strength foundations, crash barriers, noise reduction barriers, cycle paths, footpaths and material for pipe bedding. Copyright 2010 Elsevier Ltd. All rights reserved.

  18. Self-assembling particle-siloxane coatings for superhydrophobic concrete.

    PubMed

    Flores-Vivian, Ismael; Hejazi, Vahid; Kozhukhova, Marina I; Nosonovsky, Michael; Sobolev, Konstantin

    2013-12-26

    We report here, for the first time in the literature, a method to synthesize hydrophobic and superhydrophobic concrete. Concrete is normally a hydrophilic material, which significantly reduces the durability of concrete structures and pavements. To synthesize water-repellent concrete, hydrophobic emulsions were fabricated and applied on portland cement mortar tiles. The emulsion was enriched with the polymethyl-hydrogen siloxane oil hydrophobic agent as well as metakaolin (MK) or silica fume (SF) to induce the microroughness and polyvinyl alcohol (PVA) fibers to create hierarchical surfaces. Various emulsion types were investigated by using different mixing procedures, and single- and double-layer hydrophobic coatings were applied. The emulsions and coatings were characterized with optical microscope and scanning electron microscope (SEM), and their wetting properties, including the water contact angle (CA) and roll-off angle, were measured. A theoretical model for coated and non-coated concrete, which can be generalized for other types of materials, was developed to predict the effect of surface roughness and composition on the CA. An optimized distance between the aggregates was found where the CA has the highest value. The maximal CA measured was 156° for the specimen with PVA fibers treated with MK based emulsion. Since water penetration is the main factor leading to concrete deterioration, hydrophobic water-repellent concretes have much longer durability then regular concretes and can have a broad range of applications in civil and materials engineering.

  19. Maintenance measures for preservation and recovery of permeable pavement surface infiltration rate--The effects of street sweeping, vacuum cleaning, high pressure washing, and milling.

    PubMed

    Winston, Ryan J; Al-Rubaei, Ahmed M; Blecken, Godecke T; Viklander, Maria; Hunt, William F

    2016-03-15

    The surface infiltration rates (SIR) of permeable pavements decline with time as sediment and debris clog pore spaces. Effective maintenance techniques are needed to ensure the hydraulic functionality and water quality benefits of this stormwater control. Eight different small-scale and full-scale maintenance techniques aimed at recovering pavement permeability were evaluated at ten different permeable pavement sites in the USA and Sweden. Maintenance techniques included manual removal of the upper 2 cm of fill material, mechanical street sweeping, regenerative-air street sweeping, vacuum street sweeping, hand-held vacuuming, high pressure washing, and milling of porous asphalt. The removal of the upper 2 cm of clogging material did not significantly improve the SIR of concrete grid paves (CGP) and permeable interlocking concrete pavers (PICP) due to the inclusion of fines in the joint and bedding stone during construction, suggesting routine maintenance cannot overcome improper construction. For porous asphalt maintenance, industrial hand-held vacuum cleaning, pressure washing, and milling were increasingly successful at recovering the SIR. Milling to a depth of 2.5 cm nearly restored the SIR for a 21-year old porous asphalt pavement to like-new conditions. For PICP, street sweepers employing suction were shown to be preferable to mechanical sweepers; additionally, maintenance efforts may become more intensive over time to maintain a threshold SIR, as maintenance was not 100% effective at removing clogging material.

  20. Statistical variations in impact resistance of steel fiber-reinforced concrete subjected to drop weight test

    SciTech Connect

    Nataraja, M.C.; Dhang, N.; Gupta, A.P.

    1999-07-01

    The variation in impact resistance of steel fiber-reinforced concrete and plain concrete as determined from a drop weight test is reported. The observed coefficients of variation are about 57 and 46% for first-crack resistance and the ultimate resistance in the case of fiber concrete and the corresponding values for plain concrete are 54 and 51%, respectively. The goodness-of-fit test indicated poor fitness of the impact-resistance test results produced in this study to normal distribution at 95% level of confidence for both fiber-reinforced and plain concrete. However, the percentage increase in number of blows from first crack to failure for both fiber-reinforced concrete and as well as plain concrete fit to normal distribution as indicated by the goodness-of-fit test. The coefficient of variation in percentage increase in the number of blows beyond first crack for fiber-reinforced concrete and plain concrete is 51.9 and 43.1%, respectively. Minimum number of tests required to reliably measure the properties of the material can be suggested based on the observed levels of variation.

  1. 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.

  2. Stabilized fiber-reinforced pavement base course with recycled aggregate

    NASA Astrophysics Data System (ADS)

    Sobhan, Khaled

    's assumptions for rigid pavements), which has been found to explain reasonably well the field behavior of unreinforced and fiber-reinforced concrete slabs on grade. Finally, a preliminary cost analysis demonstrated that the use of stabilized recycled aggregate instead of a standard crushed stone base course can result in a meaningful economic savings.

  3. Properties of concrete made with north carolina recycled coarse and fine aggregates. Final report, 1 July 1994-30 June 1996

    SciTech Connect

    Ahmad, S.H.; Fisher, D.G.; Sackett, K.W.

    1996-06-30

    Reconstruction of roadways generates large quantities of waste material and requires considerable amounts of aggregate. The recycling of concrete from old deteriorated pavements into aggregates for construction of new pavements reduces disposal costs as well as providing a source of aggregates to replace natural supplies. In this study, recycled coarse and fine aggregates were obtained from a portion of concrete pavement which was removed from Interstate 40 in North Carolina. Various amounts of recycled coarse and fine aggregates were volumerically substituted for natural coarse and fine aggregates of a control mixture. A relatively higher cement factor was used for the control mix, compared to NCDOT standard. The effects on plastic and hardened concrete properties were investigated.

  4. Pavement management and weigh-in-motion. Transportation research record

    SciTech Connect

    Cation, K.A.; Shahin, M.Y.; Scullion, T.; Lytton, R.L.; Butt, A.A.

    1987-01-01

    The 15 papers in the report deal with the following areas: development of a preventive maintenance algorithm for use in pavement-management systems; pavement-performance prediction model using the Markov Process; roadway modeling and data conversion for a transportation-facilities information system; development of a methodology to estimate pavement maintenance and repair costs for different ranges of pavement-condition index; new techniques for modeling pavement deterioration; pavement management at the local government level; a comprehensive ranking system for local-agency pavement management; expert system as a part of pavement management; MAPCON: a pavement-evaluation data-analysis computer system; a microcomputer procedure to analyze axle load limits and pavement damage responsibility; selected results from the first three years of the Oregon automatic monitoring demonstration project; automated acquisition of truck-tire pressure data; calibration and accuracy testing of weigh-in-motion systems; accuracy and tolerances of weigh-in-motion systems; on-site calibration of weigh-in-motion systems.

  5. Epoxy asphalt concrete is a perspective material for the construction of roads

    NASA Astrophysics Data System (ADS)

    Vyrozhemskyi, Valerii; Kopynets, Ivan; Kischynskyi, Sergii; Bidnenko, Nataliia

    2017-09-01

    An effective way to increase the durability of asphalt concrete pavements that are subject to high traffic loads and adverse weather and climatic factors is the use of polymer additives which drastically improve the rheological and physical-mechanical properties of bitumen. The use of thermosetting polymers including epoxy resins for asphalt and bitumen modification is seen as a perspective solution for this issue. Conducted at DerzhdorNDI SE studies have proved high riding qualities of asphalt pavements that contain epoxy resins. When replacing 20-35% of bitumen with epoxy component, a significant improvement in strength characteristics of asphalt pavement is noted, especially at elevated temperatures. Specific feature of epoxy asphalt concrete is its ability to gain strength over a long-term operation. Thus, despite the increased cost of epoxy asphalt concrete, long service life of pavements on its basis (up to 30 years as predicted) ensures a high profitability of using this material, especially on the roads with heavy traffic and severe traffic conditions.

  6. The optimization of concrete mixtures for use in highway applications

    NASA Astrophysics Data System (ADS)

    Moini, Mohamadreza

    Portland cement concrete is most used commodity in the world after water. Major part of civil and transportation infrastructure including bridges, roadway pavements, dams, and buildings is made of concrete. In addition to this, concrete durability is often of major concerns. In 2013 American Society of Civil Engineers (ASCE) estimated that an annual investment of 170 billion on roads and 20.5 billion for bridges is needed on an annual basis to substantially improve the condition of infrastructure. Same article reports that one-third of America's major roads are in poor or mediocre condition [1]. However, portland cement production is recognized with approximately one cubic meter of carbon dioxide emission. Indeed, the proper and systematic design of concrete mixtures for highway applications is essential as concrete pavements represent up to 60% of interstate highway systems with heavier traffic loads. Combined principles of material science and engineering can provide adequate methods and tools to facilitate the concrete design and improve the existing specifications. In the same manner, the durability must be addressed in the design and enhancement of long-term performance. Concrete used for highway pavement applications has low cement content and can be placed at low slump. However, further reduction of cement content (e.g., versus current specifications of Wisconsin Department of Transportation to 315-338 kg/m 3 (530-570 lb/yd3) for mainstream concrete pavements and 335 kg/m3 (565 lb/yd3) for bridge substructure and superstructures) requires delicate design of the mixture to maintain the expected workability, overall performance, and long-term durability in the field. The design includes, but not limited to optimization of aggregates, supplementary cementitious materials (SCMs), chemical and air-entraining admixtures. This research investigated various theoretical and experimental methods of aggregate optimization applicable for the reduction of cement content

  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. Stochastic finite element applications in rigid pavement performance

    NASA Astrophysics Data System (ADS)

    Attoh-Okine, Nii O.

    1999-05-01

    Rigid pavement structures have uncertainties and variability in their structural layers and components. These variations and uncertainties are seldomly included in performance assessment and evaluation in pavement systems. This paper proposes to use Stochastic Finite Element Method (SFEM) in rigid pavement faulting and load transfer efficiency. The SFEM uses random parameters, as stochastic process namely random fields. These random fields are characterized, quantitatively by spatial functions of statistical moment like the mean, variance and covariance.

  9. The impact of material characteristics on tire pavement interaction noise for flexible pavements

    NASA Astrophysics Data System (ADS)

    Kocak, Salih

    Noise pollution has recently been one of the growing problems all over the world. While there are many sources of the noise, traffic noise is the main contributor to the total environmental noise. Although there are different sources for traffic noise, the tire pavement interaction noise is the most dominant component within most city and highway limits. One of the ways to reduce the tire pavement noise is to improve the material characteristics of the pavements such that they produce less noise. In this study, the relationship between basic material characteristics (e.g., Hot Mix Asphalt (HMA) volumetrics) and sound generation and absorption characteristics of flexible pavements was investigated. In addition, the effect of linear visco-elastic properties (e.g., dynamic modulus (|E*|) and phase angle (delta)) on sound absorption was studied. In order to focus only on impact of material characteristics and overshadow the effect of surface texture, a novel laboratory tire pavement noise measurement simulator (TIPANOS) was developed. The statistical analysis results showed that although the individual material characteristics do not have appreciable influence on sound absorption, there is a significant correlation between sound pressure levels (SPL) and combination of several material and linear visco-elastic parameters.

  10. Study on Flexible Pavement Failures in Soft Soil Tropical Regions

    NASA Astrophysics Data System (ADS)

    Jayakumar, M.; Chee Soon, Lee

    2015-04-01

    Road network system experienced rapid upgrowth since ages ago and it started developing in Malaysia during the colonization of British due to its significant impacts in transportation field. Flexible pavement, the major road network in Malaysia, has been deteriorating by various types of distresses which cause descending serviceability of the pavement structure. This paper discusses the pavement condition assessment carried out in Sarawak and Sabah, Malaysia to have design solutions for flexible pavement failures. Field tests were conducted to examine the subgrade strength of existing roads in Sarawak at various failure locations, to assess the impact of subgrade strength on pavement failures. Research outcomes from field condition assessment and subgrade testing showed that the critical causes of pavement failures are inadequate design and maintenance of drainage system and shoulder cross fall, along with inadequate pavement thickness provided by may be assuming the conservative value of soil strength at optimum moisture content, whereas the exiting and expected subgrade strengths at equilibrium moisture content are far below. Our further research shows that stabilized existing recycled asphalt and base materials to use as a sub-base along with bitumen stabilized open graded base in the pavement composition may be a viable solution for pavement failures.

  11. Crack identification for rigid pavements using unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Bahaddin Ersoz, Ahmet; Pekcan, Onur; Teke, Turker

    2017-09-01

    Pavement condition assessment is an essential piece of modern pavement management systems as rehabilitation strategies are planned based upon its outcomes. For proper evaluation of existing pavements, they must be continuously and effectively monitored using practical means. Conventionally, truck-based pavement monitoring systems have been in-use in assessing the remaining life of in-service pavements. Although such systems produce accurate results, their use can be expensive and data processing can be time consuming, which make them infeasible considering the demand for quick pavement evaluation. To overcome such problems, Unmanned Aerial Vehicles (UAVs) can be used as an alternative as they are relatively cheaper and easier-to-use. In this study, we propose a UAV based pavement crack identification system for monitoring rigid pavements’ existing conditions. The system consists of recently introduced image processing algorithms used together with conventional machine learning techniques, both of which are used to perform detection of cracks on rigid pavements’ surface and their classification. Through image processing, the distinct features of labelled crack bodies are first obtained from the UAV based images and then used for training of a Support Vector Machine (SVM) model. The performance of the developed SVM model was assessed with a field study performed along a rigid pavement exposed to low traffic and serious temperature changes. Available cracks were classified using the UAV based system and obtained results indicate it ensures a good alternative solution for pavement monitoring applications.

  12. A novel micromechanics based approach in modeling pavement response

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Arun

    For maintaining a smooth flow of traffic in the nation's highway system, sections of pavements that are damaged need to be serviced frequently. Among the various types of damage, those caused by heavy trucks are a major concern. Based on a detailed and broad literature survey, it is apparent that no analytical model exists which could closely predict dynamic pavement response and progressive damage, even qualitatively, due to truck loading. It is such a model that is developed in this work. In order to predict pavement response and damage analytically, a model will have to be based on a theory that captures the essential features of the pavement material. The state-of-the-art Microplane Theory, which has never been applied before to pavement, is chosen to model the material behavior in this research. The theory is implemented in a finite element code to predict tri-axial pavement response. The pavement material damage due to traffic loading is also presented qualitatively. Furthermore, using Taguchi Methods, the critical parameters in a pavement design are determined. Finally, the response of pavement to various joint designs parameters is evaluated.

  13. Sustainable construction: Composite use of tyres and ash in concrete

    SciTech Connect

    Snelson, D.G.; Kinuthia, J.M.; Davies, P.A.; Chang, S.R.

    2009-01-15

    An investigation was carried out to establish the physical, mechanical and chemical characteristics of a non-standard (unprocessed) pulverised fuel ash (PFA) and waste tyres from a former landfill site at the Power Station Hill near Church Village, South Wales, United Kingdom. Investigations are on-going to establish the suitability of the fly ash and/or tyres in road construction (embankment and pavement) and also in concrete to be used in the construction of the proposed highway. This paper reports on concrete-based construction where concrete blends (using various levels of PFA as partial replacement for Portland cement (PC), and shredded waste tyres (chips 15-20 mm) as aggregate replacement) were subjected to unconfined compressive strength tests to establish performance, hence, optimising mix designs. Strength development up to 180 days for the concrete made with PC-PFA blends as binders (PC-PFA concrete), with and without aggregate replacement with tyre chips, is reported. The binary PC-PFA concrete does not have good early strength but tends to improve at longer curing periods. The low early strength observed means that PC-PFA concrete cannot be used for structures, hence, only as low to medium strength applications such as blinding, low-strength foundations, crash barriers, noise reduction barriers, cycle paths, footpaths and material for pipe bedding.

  14. Sustainable construction: composite use of tyres and ash in concrete.

    PubMed

    Snelson, D G; Kinuthia, J M; Davies, P A; Chang, S-R

    2009-01-01

    An investigation was carried out to establish the physical, mechanical and chemical characteristics of a non-standard (unprocessed) pulverised fuel ash (PFA) and waste tyres from a former landfill site at the Power Station Hill near Church Village, South Wales, United Kingdom. Investigations are on-going to establish the suitability of the fly ash and/or tyres in road construction (embankment and pavement) and also in concrete to be used in the construction of the proposed highway. This paper reports on concrete-based construction where concrete blends (using various levels of PFA as partial replacement for Portland cement (PC), and shredded waste tyres (chips 15-20mm) as aggregate replacement) were subjected to unconfined compressive strength tests to establish performance, hence, optimising mix designs. Strength development up to 180 days for the concrete made with PC-PFA blends as binders (PC-PFA concrete), with and without aggregate replacement with tyre chips, is reported. The binary PC-PFA concrete does not have good early strength but tends to improve at longer curing periods. The low early strength observed means that PC-PFA concrete cannot be used for structures, hence, only as low to medium strength applications such as blinding, low-strength foundations, crash barriers, noise reduction barriers, cycle paths, footpaths and material for pipe bedding.

  15. Design of Road Pavement Using Recycled Aggregate

    NASA Astrophysics Data System (ADS)

    Remišová, Eva; Decký, Martin; Mikolaš, Milan; Hájek, Matej; Kovalčík, Luboš; Mečár, Martin

    2016-10-01

    The presented article gives special attention to codified clauses of the road construction law, the relevant clauses of the standards and technical regulations to design and control the quality of recycled aggregate constructions. The article also presents the authors’ suggestions to design of earth constructions and pavements of roads according to the Slovak technical standards, technical regulations and objectively determined results of research and development of road infrastructure. The article presents a comparison of the mechanical characteristics measurements of the structural layers of road pavements built from the recycled and natural aggregate. It also presents correlation functions of results obtained from in situ and in laboratory CBR (Californian Bearing Ratio) measuring, representing the world's most widely used control method of bearing capacity of mentioned construction layers.

  16. Effectiveness of transverse grooves in rigid pavement

    NASA Astrophysics Data System (ADS)

    Gurney, G. F.; Bryden, J. E.

    1982-10-01

    Transverse grooves were installed at 11 intersection approaches on worn rigid pavement to reduce a high rate of wet road accidents. In most cases, accident reductions were experienced only at intersections with multiple negative operational characteristics, including higher approach speeds, limited sight distances, and frequent vehicle stopping for turns or stop signs. Intersections with no more than one negative characteristic generally did not benefit from grooving.

  17. Multimodal approach to seismic pavement testing

    USGS Publications Warehouse

    Ryden, N.; Park, C.B.; Ulriksen, P.; Miller, R.D.

    2004-01-01

    A multimodal approach to nondestructive seismic pavement testing is described. The presented approach is based on multichannel analysis of all types of seismic waves propagating along the surface of the pavement. The multichannel data acquisition method is replaced by multichannel simulation with one receiver. This method uses only one accelerometer-receiver and a light hammer-source, to generate a synthetic receiver array. This data acquisition technique is made possible through careful triggering of the source and results in such simplification of the technique that it is made generally available. Multiple dispersion curves are automatically and objectively extracted using the multichannel analysis of surface waves processing scheme, which is described. Resulting dispersion curves in the high frequency range match with theoretical Lamb waves in a free plate. At lower frequencies there are several branches of dispersion curves corresponding to the lower layers of different stiffness in the pavement system. The observed behavior of multimodal dispersion curves is in agreement with theory, which has been validated through both numerical modeling and the transfer matrix method, by solving for complex wave numbers. ?? ASCE / JUNE 2004.

  18. Full-Scale Accelerated Pavement Testing of Warm-Mix Asphalt (WMA) for Airfield Pavements

    DTIC Science & Technology

    2014-01-01

    software and Pavement Engineering Utility (PSEVEN) were used 50 ft 65 ft 130 ft 24 ft Item 3 Sasobit ® Item 4 Evotherm 3G Item 1 HMA... Evotherm 3G Air Top Mid-depth Bottom Target temperature = 109 ºF ERDC/GSL TR-14-3 25 The target pavement temperature for this study was 109 ºF, and it is...the locations of the I-buttons and their layout in relation to the vents. 90 95 100 105 110 115 120 HMA Foamed Asphalt Sasobit Evotherm 3G Av er ag e

  19. New structural systems for zero-maintenance pavements. Volume 2: Analysis of anchored pavements using ANSYS

    NASA Astrophysics Data System (ADS)

    Saxena, S. K.; Militsopoulos, S. G.

    1980-08-01

    A set of procedures to evaluate the response of an anchored pavement subjected to vehicle static loads, moisture variation in the subgrade, and/or temperature variation through the surface of the pavement is presented. These procedures include two computer programs known as FEMESH and ANSYS. The FEMESH program generates rectangular meshes in either a two or three dimensional coordinate system for any prespecified number and spacing of nodes. The ANSYS program evaluates the stresses, strains, and the deflections at all elements in each material included in the analytical model.

  20. Design of Overlays for Rigid Airport Pavements

    DTIC Science & Technology

    1988-04-01

    Renture, A., and Mindess , S. 1986. "The Effect of Concrete Strength on Crack Patterns," Cement and Concrete Research,_ Vol 16, Pergamon Press Ltd...34 Miscellaneous Paper S-74-30, US Army Engineer Waterways Experiment Station, Vicksburg, Miss. 22. Harr, M. E. 1977 . Mechanics of Particulate Media...of Civil -. Engineers, New York. 33. Hutchinson, R., and Vedros, P. 1977 . "Performance of Heavy-Load Port- land Cement Concrete (Rigid) Airfield

  1. Permeable Pavement Research at the Edison Environmental Center

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used permeable pavement systems. Practitioners need additional studies of permeable pavement systems in its intended application (parking lot, roadway, etc.) across a range of climatic events, daily usage conditio...

  2. Update to Permeable Pavement Research at the Edison ...

    EPA Pesticide Factsheets

    Brief Background of Edison Environmental Center in Edison, New Jersey Porous Pavement research at the Edison Environmental Center in Edison, New Jersey Publications and references Brief Background of Edison Environmental Center in Edison, New Jersey Porous Pavement research at the Edison Environmental Center in Edison, New Jersey

  3. Permeable pavement demonstration site at Edison Environmental Center (Presentation)

    EPA Science Inventory

    There are few studies of full-scale, outdoor, replicated, working pervious pavement systems. More studies of pervious pavement operating in its intended use (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions, and maintenance regimes are necessa...

  4. Nutrient Infiltrate Concentrations from Three Permeable Pavement Types

    EPA Science Inventory

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha...

  5. Effect of induced deformation on NDT pavement evaluation

    NASA Astrophysics Data System (ADS)

    Tawfiq, Kamal S.; Sobanjo, John O.; Ruiz, R.

    1999-02-01

    Three nondestructive testing techniques were used in this study to evaluate pavement layer properties. These techniques included deflection and seismic methods. In the deflection methods, measurable surface deformations were induced using falling weight deflectometer and Dynaflect tests. These two tests utilized different schemes of dynamic loading applications to produce deflection basins from which the pavement layer properties were back calculated. Pavement properties from seismic methods were obtained from the analysis of surface waves due to transient load applications. In this study the seismic pavement analyzer (SPA) was used to determine pavement moduli values. Although the same assumptions for linear elastic behavior of pavement properties are usually assumed in all the three methods, obtained moduli values from these techniques did not conform to each other. Commonly, pavement deflection from SPA is not considered when analyzing layer properties. To narrow the gap between the obtained results, however, time-history records and frequency response functions were used to determine surface deflections from the three methods. Deflection measurements correlated with the obtained moduli values. Using these correlations, moduli values at any pavement deflection levels could be evaluated, especially at levels produced by traffic loads.

  6. Modeling the Hydrologic Processes of a Permeable Pavement System

    EPA Science Inventory

    A permeable pavement system can capture stormwater to reduce runoff volume and flow rate, improve onsite groundwater recharge, and enhance pollutant controls within the site. A new unit process model for evaluating the hydrologic performance of a permeable pavement system has be...

  7. 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,…

  8. Development of a Portable Pavement Thickness/Density Meter (PTDM)

    NASA Astrophysics Data System (ADS)

    Maser, K. R.

    2002-08-01

    The Pavement Thickness/Density Meter (PTDM) concept developed in this research represents a new and innovative method for automatically determining pavement thickness and density. Pavement thickness and pavement density are two key variables that determine the future life and performance of asphalt pavement. In many cases, due to variations in placement conditions, the actual in-place thickness and density can vary considerably from specifications. Current testing methods based on coring are time consuming and do not provide adequate coverage. The PTDM system provides a means for quickly obtaining complete thickness/density coverage assessment of the pavement. The device is transportable and easily operated with limited training. It provides continuous data, in the form of profiles of the pavement thickness and density as a function of distance along the pavement. The method is safe, since it is based on low-powered pulsed electromagnetic waves. The key technological innovations required for the development of the PTDM are (1) the implementation of small and more portable components, particularly the transmitting antenna; (2) the implementation of software which automatically produces the readings that will be directly displayed for the operator; and (3) the packaging of all of these components in a small portable device that can be easily used and handled as a routine piece of field test equipment. The work carried out under this program has successfully achieved objectives (1) and (2).

  9. Permeable Pavement Research at the Edison Environmental Center

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used permeable pavement systems. Practitioners need additional studies of permeable pavement systems in its intended application (parking lot, roadway, etc.) across a range of climatic events, daily usage conditio...

  10. Electro-optical approach to pavement deflection management

    NASA Astrophysics Data System (ADS)

    Rish, Jeff W., III; Adcock, Avery D.; Tuan, Christopher Y.; Baker, Samuel L.; Welker, Hugh W., II; Johnson, Roger F.

    1995-07-01

    A prototype continuous deflection device, referred to as a rolling weight deflectometer (RWD), has been developed as a nondestructive evaluation tool for airfield pavements. The system consists of a rigid trailer equipped with specially designed optical triangulation pavement sensors, a high-speed data acquisition system, and a high-pressure tire/load platform assembly. Pavement sensors are mounted on a rigid box beam equipped with an internal sensor system that corrects, in real time, the relative pavement height position measurements for displacements induced in the beam by mechanical vibrations, changes in temperature, or nonuniform dynamic loads at points where the beam attaches to the frame. The device produces continuous deflection profiles that show pavement response to a moving loaded wheel along the path of travel. These deflection profiles, combined with multiple passes along a lane, provide a far more detailed picture of the pavement structural integrity than has ever before been possible, because existing evaluation tools only produce response information at discrete points. Preliminary results show deflections measured by the RWD are in general agreement with the expected pavement response for various loads. A discussion of the device configuration, preliminary data, and potential as a pavement management tool is presented.

  11. Permeable Pavement Demonstration at the Edison Environmental Center (Hartford)

    EPA Science Inventory

    In general, there is a lack of full-scale, outdoor, real-world porous pavement studies with system replicates. More studies of porous pavement operating in its intended use (parking lot, roadway, etc.) with climatic events, regular use, and maintenance effects, are necessary. The...

  12. Permeable pavement demonstration at the Edison Environmental Center

    EPA Science Inventory

    There are few studies of full-scale, outdoor, replicated, functioning pervious pavement systems. More studies of pervious pavement operating in its intended use (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions, and maintenance regimes are nec...

  13. Permeable Pavement Monitoring at the Edison Environmental Center Demonstration Site

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used pervious pavement systems. Practitioners need additional studies of pervious pavement systems in its intended application (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions...

  14. Permeable pavement demonstration at the Edison Environmental Center (Hartford, CT)

    EPA Science Inventory

    In general, there is a lack of full-scale, outdoor, real-world porous pavement studies with system replicates. More studies of porous pavement operating in its intended use (parking lot, roadway, etc.) with climatic events, regular use, and maintenance effects, are necessary. The...

  15. Permeable pavement monitoring at the Edison Environmental Center demonstration site

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used pervious pavement systems. Practitioners need additional studies of pervious pavement systems in its intended application (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions...

  16. Permeable pavement monitoring at the Edison Environmental Center demonstration site

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used pervious pavement systems. Practitioners need additional studies of pervious pavement systems in its intended application (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions...

  17. Permeable pavement demonstration site at Edison Environmental Center (Presentation)

    EPA Science Inventory

    There are few studies of full-scale, outdoor, replicated, working pervious pavement systems. More studies of pervious pavement operating in its intended use (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions, and maintenance regimes are necessa...

  18. Permeable Pavement Monitoring at the Edison Environmental Center Demonstration Site

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used pervious pavement systems. Practitioners need additional studies of pervious pavement systems in its intended application (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions...

  19. Permeable pavement demonstration at the Edison Environmental Center

    EPA Science Inventory

    There are few studies of full-scale, outdoor, replicated, functioning pervious pavement systems. More studies of pervious pavement operating in its intended use (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions, and maintenance regimes are nec...

  20. Nutrient Infiltrate Concentrations from Three Permeable Pavement Types

    EPA Science Inventory

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha...

  1. Permeable Pavement Demonstration at the Edison Environmental Center (Hartford)

    EPA Science Inventory

    In general, there is a lack of full-scale, outdoor, real-world porous pavement studies with system replicates. More studies of porous pavement operating in its intended use (parking lot, roadway, etc.) with climatic events, regular use, and maintenance effects, are necessary. The...

  2. Permeable pavement demonstration at the Edison Environmental Center (Hartford, CT)

    EPA Science Inventory

    In general, there is a lack of full-scale, outdoor, real-world porous pavement studies with system replicates. More studies of porous pavement operating in its intended use (parking lot, roadway, etc.) with climatic events, regular use, and maintenance effects, are necessary. The...

  3. Modeling the Hydrologic Processes of a Permeable Pavement System

    EPA Science Inventory

    A permeable pavement system can capture stormwater to reduce runoff volume and flow rate, improve onsite groundwater recharge, and enhance pollutant controls within the site. A new unit process model for evaluating the hydrologic performance of a permeable pavement system has be...

  4. The effect of different surface materials on runoff quality in permeable pavement systems.

    PubMed

    Li, Haiyan; Li, Zhifei; Zhang, Xiaoran; Li, Zhuorong; Liu, Dongqing; Li, Tanghu; Zhang, Ziyang

    2017-07-20

    To investigate the effect of different permeable pavement surface materials on the removal of pollutants from urban storm-runoff, six commonly surface materials (porous asphalt, porous concrete, cement brick, ceramic brick, sand base brick, and shale brick) were selected in this study and the research was carried out by column experiments. Except the concentrations of total suspended solids (TSS), chemical oxygen demand (COD), ammonia nitrogen (NH4-N), nitrate nitrogen (NO3-N), total nitrogen (TN), and total phosphorus (TP) in the influent and effluent that were measured, the removal mechanism of pollutants was discussed further. The results indicate that the surface materials influence the removal efficiency of pollutants greatly and have different effects on certain pollutant. Furthermore, the physical interception and adsorption would be the main mechanism for the removal of pollutants from runoff. For example, for all surface materials, the average removal efficiency of TSS is nearly about 90.0% because of physical interception. Due to the amount of iron oxide, the removal efficiency of COD, NO3-N, and TN of shale brick was 88.2, 35.1, and 17.5%, respectively. NH4-N and TN can be easily removed by porous asphalt due to the high content of organic matter. By lacking of useful adsorption sites, all the surface materials had little effect on the removal of TP from runoff. This research could offer useful guidelines for the better design of permeable pavement system and promote the insight into the removal mechanism of pollutants in permeable pavement system. Graphical abstract Different types of materials for the different types of pollutants in the runoff purification capacity were significantly different, overall, shale brick and porous asphalt Shale bricks and porous asphalt have a better purification effect according to the six kinds of materials.

  5. Respirable concrete dust--silicosis hazard in the construction industry.

    PubMed

    Linch, Kenneth D

    2002-03-01

    Concrete is an extremely important part of the infrastructure of modern life and must be replaced as it ages. Many of the methods of removing, repairing, or altering existing concrete structures have the potential for producing vast quantities of respirable dust. Since crystalline silica in the form of quartz is a major component of concrete, airborne respirable quartz dust may be produced during construction work involving the disturbance of concrete, thereby producing a silicosis hazard for exposed workers. Silicosis is a debilitating and sometimes fatal lung disease resulting from breathing microscopic particles of crystalline silica. Between 1992 and 1998, the National Institute for Occupational Safety and Health (NIOSH) made visits to construction projects where concrete was being mechanically disturbed in order to obtain data concerning respirable crystalline silica dust exposures. The construction activities studied included: abrasive blasting, concrete pavement sawing and drilling, and asphalt/concrete milling. Air samples of respirable dust were obtained using 10-mm nylon cyclone pre-separators, 37-mm polyvinyl chloride (PVC) filters, and constant-flow pumps calibrated at 1.7 L/min. In addition, high-volume respirable dust samples were obtained on 37-mm PVC filters using 1/2" metal cyclones (Sensidyne model 18) and constant-flow pumps calibrated at 9.0 L/min. Air sample analysis included total weight gain by gravimetric analysis according to NIOSH Analytical Method 600 and respirable crystalline silica (quartz and cristobalite) using x-ray diffraction, as per NIOSH Analytical Method 7500. For abrasive blasting of concrete structures, the respirable crystalline silica (quartz) concentration ranged up to 14.0 mg/m3 for a 96-minute sample resulting in an eight-hour time-weighted average (TWA) of 2.8 mg/m3. For drilling concrete highway pavement the respirable quartz concentrations ranged up to 4.4 mg/m3 for a 358-minute sample, resulting in an eight-hour TWA

  6. A Durability Analysis of Super-Quiet Pavement Structures

    NASA Astrophysics Data System (ADS)

    Srirangam, Santosh Kumar; Anupam, Kumar; Scarpas, Tom; Kasbergen, Cor; The, Peter

    Poro Elastic Road Surfacings (PERS) as a substitute for conventional noise barriers or other traditional pavement surfacings like open graded mixes are currently attracting significant attention. Ascertaining the durability of PERS material itself and its bonding with the underlying pavement layer against high traffic and high load intensities is of primary importance. In this contribution, results are presented of nonlinear finite element simulations of a high volume pavement profile comprised of a PERS top layer bonded to a conventional open asphalt top layer. Traffic loading was applied by means of a simulated truck tire moving load for various operating conditions. The paper focuses on investigation of the influence on the structural pavement response of various loading conditions and material properties of PERS and adhesive layer. The study concludes with guidelines for the optimum combination of design parameters that lead to increased durability of pavements constructed with a PERS top layer.

  7. Application of smart BFRP bars with distributed fiber optic sensors into concrete structures

    NASA Astrophysics Data System (ADS)

    Tang, Yongsheng; Wu, Zhishen; Yang, Caiqian; Wu, Gang; Zhao, Lihua; Song, Shiwei

    2010-04-01

    In this paper, the self-sensing and mechanical properties of concrete structures strengthened with a novel type of smart basalt fiber reinforced polymer (BFRP) bars were experimentally studied, wherein the sensing element is Brillouin scattering-based distributed optical fiber sensing technique. First, one of the smart bars was applied to strengthen a 2m concrete beam under a 4-points static loading manner in the laboratory. During the experiment, the bar can measure the inner strain changes and monitor the randomly distributed cracks well. With the distributed strain information along the bar, the distributed deformation of the beam can be calculated, and the structural health can be monitored and evaluated as well. Then, two smart bars with a length of about 70m were embedded into a concrete airfield pavement reinforced by long BFRP bars. In the field test, all the optical fiber sensors in the smart bars survived the whole concrete casting process and worked well. From the measured data, the concrete cracks along the pavement length can be easily monitored. The experimental results also confirmed that the bars can strengthen the structures especially after the yielding of steel bars. All the results confirm that this new type of smart BFRP bars show not only good sensing performance but also mechanical performance in the concrete structures.

  8. An Evaluation of the Pavement Condition Index Prediction Model for Rigid Airfield Pavements

    DTIC Science & Technology

    1982-09-01

    AC Thickness) -- Inches B THICK (Base Thickness) -- Inches SB THICK (Subbase Thickness) -- Inches B CBR (Base CBR) -- Percent SB CBR (Subbase CBR...vertical stress on the base course, surface deflection and vertical strain on top of •he subgrade was computed for asphalt pavements, using the Bitumen

  9. Utilization of Advanced Diagnostic Methods for Texture and Rut Depth Analysis on a Testing Pavement Section

    NASA Astrophysics Data System (ADS)

    Slabej, Martin; Grinč, Michal; Kotek, Peter; Kováč, Matúš; Decký, Martin

    2015-05-01

    Qualitative characteristics of pavement in wide range reflects the pavement serviceability, which is a summary of the characteristics of the pavement, providing a fast, smooth, economical and especially safe driving of motor-vehicles. The target factor of pavement serviceability and safety of roads represents the quality of their surface properties. In the framework of research activities performed in the Research Centre founded under the auspices of University of Žilina, individual parameters of pavement serviceability were monitored by pavement surface scanning. This paper describes the creation of a 3D - road surface model and its analysis and evaluation from the viewpoint of two pavement serviceability parameters - the rut depth and texture. Measurements were performed on an experimental pavement section used contemporary in an Accelerated Pavement Testing experiment. The long-term goal is to ascertain functions predicting degradation of these two pavement serviceability parameters.

  10. Strain transfer analysis of optical fiber based sensors embedded in an asphalt pavement structure

    NASA Astrophysics Data System (ADS)

    Wang, Huaping; Xiang, Ping

    2016-07-01

    Asphalt pavement is vulnerable to random damage, such as cracking and rutting, which can be proactively identified by distributed optical fiber sensing technology. However, due to the material nature of optical fibers, a bare fiber is apt to be damaged during the construction process of pavements. Thus, a protective layer is needed for this application. Unfortunately, part of the strain of the host material is absorbed by the protective layer when transferring the strain to the sensing fiber. To account for the strain transfer error, in this paper a theoretical analysis of the strain transfer of a three-layered general model has been carried out by introducing Goodman’s hypothesis to describe the interfacial shear stress relationship. The model considers the viscoelastic behavior of the host material and protective layer. The effects of one crack in the host material and the sensing length on strain transfer relationship are been discussed. To validate the effectiveness of the strain transfer analysis, a flexible asphalt-mastic packaged distributed optical fiber sensor was designed and tested in a laboratory environment to monitor the distributed strain and appearance of cracks in an asphalt concrete beam at two different temperatures. The experimental results indicated that the developed strain transfer formula can significantly reduce the strain transfer error, and that the asphalt-mastic packaged optical fiber sensor can successfully monitor the distributed strain and identify local cracks.

  11. Performance of an enhanced pervious pavement system loaded with large volumes of hydrocarbons.

    PubMed

    Newman, Alan P; Puehmeier, Tim; Shuttleworth, Andy; Pratt, Christopher J

    2014-01-01

    Five litres of lubricating oil and two 8.5 litre batches of diesel were deposited on each of two hydraulically isolated experimental enhanced pervious pavement parking bays. The 50 mm aggregate subbases of the two bays were of either recycled concrete or crushed limestone. The bays were constructed in such a way that a near-surface gravity separator was created by the arranging of the outlet pipes such that a permanent pool of water was maintained in the system and water could only enter from below the level of any floating oil. Dissolved/dispersed hydrocarbons were measured at acceptable concentrations when monitoring was carried out over a period of approximately 5 months. The maximum concentration was 7.2 mg/l and of all the samples collected only 3% exceeded the 5 mg/l limit applied in the UK for a class 1 interceptor, and the majority of samples had hydrocarbon concentrations of less than 2 mg/l. Much more significant is the fact that no free product was discharged from either system up to the time the experiment was dismantled 2 years from the first oil application despite the fact that sufficient hydrocarbon had been added to each pavement to produce a film on a water surface of over 500 hectares.

  12. Electrical resistance tomography for monitoring the infiltration of water into a pavement section

    SciTech Connect

    Buettner, M.; Daily, B.; Ramirez, A.

    1997-07-03

    Electrical resistance tomography (ERT) was used to follow the infiltration of water into pavement section at the UC Berkeley Richmond Field Station. A volume of pavement 1m square and 1.29 m deep was sampled by an ERT array consisting of electrodes in 9 drilled holes plus 8 surface electrodes. The data were collected using a computer controlled data acquisition system capable of collecting a full data set in under 1 hour, allowing for nearly real time sampling of the infiltration. The infiltration was conducted in two phases. During the first phase, water was introduced into the asphalt-concrete (AC) layers at a slow rate of about 8 ml per hour for a period of about 6 days. In the second phase, water was introduced into the asphalt-treated-permeable base (ATPB) layer at a more rapid rate of about 100 ml/h for about 2 days. The ERT images show that water introduced into the upper AC layers shows up as a decrease in resistivity which grows with time. The images also appear to show that when water moves into the layers below the ATPB, the resistivity increases; an unexpected result. There are some indications that the water moved laterally as well as down into the deeper ATPB and the aggregate base. The images also show that when water is introduced directly into the ATPB and aggregate layer, the water moves into the the underlying materials much more quickly.

  13. Refractory concretes

    DOEpatents

    Holcombe, Jr., Cressie E.

    1979-01-01

    Novel concrete compositions comprise particles of aggregate material embedded in a cement matrix, said cement matrix produced by contacting an oxide selected from the group of Y.sub.2 O.sub.3, La.sub.2 O.sub.3, Nd.sub.2 O.sub.3, Sm.sub.2 O.sub.3, Eu.sub.2 O.sub.3 and Gd.sub.2 O.sub.3 with an aqueous solution of a salt selected from the group of NH.sub.4 NO.sub.3, NH.sub.4 Cl, YCl.sub.3 and Mg(NO.sub.3).sub.2 to form a fluid mixture; and allowing the fluid mixture to harden.

  14. Analysis, testing and verification of the behavior of composite pavements under Florida conditions using a heavy vehicle simulator

    NASA Astrophysics Data System (ADS)

    Tapia Gutierrez, Patricio Enrique

    Whitetopping (WT) is a rehabilitation method to resurface deteriorated asphalt pavements. While some of these composite pavements have performed very well carrying heavy load, other have shown poor performance with early cracking. With the objective of analyzing the applicability of WT pavements under Florida conditions, a total of nine full-scale WT test sections were constructed and tested using a Heavy Vehicle Simulator (HVS) in the APT facility at the FDOT Material Research Park. The test sections were instrumented to monitor both strain and temperature. A 3-D finite element model was developed to analyze the WT test sections. The model was calibrated and verified using measured FWD deflections and HVS load-induced strains from the test sections. The model was then used to evaluate the potential performance of these test sections under critical temperature-load condition in Florida. Six of the WT pavement test sections had a bonded concrete-asphalt interface by milling, cleaning and spraying with water the asphalt surface. This method produced excellent bonding at the interface, with shear strength of 195 to 220 psi. Three of the test sections were intended to have an unbonded concrete-asphalt interface by applying a debonding agent in the asphalt surface. However, shear strengths between 119 and 135 psi and a careful analysis of the strain and the temperature data indicated a partial bond condition. The computer model was able to satisfactorily model the behavior of the composite pavement by mainly considering material properties from standard laboratory tests and calibrating the spring elements used to model the interface. Reasonable matches between the measured and the calculated strains were achieved when a temperature-dependent AC elastic modulus was included in the analytical model. The expected numbers of repetitions of the 24-kip single axle loads at critical thermal condition were computed for the nine test sections based on maximum tensile stresses

  15. Highly Conductive Carbon Fiber Reinforced Concrete for Icing Prevention and Curing.

    PubMed

    Galao, Oscar; Bañón, Luis; Baeza, Francisco Javier; Carmona, Jesús; Garcés, Pedro

    2016-04-12

    This paper aims to study the feasibility of highly conductive carbon fiber reinforced concrete (CFRC) as a self-heating material for ice formation prevention and curing in pavements. Tests were carried out in lab ambient conditions at different fixed voltages and then introduced in a freezer at -15 °C. The specimens inside the freezer were exposed to different fixed voltages when reaching +5 °C for prevention of icing and when reaching the temperature inside the freezer, i.e., -15 °C, for curing of icing. Results show that this concrete could act as a heating element in pavements with risk of ice formation, consuming a reasonable amount of energy for both anti-icing (prevention) and deicing (curing), which could turn into an environmentally friendly and cost-effective deicing method.

  16. Highly Conductive Carbon Fiber Reinforced Concrete for Icing Prevention and Curing

    PubMed Central

    Galao, Oscar; Bañón, Luis; Baeza, Francisco Javier; Carmona, Jesús; Garcés, Pedro

    2016-01-01

    This paper aims to study the feasibility of highly conductive carbon fiber reinforced concrete (CFRC) as a self-heating material for ice formation prevention and curing in pavements. Tests were carried out in lab ambient conditions at different fixed voltages and then introduced in a freezer at −15 °C. The specimens inside the freezer were exposed to different fixed voltages when reaching +5 °C for prevention of icing and when reaching the temperature inside the freezer, i.e., −15 °C, for curing of icing. Results show that this concrete could act as a heating element in pavements with risk of ice formation, consuming a reasonable amount of energy for both anti-icing (prevention) and deicing (curing), which could turn into an environmentally friendly and cost-effective deicing method. PMID:28773406

  17. In-depth study of cold in-place recycled-pavement performance. Volume 1. Final report. Rept. for Dec 88-Oct 90

    SciTech Connect

    Scholz, T.V.; Hicks, R.G.; Rogge, D.F.

    1990-12-01

    Oregon has developed a mix design procedure for cold in-place recycled (CIR) asphalt concrete pavements. The procedure involves estimation of an initial emulsion content based on gradation of recycled asphalt pavement (RAP), asphalt content of RAP, and penetration and viscosity of recovered asphalt. When an estimated emulsion content is determined, Marshall-sized specimens are prepared for a range of emulsion contents with the range centered on the estimated emulsion content. Hveem and Marshall stability, resilient modulus, and index of retained modulus (IRM) tests are performed on the specimens and a design emulsion content is selected based upon these results. Because of variations in RAP properties, continual need for field adjustments, and the difficulty of interpreting mix property test results, only the estimation part of the procedure is currently implemented. The paper describes the mix design procedure and presents lab results demonstrating the difficulty of choosing emulsion content based on Hveem and Marshall stability, resilient modulus and IRM. Data comparing design emulsion content with actual emulsion contents used in the field are presented. Selection of water content is discussed. Test results of mix properties monitored over time are presented, demonstrating the curing of the emulsion. Performance data for CIR pavements constructed from 1984 through 1988 are presented as well as initial results of an attempt to use lime during recycling to correct a stripped pavement. A construction and inspection manual is presented as a separate document.

  18. In-situ infiltration performance of different permeable pavements in a employee used parking lot--A four-year study.

    PubMed

    Kumar, Kuldip; Kozak, Joseph; Hundal, Lakhwinder; Cox, Albert; Zhang, Heng; Granato, Thomas

    2016-02-01

    Permeable pavements are being adopted as a green solution in many parts of the world to manage urban stormwater quantity and quality. This paper reports on the measured in-situ infiltration performance over a four-year period since construction and use of three permeable parking sections (permeable pavers, permeable concrete and permeable asphalt) of an employee car parking lot. There was only a marginal decline in infiltration rates of all three pavements after one year of use. However, between years two to four, the infiltration rates declined significantly due to clogging of pores either by dry deposition of particles and/or shear stress of vehicles driving and degrading the permeable surfaces; during the last two years, a greater decline was also observed in driving areas of the parking lots compared to parking slots, where minimal wear and tear are expected. Maintenance strategies were employed to reclaim some of the lost infiltration rate of the permeable pavements to limited success. Despite this decline, the infiltration rates were still four to five times higher than average rainstorm intensity in the region. Thus, these permeable pavement parking lots may have significant ecological importance due to their ability to infiltrate rainwater quickly, reduce the runoff in the catchment area, and also dampen runoff peak flows that could otherwise enter the collection system for treatment in a combined sewer area. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Research on steel bridge deck pavement mechanical response of Urumqi express way

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Qian, Z. D.; Xue, Y. C.; Huang, Q. B.

    2017-01-01

    The cold climate of Urumqi influences the pavement performance of steel bridge. Mechanical response and suitable pavement system of Urumqi express way steel bridge deck pavement were studied in this paper. ABAQUS was utilized to build a model of steel bridge deck pavement. Maximum tension stress, maximum tension strain, maximum vertical displacement and maximum inter-laminar shearing stress of “double EA” pavement structure and “lower EA+upper SMA” pavement structure under different pavement thicknesses and different ambient temperatures were calculated. Results indicate that when both the pavement materials of upper layer and lower layer of pavement structure are same, the maximum tension stress, the maximum tension strain, the maximum vertical displacement and the maximum inter-laminar shearing stress of “lower 3cm+upper 4cm” pavement structure are smaller than both “lower 2.5cm+upper 3.5cm” pavement structure and “lower 3cm+upper 3.5cm” pavement structure; at the range of -45°C ~ 70°C, when the pavement materials of upper layer and lower layer of pavement structure is different, the increase of temperature will lead to the decrease of maximum tension stress and maximum inter-laminar shearing stress and will also lead to the increase of the maximum tension strain and the maximum vertical displacement; the maximum tension stress of “double EA” pavement structure is larger than “lower EA+upper SMA” pavement structure; the maximum tension strain, the maximum vertical displacement and the maximum inter-laminar shearing stress of “double EA” pavement structure are close to “lower EA+upper SMA” pavement structure; the “lower 3cm EA+upper 4cm SMA” pavement structure is recommended for the steel bridge deck pavement of Urumqi expressway.

  20. Wavelet-aided pavement distress image processing

    NASA Astrophysics Data System (ADS)

    Zhou, Jian; Huang, Peisen S.; Chiang, Fu-Pen

    2003-11-01

    A wavelet-based pavement distress detection and evaluation method is proposed. This method consists of two main parts, real-time processing for distress detection and offline processing for distress evaluation. The real-time processing part includes wavelet transform, distress detection and isolation, and image compression and noise reduction. When a pavement image is decomposed into different frequency subbands by wavelet transform, the distresses, which are usually irregular in shape, appear as high-amplitude wavelet coefficients in the high-frequency details subbands, while the background appears in the low-frequency approximation subband. Two statistical parameters, high-amplitude wavelet coefficient percentage (HAWCP) and high-frequency energy percentage (HFEP), are established and used as criteria for real-time distress detection and distress image isolation. For compression of isolated distress images, a modified EZW (Embedded Zerotrees of Wavelet coding) is developed, which can simultaneously compress the images and reduce the noise. The compressed data are saved to the hard drive for further analysis and evaluation. The offline processing includes distress classification, distress quantification, and reconstruction of the original image for distress segmentation, distress mapping, and maintenance decision-making. The compressed data are first loaded and decoded to obtain wavelet coefficients. Then Radon transform is then applied and the parameters related to the peaks in the Radon domain are used for distress classification. For distress quantification, a norm is defined that can be used as an index for evaluating the severity and extent of the distress. Compared to visual or manual inspection, the proposed method has the advantages of being objective, high-speed, safe, automated, and applicable to different types of pavements and distresses.

  1. A road pavement full-scale test track containing stabilized bottom ashes.

    PubMed

    Toraldo, E; Saponaro, S

    2015-01-01

    This paper reports the results of a road pavement full-scale test track built by using stabilized bottom ash (SBA) from an Italian municipal solid waste incinerator as the aggregate in granular foundation, cement-bound mixes and asphalt concretes. The investigation focused on both the performance and the environmental compatibility of such mixes, especially with regard to the effects of mixing, laying and compaction. From the road construction point of view, the performance related to the effects of mixing, laying and compaction on constructability was assessed, as well as the volumetric and the mechanical properties. Environmental aspects were investigated by leaching tests. The results suggested that SBA meets the environmental Italian law for the reuse of non-hazardous waste and could be used as road material with the procedures, plants and equipment currently used for road construction.

  2. Tire Footprint Affects Hydroplaning On Wet Pavement

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.

    1989-01-01

    Recent investigations of tire hydroplaning at highway speeds reveal, in addition to inflation pressure, tire-footprint aspect ratio (FAR), defined as width divided by length of tire surface in contact with pavement, significantly influences speed at which dynamic hydroplaning begins. Tire speeds and forces developed during tests of up to 65 mi/h (105 km/h) were monitored on flooded test surface to identify development of hydroplaning. Study focused on automotive tires because FAR's of automotive tires vary more than those of aircraft tires.

  3. Airfield Pavement Construction: Slipform Paving Method

    DTIC Science & Technology

    1975-06-01

    3 4 6 540 Crushed syenite 1-12 -- 5 3 4 -- 520 Crushed limestone 1-12 -- 6 1 4 520 Natural gravel 1-1 4 65 7 -- -- -- Natural gravel 1-1 2 -- 8 12...l6-in.-thick pavement was formed in 25-ft-wide pours. Base Course 39. The base course consisted of 6 in. of cement-treated crushed syenite with...The crushed syenite aggregate had a maximum size of 1-12 in. Paving and Batch Equipment 41. An automatically controlled batch plant was used to batch

  4. Evaluation of western shale-oil residue as an additive to petroleum asphalt for use as a pavement crack and joint sealant material

    SciTech Connect

    Harnsberger, P.M.; Wolf, J.M.; Robertson, R.E.

    1992-11-01

    The objective of this study was to perform a preliminary evaluation of using a distillation residue from Green River Formation (western) shale oil as an additive to a petroleum asphalt for use as a crack and joint filler material in portland cement concrete and asphaltic pavements. A commercially available rubberized asphalt crack and joint filler material was also tested for comparison. ASTM specification tests for sealant materials used in concrete and asphalt pavements were performed on the sealant materials. Portland cement concrete briquets prepared with an asphalt material sandwiched between two concrete wafers were tested in a stress-relaxation experiment to evaluate the relaxation and recovery properties of the sealant materials. The results show that the shale-oil modified petroleum asphalts and the neat petroleum asphalt do not pass the extension portion of the ASTM test; however, there is indication of improvement in the adhesive properties of the shale-oil modified asphalts. There is also evidence that the addition of shale-oil residue to the petroleum asphalt, especially at the 20% level, improves the relaxation and recovery properties compared with the petroleum asphalt.

  5. Potential applicability of stress wave velocity method on pavement base materials as a non-destructive testing technique

    NASA Astrophysics Data System (ADS)

    Mahedi, Masrur

    Aggregates derived from natural sources have been used traditionally as the pavement base materials. But in recent times, the extraction of these natural aggregates has become more labor intensive and costly due to resource depletion and environmental concerns. Thus, the uses of recycled aggregates as the supplementary of natural aggregates are increasing considerably in pavement construction. Use of recycled aggregates such as recycled crushed concrete (RCA) and recycled asphalt pavement (RAP) reduces the rate of natural resource depletion, construction debris and cost. Although recycled aggregates could be used as a viable alternative of conventional base materials, strength characteristics and product variability limit their utility to a great extent. Hence, their applicability is needed to be evaluated extensively based on strength, stiffness and cost factors. But for extensive evaluation, traditionally practiced test methods are proven to be unreasonable in terms of time, cost, reliability and applicability. On the other hand, rapid non-destructive methods have the potential to be less time consuming and inexpensive along with the low variability of test results; therefore improving the reliability of estimated performance of the pavement. In this research work, the experimental program was designed to assess the potential application of stress wave velocity method as a non-destructive test in evaluating recycled base materials. Different combinations of cement treated recycled concrete aggregate (RAP) and recycled crushed concrete (RCA) were used to evaluate the applicability of stress wave velocity method. It was found that, stress wave velocity method is excellent in characterizing the strength and stiffness properties of cement treated base materials. Statistical models, based on P-wave velocity were derived for predicting the modulus of elasticity and compressive strength of different combinations of cement treated RAP, Grade-1 and Grade-2 materials. Two

  6. Evaluation of base widening methods on flexible pavements in Wyoming

    NASA Astrophysics Data System (ADS)

    Offei, Edward

    The surface transportation system forms the biggest infrastructure investment in the United States of which the roadway pavement is an integral part. Maintaining the roadways can involve rehabilitation in the form of widening, which requires a longitudinal joint between the existing and new pavement sections to accommodate wider travel lanes, additional travel lanes or modification to shoulder widths. Several methods are utilized for the joint construction between the existing and new pavement sections including vertical, tapered and stepped joints. The objective of this research is to develop a formal recommendation for the preferred joint construction method that provides the best base layer support for the state of Wyoming. Field collection of Dynamic Cone Penetrometer (DCP) data, Falling Weight Deflectometer (FWD) data, base samples for gradation and moisture content were conducted on 28 existing and 4 newly constructed pavement widening projects. A survey of constructability issues on widening projects as experienced by WYDOT engineers was undertaken. Costs of each joint type were compared as well. Results of the analyses indicate that the tapered joint type showed relatively better pavement strength compared to the vertical joint type and could be the preferred joint construction method. The tapered joint type also showed significant base material savings than the vertical joint type. The vertical joint has an 18% increase in cost compared to the tapered joint. This research is intended to provide information and/or recommendation to state policy makers as to which of the base widening joint techniques (vertical, tapered, stepped) for flexible pavement provides better pavement performance.

  7. Pavement cracking measurements using 3D laser-scan images

    NASA Astrophysics Data System (ADS)

    Ouyang, W.; Xu, B.

    2013-10-01

    Pavement condition surveying is vital for pavement maintenance programs that ensure ride quality and traffic safety. This paper first introduces an automated pavement inspection system which uses a three-dimensional (3D) camera and a structured laser light to acquire dense transverse profiles of a pavement lane surface when it carries a moving vehicle. After the calibration, the 3D system can yield a depth resolution of 0.5 mm and a transverse resolution of 1.56 mm pixel-1 at 1.4 m camera height from the ground. The scanning rate of the camera can be set to its maximum at 5000 lines s-1, allowing the density of scanned profiles to vary with the vehicle's speed. The paper then illustrates the algorithms that utilize 3D information to detect pavement distress, such as transverse, longitudinal and alligator cracking, and presents the field tests on the system's repeatability when scanning a sample pavement in multiple runs at the same vehicle speed, at different vehicle speeds and under different weather conditions. The results show that this dedicated 3D system can capture accurate pavement images that detail surface distress, and obtain consistent crack measurements in repeated tests and under different driving and lighting conditions.

  8. Experimental and Numerical Studies of the Effects of Water Sprinkling on Urban Pavement on Heat Island Mitigation

    NASA Astrophysics Data System (ADS)

    Yoshioka, M.; Tosaka, H.; Nakagawa, K.

    2007-12-01

    One of the main causes of 'heat island phenomeno' is thought to be the artificial covers of the ground surface with asphalt or concrete which reduce greatly inherent cooling effect of water evaporation from soil surface. In this study, as a candidate method of mitigating the heat island the effects of the 'water sprinkling' on the pavements are discussed from field experiments and numerical studies. Three field experiments of water sprinkling on the asphalt/concrete pavements were performed in hot summer days in 2004-2006. For detecting the change in temperatures, the authors developed and used a 3-D measurements system which consists of two vertical planes with 6m high and 16m wide, and has network arrays of 102 thermistors distributed spatially in the planes. The temperatures measured in and around the water sprinkled area indicated that the ground surface temperature decreased 5 to 15 degrees uniformly in the water sprinkled area compared with those in the un-sprinkled area, while the relative decrease of atmospheric temperature was approximately up to 1 degree. The subsurface temperature at a depth of 14cm under the pavement decreased significantly and kept lower than that at the same depth in un-sprinkled area over the next morning. A numerical model was developed and applied to interpret the experimental results. It deals with the heat balance of radiation, sensible/latent heat transfer at the ground surface and heat conduction through the artificial and natural soil layer under ground. temperature and vapor conditions changes at and near ground surface were modeled by using the bulk formula.Good agreements between the calculated time-temperature profiles and the experimental ones were obtained by assuming adequate physical parameters and meteorological conditions. The model could be improved in order to evaluate the changes of temperature and vapor contents in atmosphere near the ground surface caused by aerodynamic turbulent diffusion.

  9. Automated management for pavement inspection system (AMPIS)

    NASA Astrophysics Data System (ADS)

    Chung, Hung Chi; Girardello, Roberto; Soeller, Tony; Shinozuka, Masanobu

    2003-08-01

    An automated in-situ road surface distress surveying and management system, AMPIS, has been developed on the basis of video images within the framework of GIS software. Video image processing techniques are introduced to acquire, process and analyze the road surface images obtained from a moving vehicle. ArcGIS platform is used to integrate the routines of image processing and spatial analysis in handling the full-scale metropolitan highway surface distress detection and data fusion/management. This makes it possible to present user-friendly interfaces in GIS and to provide efficient visualizations of surveyed results not only for the use of transportation engineers to manage road surveying documentations, data acquisition, analysis and management, but also for financial officials to plan maintenance and repair programs and further evaluate the socio-economic impacts of highway degradation and deterioration. A review performed in this study on fundamental principle of Pavement Management System (PMS) and its implementation indicates that the proposed approach of using GIS concept and its tools for PMS application will reshape PMS into a new information technology-based system providing a convenient and efficient pavement inspection and management.

  10. The Plains City Story

    ERIC Educational Resources Information Center

    van Olphen, Marcela; Rios, Francisco; Berube, William; Dexter, Robin; McCarthy, Robert

    2006-01-01

    This case study portrays a contemporary phenomenon that affects many U.S. school districts. Specifically, the authors address the challenges that the superintendent of the Plains City school district faced as a result of a change in the demographic distribution of his district. The gradual development of the pig farming industry in Plains City…

  11. Hummocky and Smooth Plains

    NASA Image and Video Library

    2000-01-15

    This image, from NASA Mariner 10 spacecraft which launched in 1974, is located about 500 km east of the Caloris basin and shows hummocky plains interpreted as Caloris ejecta in the upper half of the picture and smooth plains in the lower half.

  12. Great plains, Chapter 11

    Treesearch

    C.M. Clark

    2011-01-01

    The North American Great Plains are the largest contiguous ecoregion in North America, covering 3.5 million square km2, or 16 percent of the continental area (CEC 1997). In the United States, the Great Plains ecoregion encompasses a roughly triangular region (Figure 2.2), bordered on the west by the Rocky Mountains and the southwestern deserts in...

  13. The Plains City Story

    ERIC Educational Resources Information Center

    van Olphen, Marcela; Rios, Francisco; Berube, William; Dexter, Robin; McCarthy, Robert

    2006-01-01

    This case study portrays a contemporary phenomenon that affects many U.S. school districts. Specifically, the authors address the challenges that the superintendent of the Plains City school district faced as a result of a change in the demographic distribution of his district. The gradual development of the pig farming industry in Plains City…

  14. Evaluation of three state-of-the-art water-jet systems for cutting/removing concrete

    NASA Astrophysics Data System (ADS)

    Pace, C. E.

    1982-09-01

    This report documents a demonstration project to evaluate the capability of three waterjet systems for cutting or removing concrete or both. The Corps of Engineers is interested in the potential of this technology for such applications as rapid cutting of bomb-damaged selection of airfield pavement and removing of deteriorated sections of concrete structures at Civil Works projects. Because water-jet systems are capable of transmitting, without mechanical constraint, all of the available horsepower of their power sources into the concrete cutting/removing operation, they may prove to be an extremely efficient means of conducting such operations. The low-pressure water jets were able to cut a 6-in. slot in the concrete for a distance of 1-1/2 ft. in a period of 24 minutes (a rate of 6.4 ft. per hour). The relatively high-pressure water jet cut at rates of 9.6 ft. per hour for shallow cuts (less than 5 in.) and 3 ft. per hour for deeper cuts (greater than 5 in.). In addition, one of the low-pressure systems was used to remove some surface concrete. The results of this evaluation indicate that, although these water-jet systems did not demonstrate a capability for efficiently cutting concrete airfield pavements, the technology has potential. The low-pressure system demonstrated a capability for removing surface concrete efficiently.

  15. Long-term analysis of slender concrete structures with cracking

    SciTech Connect

    Chern, J.C.; Marchertas, A.H.

    1985-01-01

    A special form of the finite element program, which is based on the equilibrium of forces in various cross sections of the beam together with the principle of virtual work, is presented for solving concrete beam problems. This analytical method uses the newly developed rheological element and exponential algorithm for computing time-dependent deformation and stress distribution in cracked concrete members subjected to sustained loads, temperature, or drying. Temperature and moisture effects on hydration (aging) and creep rate are included. The rate effects of temperature and moisture on the deformation of concrete are also taken into account in the formulation. Numerical examples are used to illustrate the validity of the analysis on concrete beams. Plain and reinforced concrete beams subjected to bending, heating or drying are analyzed and checked against experimental data.

  16. Research on pavement roughness based on the laser triangulation

    NASA Astrophysics Data System (ADS)

    Chen, Wenxue; Ni, Zhibin; Hu, Xinhan; Lu, Xiaofeng

    2016-06-01

    Pavement roughness is one of the most important factors for appraising highway construction. In this paper, we choose the laser triangulation to measure pavement roughness. The principle and configuration of laser triangulation are introduced. Based on this technology, the pavement roughness of a road surface is measured. The measurement results are given in this paper. The measurement range of this system is 50 μm. The measurement error of this technology is analyzed. This technology has an important significance to appraise the quality of highway after completion of the workload.

  17. User’s Guide: Subsurface Drainage for Military Pavements

    DTIC Science & Technology

    1992-08-01

    SUBSURFACE DRAINAGE FOR MILITARY PAVEMENTS DTICSELECTE l S MAY2 51993 by C William P. Grogan US Army Engineer Waterways Experiment Station * Vicksburg, MS...TYPE AND DATES COVERED1 August 1992 I Final report 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS User’s Guide: Subsurface Drainage for Military Pavements 6...Bi ~NrIS C;,A&I [.dlL TAB By 4 1A USER’S GUIDE: SUBSURFACE DRAINAGE FOR MILITARY PAVEMENTS PART I: EXECUTIVE SUMMARY Background Research conducted at

  18. An advanced algorithm for highway pavement fissure detection

    NASA Astrophysics Data System (ADS)

    Chen, Bei; Cao, Wenlun; He, Yuyao

    2012-04-01

    This paper presents image detection method of pavement crack based on fractal dimension feature and designs self-adapting algorithm of fractal dimension interval of pavement region. Through image pretreatment, calculation of fractal dimension, self-adapting calculation of dimension interval, we obtain the location image of damage pavement. The experimental results of transverse crack, longitudinal crack, net-shaped crack, pit slot are contrast with that of Sobel operator. The results show that they have the similar capability on the representation of crack, but the proposed method is more flexible on the aspect of representation of crack size and calculation of damage ratio.

  19. Recycled and virgin plastics in fiber reinforced concrete. Final report, October 1994--August 1997

    SciTech Connect

    Tawfiq, K.S.

    1998-08-30

    The primary objectives of this study is to conduct a laboratory investigation to evaluate the intrinsic stress that can cause cracking of concrete mixed recommended by the Florida Department of Transportation with the addition of monofilament and fibrillated polypropylene and monofilament polyolefin fibers, subjected to highly cyclic loading. In addition, the flexural behavior of concrete reinforced with recycled post-consumer in-house made fibers will be study and Finite Element Methods (FEM) following laboratory work would be used to establish comparable numerical models for the flexural test and pavement overlays.

  20. Early age damage quantification of actively restrained concrete using inverse analysis

    NASA Astrophysics Data System (ADS)

    Albanna, Ali

    Early-age cracking can be a significant problem in concrete pavements, floors, and bridge decks. Cracking occurs when the volumetric changes associated with drying, hydration, and temperature reduction are prevented. Good knowledge about the characteristics of early age concrete is necessary to achieve reliable crack control. Volumetric changes due to shrinkage depend on the type of concrete and its components. It has been found that light weight aggregates can work as internal reservoir to supply the concrete matrix with water that is needed during the early age; this process is called internal curing. Also fibers can give more ductility to the concrete and produce less shrinkage. There is a need to better understand the effects of early age uniaxial restraint on long term concrete mechanical performance. In this study, two types of concrete were studied (high performance fiber reinforced concrete and ordinary concrete) under actively restrained loading conditions to assess the effect on the long term fracture toughness and energy. Single edge notched specimens having dimensions of 250 mm x 150 mm x 75 mm and a notch to depth ratio of 0.33 were caste and used in both direct tension and three point bending. The direct tension tests were carried out on a direct tension loading frame constructed in house that was supplied with two mechanical jacks and load cell.

  1. Research on fracture performance of epoxy asphalt concrete based on double-K fracture criterion

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Qian, Z. D.; Xue, Y. C.

    2017-01-01

    After cracks appear on steel bridge deck epoxy asphalt concrete pavement, cracks propagate fast under vehicle load. This paper studied the fracture performance of epoxy asphalt concrete, utilized single edge notched beam (SEB) three-point bending test, measured the load (P) exerted on epoxy asphalt SEB; utilized digital camera to record the fracture process of epoxy asphalt SEB, extracted the images according to the required sampling frequency and utilized Image-Pro Plus to measure the crack mouth opening displacement (CMOD) of epoxy asphalt SEB on the extracted images; calculated the double-K fracture parameters according to the P-CMOD curve. Results indicate that of epoxy asphalt concrete is 1.11 MPa and of epoxy asphalt concrete is 2.31 MPa at -15°C of epoxy asphalt concrete is 1.02 MPa and of epoxy asphalt concrete is 1.83 MPa at -5°C of epoxy asphalt concrete is 0.77 MPa and of epoxy asphalt concrete is 1.82 MPa at 5°C. The double-K fracture parameters of epoxy asphalt concrete increase slightly when the temperature decreases at the scope of -15°C to 5°C. The relation of and is .

  2. Size-dependent enrichment of waste slag aggregate fragments abraded from asphalt concrete.

    PubMed

    Takahashi, Fumitake; Shimaoka, Takayuki; Gardner, Kevin; Kida, Akiko

    2011-10-30

    Authors consider the environmental prospects of using melted waste slag as the aggregate for asphalt pavement. In particular, the enrichment of slag-derived fragments in fine abrasion dust particles originated from slag asphalt concrete and its size dependency were concerned. A series of surface abrasion tests for asphalt concrete specimens, containing only natural aggregates as reference or 30 wt% of substituted slag aggregates, were performed. Although two of three slag-asphalt concretes generated 1.5-3.0 times larger amount of abrasion dust than the reference asphalt concrete did, it could not be explained only by abrasion resistance of slag. The enrichment of slag-derived fragments in abrasion dust, estimated on the basis of the peak intensity of quartz and heavy metal concentrations, had size dependency for all slag-asphalt concretes. Slag-derived fragments were enriched in abrasion dust particles with diameters of 150-1000 μm. Enrichment factors were 1.4-2.1. In contrast, there was no enrichment in abrasion dust particles with diameter less than 75 μm. This suggests that prior airborne-size fragmentation of substituted slag aggregates does not need to be considered for tested slag aggregates when environmental risks of abrasion dust of slag-asphalt pavement are assessed. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Compressive Strength and Water Absorption of Pervious Concrete that Using the Fragments of Ceramics and Roof Tiles

    NASA Astrophysics Data System (ADS)

    Prahara, E.; Meilani

    2014-03-01

    Pervious concrete was introduced in America in 2003, popularized by Dan Brown and used as a rigid pavement in the open parking lot. Rigid pavement using pervious concrete can absorb water in the surface to go straight through the concrete to the ground below.This water flow is one of the benefit of using the pervious concrete. Using of wastes such as broken roof and ceramics tiles are not commonly used in Indonesia. Utilization these kind of wastes is predicted lower the compressive strength of pervious concrete as they are used as a substitute for coarse aggregate.In this research, pervious concrete is made using a mixture of the fragment of ceramics and roof tiles.This research using broken ceramics and roof tiles with a grain size that loose from 38 mm sieve, retained on 19 mm sieve and the coarse aggregate from crushed stone that loose 12.5 mm sieve, retained on 9.5 mm sieve. The water cement ratio is 0.3 and to assist the mixing process, the addition of addictive in pervious concrete is used.The size of coarse aggregate used in the mixture affects the strength of pervious concrete. The larger the size of aggregate, the obtained compressive strength becomes smaller. It also affects the density of pervious concrete. The using of mixture of ceramics and roof tiles only reduce 2 MPa of pervious concrete compressive strength so this mixture can be used as a substitute for coarse aggregate with a maximum portion of 30 %. The high porosity of the specimens causes the reduction of pervious concrete density that affect the compressive strength. This high level of porosity can be seen from the high level of water absorption that exceed the required limit of water infiltration.

  4. Determination of the Remaining Life of Rigid Airfield Pavement Through Super-Accelerated Pavement Testing

    DTIC Science & Technology

    2004-12-01

    Division of the Texas Department of Transportation (TxDOT), the University of Texas Austin, Department of Civil Engineering , Geotechnical Engineering ...1998, the Geotechnical and Structures Laboratory at the Engineer Research and Development Center (ERDC) located at the USACE WES accepted delivery of...generated by the need for a more comprehensive nondestructive testing method ( NDT ), for pavement evaluations. At the time, a large portion of the

  5. Development of probabilistic rigid pavement design methodologies for military airfields

    NASA Astrophysics Data System (ADS)

    Witczak, M. W.; Uzan, J.; Johnson, M.

    1983-12-01

    The current Corps of Engineers design procedures for rigid airfield pavements is based on the Westergaard free edge stress slab theory, and a proposed procedure is based on the multilayer elastic theory. These two design procedures have been expanded to airfield pavement designs expressed in probabilistic and reliability terms. Further developments were required in these procedures to make the analysis more practicable. Two major investigations were conducted: (1) Evaluation and use of the composite modulus of elasticity for layers beneath the rigid pavement, and (2) Evaluation of the maximum tensile stress at the bottom of the slab for different aircraft types. Derivations obtained from the investigation of the composite modulus and maximum tensile stress are reported and are included in computer programs for probabilistic/reliability analysis of rigid pavements. The approximate closed form (Taylor series expansion) is utilized. Example runs of the computer program are presented.

  6. Striated clast pavements: Products of deforming subglacial sediment?

    NASA Astrophysics Data System (ADS)

    Clark, Peter U.

    1991-05-01

    Studies of modern glaciers have recently drawn attention to the importance of subglacial sediment deformation to glacier dynamics and processes. Inferences regarding the probable shear strength of this sediment imply that large clasts may in some cases sink to underlying rigid sediment, where abrasion by overlying deforming sediment could occur. This scenario provides a formative mechanism for striated clast pavements commonly described from the base of fine-grained massive diamictons associated with the late Pleistocene Laurentide ice sheet. Such a mechanism indicates that, at the time of formation of clast pavements, overlying diamictons associated with pavements had a low yield strength (≤0.5 kPa) and were deforming mechanically like a debris flow. Clast pavements may therefore be an important criterion for recognition of sediments deposited by subglacial deformation transport.

  7. Nondestructive evaluation of load transfer at rigid airport pavement joints

    NASA Astrophysics Data System (ADS)

    Hammons, Michael I.

    1995-07-01

    Current design criteria for rigid pavements for commercial and military airfields assume that 25% of the load applied to an edge of a slab is transferred through the joint to an adjacent unloaded slab. A nondestructive testing technique using a falling weight deflectometer (FWD) was used to conduct field testing at a number of sites. A transfer function, developed from an analytical study, was used to estimate load transfer from the measured joint efficiency as a function of the loaded area and the radius of relative stiffness of the pavement. This procedure, although analytically sound, lacks actual field verification at an instrumented pavement site. This procedure was used to estimate load transfer at a number of commercial and military airfields for a variety of joint types, climate conditions, and pavement structures. The results of these tests indicate that the assumption of load transfer as a constant value of 25% appears to be unconservative, especially during the winter months.

  8. Permeable Pavement Demonstration at the Edison Environmental Center - Poster

    EPA Science Inventory

    Poster for the SAB Review detailing the porous pavement parking lot project. The poster describes the design of the parking lot, the research components that were incorporated into the design, and the monitoring plan.

  9. A HIERARCHICAL HIDDEN MARKOV DETERIORATION MODEL FOR PAVEMENT STRUCTURE

    NASA Astrophysics Data System (ADS)

    Kobayashi, Kiyoshi; Kaito, Kiyoyuki; Eguchi, Toshiyuki; Ohi, Akira; Okizuka, Ryosuke

    The deterioration process of pavement is a complex process including the deterioration of road surface and the decrease in load bearing capacity of the entire pavement. The decrease in load bearing capacity influences the deterioration rate of road surface. The soundness of road surface can be observed by a road surface condition investigation. On the other hand, the decrease in load bearing capacity can be partially observed through the FWD testing, etc. In this study, such a deterioration process of road surface is described as a mixed Markov process that depends on the load bearing capacity of pavement. Then, the complex deterioration process, which is composed of the deterioration of road surface and the decrease in load bearing capacity of pavement, is expressed as a hierarchical hidden Markov deterioration model. Through a case study of the application into the expressway, a hierarchical hidden Markov deterioration model is estimated, and its applicability and effectiveness are empirically discussed.

  10. ANALYSIS OF GROUP MAINTENANCE STRATEGY -ROAD PAVEMENT AND SEWERAGE PIPES-

    NASA Astrophysics Data System (ADS)

    Tanimoto, Keishi; Sugimoto, Yasuaki; Miyamoto, Shinya; Nada, Hideki; Hosoi, Yoshihiko

    Recently, it is critical to manage deteriorating sewerage and road facilities efficiently and strategically. Since the sewerage pipes are mostly installed under road pavement, the works for the replacement of the sewerage pipes are partially common to the works for the road. This means that the replacement cost can be saved by coordinating the timing of the replacements by sewerage pipe and road pavement. The purpose of the study is to develop the model based on Markov decision process to derive the optimal group maintenance policy so as to minimize lifecycle cost. Then the model is applied to case study area and demonstrated to estimate the lifecycle cost using statistical data such as pipe replacement cost, road pavement rehabilitation cost, and state of deterioration of pipes and road pavement.

  11. Compressive strength of dune sand reinforced concrete

    NASA Astrophysics Data System (ADS)

    Mohammed, Mani; Abdelouahed, Kriker; Allaoua, Belferrag

    2017-02-01

    Many areas of south Algeria suffer from the problem of accumulation of sand on constructions. In fact, the phenomenon of sand silting causes technical and economical problems. Besides, these areas and other regions in Algeria suffer from the problem of unavailability of suitable sand for building. The use of dune sand offers an alternative solution for construction. In the same context, many researches confirm the possibility of using dune sand in the composition of concrete. In this paper, concrete made with dune sand was studied. For correction of the granulometry of dune sand by river sand, the rates of 50% DS+50% RS and 40% DS+60% RS were used. Also, two types of fibers were used, with 45 and 30 mm lengths, and diameters of 1 and 0.5 mm respectively. The percentage of the used fibers in the sand concrete was 1% and 1.5%. In this work an improvement of the compressive strength for the metal fibers reinforced sand concrete compared to plain concrete was obtained.

  12. Joint Sealants for Airport Pavements. Phase 1. Laboratory Field Investigations

    DTIC Science & Technology

    1988-12-01

    Highway Research Board. Special Report 112: "Joint Sealing: A Glossary," Washington, DC, 1970. 9. D.A. Peterson. " Resealing Joints and Cracks in Rigid ...and Flexible Pavements," NCHRP-SHP 98, Transportation Research Board, Washington, DC, Dec 1982. 10. J.W. Bugler. " Rigid Pavement Joint Resealing : Field...tests. Special thanks to the following for their assistance and input during the airport site surveys: Atlanta Hartsfield International Mr. Mike Pack

  13. Understanding the Effects of Climate on Airfield Pavement Deterioration Rates

    DTIC Science & Technology

    2013-03-01

    Objectives The objective of this research was to answer the question: How can climate regions, within the United States, be used to understand and...of pavement deterioration. In flexible pavements, high and low temperatures can affect the stiffness properties of the bituminous layers. For...example, at low or freezing temperatures, asphalt becomes hard and brittle, which can cause thermal cracking (Hironaka, Cline, & Schiavino, 2004). In

  14. Performance of Cracked and Seated Rigid Airport Pavements.

    DTIC Science & Technology

    1987-04-01

    Transportation Final Report Federal Aviation Administration 800 Independence Avenue, S.W. Sa . g c¢e Washington, D.C. 20591 APM-740 15. Supplementary Notes...Gear ........................ 51 9 FAA Flexible Pavement Desgin Curves - Dual Wheel Gear .......................... 52 10 FAA Flexible Pavement Design...properly address (cure and prevent future occurrences) the problem, and (3) select the optimal rehabilitation method based upon economic and other non

  15. Environmental assessment of pavement infrastructure: A systematic review.

    PubMed

    Inyim, Peeraya; Pereyra, Jose; Bienvenu, Michael; Mostafavi, Ali

    2016-07-01

    Through a critical review and systematic analysis of pavement life cycle assessment (LCA) studies published over the past two decades, this study shows that the available information regarding the environmental impacts of pavement infrastructure is not sufficient to determine what pavement type is more environmentally sustainable. Limitations and uncertainties related to data, system boundary and functional unit definitions, consideration of use and maintenance phase impacts, are identified as the main reasons for inconsistency of reported results in pavement LCA studies. The study outcomes also highlight the need for advancement of knowledge pertaining to: (1) utilization of performance-adjusted functional units, (2) accurate estimation of use, maintenance, and end-of-life impacts, (3) incorporation of the dynamic and uncertain nature of pavement condition performance in impact assessment; (4) development of region-specific inventory data for impact estimation; and (5) consideration of a standard set of impact categories for comparison of environmental performance of different pavement types. Advancing the knowledge in these areas is critical in providing consistent and reliable results to inform decision-making toward more sustainable roadway infrastructure.

  16. Urban pavement surface temperature. Comparison of numerical and statistical approach

    NASA Astrophysics Data System (ADS)

    Marchetti, Mario; Khalifa, Abderrahmen; Bues, Michel; Bouilloud, Ludovic; Martin, Eric; Chancibaut, Katia

    2015-04-01

    The forecast of pavement surface temperature is very specific in the context of urban winter maintenance. to manage snow plowing and salting of roads. Such forecast mainly relies on numerical models based on a description of the energy balance between the atmosphere, the buildings and the pavement, with a canyon configuration. Nevertheless, there is a specific need in the physical description and the numerical implementation of the traffic in the energy flux balance. This traffic was originally considered as a constant. Many changes were performed in a numerical model to describe as accurately as possible the traffic effects on this urban energy balance, such as tires friction, pavement-air exchange coefficient, and infrared flux neat balance. Some experiments based on infrared thermography and radiometry were then conducted to quantify the effect fo traffic on urban pavement surface. Based on meteorological data, corresponding pavement temperature forecast were calculated and were compared with fiels measurements. Results indicated a good agreement between the forecast from the numerical model based on this energy balance approach. A complementary forecast approach based on principal component analysis (PCA) and partial least-square regression (PLS) was also developed, with data from thermal mapping usng infrared radiometry. The forecast of pavement surface temperature with air temperature was obtained in the specific case of urban configurtation, and considering traffic into measurements used for the statistical analysis. A comparison between results from the numerical model based on energy balance, and PCA/PLS was then conducted, indicating the advantages and limits of each approach.

  17. Influence of pavement condition on horizontal curve safety.

    PubMed

    Buddhavarapu, Prasad; Banerjee, Ambarish; Prozzi, Jorge A

    2013-03-01

    Crash statistics suggest that horizontal curves are the most vulnerable sites for crash occurrence. These crashes are often severe and many involve at least some level of injury due to the nature of the collisions. Ensuring the desired pavement surface condition is one potentially effective strategy to reduce the occurrence of severe accidents on horizontal curves. This study sought to develop crash injury severity models by integrating crash and pavement surface condition databases. It focuses on developing a causal relationship between pavement condition indices and severity level of crashes occurring on two-lane horizontal curves in Texas. In addition, it examines the suitability of the existing Skid Index for safety maintenance of two-lane curves. Significant correlation is evident between pavement condition and crash injury severity on two-lane undivided horizontal curves in Texas. Probability of a crash becoming fatal is appreciably sensitive to certain pavement indices. Data suggested that road facilities providing a smoother and more comfortable ride are vulnerable to severe crashes on horizontal curves. In addition, the study found that longitudinal skid measurement barely correlates with injury severity of crashes occurring on curved portions. The study recommends exploring the option of incorporating lateral friction measurement into Pavement Management System (PMS) databases specifically at curved road segments.

  18. Relating pavement distress to serviceability and performance

    NASA Astrophysics Data System (ADS)

    Hudson, W. R.; Finn, F. N.; Pedigo, R. D.; Roberts, F. L.

    1981-02-01

    Regression analyses, Markov processes, Bayesian analysis, and utility theory were examined as analytical tools useful in relating distress to performance. Several specific performance models of limited applicability are reported, along with some generally applicable techniques and recommended methods. It is shown that useful relationships can be obtained from existing data and are, in fact, being used in several states and other highway agencies. In each case, however, it is shown that significant improvements in the distress performance relationships are needed which can only be obtained through the conscientious observation of distress and performance of pavements under a variety of environmental and load conditions for a reasonable period of time, e.g., (approximately ten years).

  19. 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%.

  20. Triton Volcanic Plains

    NASA Image and Video Library

    2009-08-25

    This view of the volcanic plains of Neptune moon Triton was produced using topographic maps derived from images acquired by NASA Voyager spacecraft during its August 1989 flyby, 20 years ago this week.

  1. Triton Volcanic Plains #2

    NASA Image and Video Library

    2009-08-25

    This view of the volcanic plains of Neptune moon Triton was produced using topographic maps derived from images acquired by NASA Voyager spacecraft during its August 1989 flyby, 20 years ago this week.

  2. Impact echo scanning of concrete and wood

    NASA Astrophysics Data System (ADS)

    Sack, Dennis A.; Olson, Larry D.; Aouad, Marwan F.

    1995-05-01

    This paper presents an overview of a new nondestructive testing (NDT) system that allows rapid nondestructive assessment of many types of structural materials. The new system is based on scanning impact echo (IE), using a rolling receiver, digitally controlled impact source, and a distance measurement wheel integrated into a system that is capable of performing over 3000 IE tests per hour. The system has been successfully used on both concrete and wood for condition assessment. Previously, impact echo testing has been limited to point-by-point testing at rates of typically 30 - 60 points per hour. The new system is usable on any flat, relatively smooth surface such as floor slabs, pavements, walls, columns, beams, etc. In addition to IE scanning, the new system has recently been expanded to allow the performance of spectral analysis of surface waves (SASW) scanning on concrete and wood. The SASW method allows the measurement of material stiffness (modulus) versus depth, and therefore can give a profile of the material condition versus depth. Included in this paper are brief discussions of the IE and SASW methods, the scanner system hardware, and the software which was developed to enable efficient processing, analysis, and display of the test data and results. Also included are sample data plots and a case history presentation of the use of the system in the field, including one in which 23,000 IE tests were performed on an elevated floor slab in approximately 16 hours of testing time.

  3. Behavior of concrete cylinders confined by carbon-composite tapes and prestressed yarns 1. Experimental data

    NASA Astrophysics Data System (ADS)

    Tamuzs, V.; Tepfers, R.; You, Chi-Sang; Rousakis, T.; Repelis, I.; Skruls, V.; Vilks, U.

    2006-01-01

    The results of a comprehensive test program for the mechanical behavior of round concrete specimens confined by carbon-fiber epoxy tapes and prestressed carbon yarns are reported. Five different concrete batches of compressive strength from 20 to 100 MPa and the confinement of various thickness and pretension level were investigated. The specimens, which were subjected to monotonic or repeated compressive loadings, showed a nonlinear stress-strain behavior with a significant ductility and increased ultimate strength, in contrary to the brittle behavior of plain concrete. The limit of linearity on the stress-strain diagrams of the confined concrete roughly coincided with the ultimate strength of plain concrete. Above this limit, the damage accumulation and plastic deformations proceeded in the confined specimens. This fact was evidenced by the increasing slope of deformation diagrams in unloadings and repeated loadings and by the pronounced residual strains. The limit of linearity could be raised significantly by pretension of the carbon yarns during their winding.

  4. Field investigation of low-temperature cracking and stiffness moduli on selected roads with conventional and high modulus asphalt concrete

    NASA Astrophysics Data System (ADS)

    Judycki, Józef; Jaczewski, Mariusz; Ryś, Dawid; Pszczoła, Marek; Jaskuła, Piotr; Glinicki, Adam

    2017-09-01

    High Modulus Asphalt Concrete (HMAC) was introduced in Poland as a one of the solutions to the problem of rutting, type of deterioration common in the 1990s. After first encouraging trials in 2002 HMAC was widely used for heavily loaded national roads and motorways. However some concerns were raised about low-temperature cracking of HMAC. This was the main reason of the studies presented in this article were started. The article presents the comparison of performance of pavements constructed in typical contract conditions with the road bases made of HMAC and conventional asphalt concrete (AC). The field investigation was focused on the number of low-temperature cracks, bearing capacity (based on FWD test) of road sections localized in coldest region of Poland. Also load transfer efficiency of selected low-temperature cracks was assessed. FWD test confirmed lower deflections of pavements with HMAC and two times higher stiffness modulus of asphalt courses in comparison to pavements constructed with conventional AC mixtures. Relation of stiffness of asphalt layers and amount of low-temperature cracks showed that the higher stiffness modulus of asphalt layers could lead to increase of the number of low-temperature cracks. FWD test results showed that the load transfer efficiency of low-temperature cracks on pavements with HMAC presents very low values, very close to lack of load transfer. It was surprising as section with HMAC road base were aged from 2 to 5 years and presented very good bearing capacity.

  5. Lunar concrete for construction

    NASA Technical Reports Server (NTRS)

    Cullingford, Hatice S.; Keller, M. Dean

    1992-01-01

    Feasibility of using concrete for lunar base construction was discussed recently without relevant data for the effects of vacuum on concrete. Our experimental studies performed earlier at Los Alamos have shown that concrete is stable in vacuum with no deterioration of its quality as measured by the compressive strength. Various considerations of using concrete successfully on the Moon are provided in this paper, along with specific conclusions from the existing database.

  6. Lunar concrete for construction

    NASA Technical Reports Server (NTRS)

    Cullingford, Hatice S.; Keller, M. Dean

    1988-01-01

    Feasibility of using concrete for lunar-base construction has been discussed recently without relevant data for the effects of vacuum on concrete. Experimental studies performed earlier at Los Alamos have shown that concrete is stable in vacuum with no deterioration of its quality as measured by the compressive strength. Various considerations of using concrete successfully on the moon are provided in this paper along with specific conclusions from the existing data base.

  7. Lunar concrete for construction

    SciTech Connect

    Cullingford, H.S.; Keller, M.D.

    1988-01-01

    Feasibility of using concrete for lunar-base construction has been discussed recently without relevant data for the effects of vacuum on concrete. Our experimental studies performed earlier at Los Alamos have shown that concrete is stable in vacuum with no deterioration of its quality as measured by the compressive strength. Various considerations of using concrete successfully on the moon are provided in this paper along with specific conclusions from the existing data base. 10 refs., 3 figs., 2 tabs.

  8. Properties of Sulfur Concrete.

    DTIC Science & Technology

    1979-07-06

    This report summarizes the state of the art of sulfur concrete . Sulfur concrete is created by mixing molten sulfur with aggregate and allowing the...and many organic compounds. It works well as a rapid runway repair material. Sulfur concrete also has unfavorable properties. It has poor durability

  9. Development of Advanced Constitutive Models for Plain and Reinforced Concrete.

    DTIC Science & Technology

    1987-03-01

    gravity. The test specimen rests as shown on an anvil. which is usually fabricated from a high strength steel and remains elastic during the impact...glissement et le calcul des deplacements dans la deformation plastique ." Comptes rendus de lAcademie des Sciences, 225 (1947). 1272. 4. Spencer. A. J. M

  10. The Plains of Venus

    NASA Astrophysics Data System (ADS)

    Sharpton, V. L.

    2013-12-01

    Volcanic plains units of various types comprise at least 80% of the surface of Venus. Though devoid of topographic splendor and, therefore often overlooked, these plains units house a spectacular array of volcanic, tectonic, and impact features. Here I propose that the plains hold the keys to understanding the resurfacing history of Venus and resolving the global stratigraphy debate. The quasi-random distribution of impact craters and the small number that have been conspicuously modified from the outside by plains-forming volcanism have led some to propose that Venus was catastrophically resurfaced around 725×375 Ma with little volcanism since. Challenges, however, hinge on interpretations of certain morphological characteristics of impact craters: For instance, Venusian impact craters exhibit either radar dark (smooth) floor deposits or bright, blocky floors. Bright floor craters (BFC) are typically 100-400 m deeper than dark floor craters (DFC). Furthermore, all 58 impact craters with ephemeral bright ejecta rays and/or distal parabolic ejecta patterns have bright floor deposits. This suggests that BFCs are younger, on average, than DFCs. These observations suggest that DFCs could be partially filled with lava during plains emplacement and, therefore, are not strictly younger than the plains units as widely held. Because the DFC group comprises ~80% of the total crater population on Venus the recalculated emplacement age of the plains would be ~145 Ma if DFCs are indeed volcanically modified during plains formation. Improved image and topographic data are required to measure stratigraphic and morphometric relationships and resolve this issue. Plains units are also home to an abundant and diverse set of volcanic features including steep-sided domes, shield fields, isolated volcanoes, collapse features and lava channels, some of which extend for 1000s of kilometers. The inferred viscosity range of plains-forming lavas, therefore, is immense, ranging from the

  11. Post-Glacial Ant Generated Desert Pavements in Southeastern Oregon

    NASA Astrophysics Data System (ADS)

    Leonard, K. C.

    2001-12-01

    Desert pavements typically require thousands to tens of thousands of years to reach a high level of development. In a pluvial lake valley in Southeastern Oregon I have observed harvester ants creating desert pavement-like features in less than two months. The summer lake basin is a fairly simple sedimentary system. In the eastern half of the basin, the basaltic bedrock is buried under tens of meters of alluvial deposits which lie beneath an approximately ten meter thick dune sheet. The dune sands are noticably different in grainsize and chemistry than the fine component of the alluvial deposits. The dunes began to form at the end of the last pluvial interval (Allison 1980) and continue to be active today. Roughly one fourth of the total area of the dune sheet is mantled with desert pavement, consisting of very coarse sand and fine pebbles (1-8 mm diameter). The dune sand is very fine grained with a considerable amount of silt and minimal clay. It forms thin (2-20 cm thick) well developed Av horizons beneath the desert pavement. Owyhee harvester ants (Pogonomyrmex owyheei) in the area use pebbles of the same size and petrology as the desert pavements to construct their hills. For the ants the closest source of these pebbles is often the alluvium, ten meters below the anthill, rather than in a desert pavement deposit at some distance away overland. An experiment conducted between June and August 1999 demonstrated that the ants rebuild their hills with newly excavated pebbles. When the colonies die off after 5-25 years, the pebbles are stranded at the surface. Processes such as those described by Haff and Werner (1996), where jackrabbits and birds were observed kicking desert pavement clasts aross the ground serve to redistribute the pebbles across the surface of the sand dunes. The sand dunes have been forming over an 8000 year period. Based on anthill-regrowth measurements, the lifespan of an individual colony of harvester ants leads to the excavation of only enough

  12. Evaluation of Three Porous Pavement Systems in a Newly Constructed Parking Lot

    EPA Science Inventory

    This project examines porous pavement systems in a newly constructed parking lot next to Building 205 at the Edison Environmental Center. Porous pavement systems are one means of promoting environmental sustainability through stormwater runoff reduction. This project examines t...

  13. Influence of Cracks on the Lifetime of Semi-Rigid Pavements

    NASA Astrophysics Data System (ADS)

    Kazimierowicz-Frankowska, Krystyna

    2016-12-01

    This paper focuses on a better understanding of the process of reflective cracking propagation through the pavement structure. A series of finite element numerical simulations were conducted to investigate the initial stress and strain states in typical semi-rigid pavements with and without reflective cracks under traffic loading. It was assumed that reflective-cracks propagate from the base layer to the pavement surface. The influence of selected parameters, such as the load position, overlay thickness, and subgrade quality on stress and strain concentrations was investigated. The behaviour of the pavement structure under repeated traffic loading was analyzed in terms of ground compaction. The original theoretical model proposed by Prof. Andrzej Sawicki was used to predict the deformation of a pavement subgrade subjected to traffic loading. The damaging effect of cracks appearing in the pavement structure was investigated. It was found that even a single crack in the pavement structure may significantly reduce the pavement lifetime.

  14. Evaluation of Three Porous Pavement Systems in a Newly Constructed Parking Lot

    EPA Science Inventory

    This project examines porous pavement systems in a newly constructed parking lot next to Building 205 at the Edison Environmental Center. Porous pavement systems are one means of promoting environmental sustainability through stormwater runoff reduction. This project examines t...

  15. STUDY ON FLOOD CONTROL PROPERTIES OF PERMEABLE PAVEMENT USING SATURATED-UNSATURATED SEEPAGE ANALYSIS

    NASA Astrophysics Data System (ADS)

    Yano, Takao; Nishiyama, Satoshi; Ohnishi, Yuzo; Nakashima, Shinichiro; Moriishi, Kazushi; Wada, Minoru

    The rainfall storage and infiltration facility of permeable pavement have been attracted attention as a control measure of flood and an environmental improvement measure in urban areas. However, rainfall infiltration of permeable pavement is unsteady flow and strongly dependent on the behavior of unsaturated zones in the pavement. Moreover, the wet condition of subbase course also has a great influence on the rainfall infiltration of the pavement. That's why previous studies have not made clear the precise the facility of permeable pavement as a flood control. In this paper, experimental studies and simulated analyses were performed to measure the overflow from the pavement under various conditions of rainfall intensities and estimate the rainfall infiltration of the pavement using the measurement data and unsaturated infiltration characteristics of porous asphalt materials. It is clear that this study shows the methods to have a quantitative estimation of the rainfall storage and infiltration facility of permeable pavement.

  16. Use of Nano-SiO2 to Improve Microstructure and Compressive Strength of Recycled Aggregate Concretes

    NASA Astrophysics Data System (ADS)

    Hosseini, P.; Booshehrian, A.; Delkash, M.; Ghavami, S.; Zanjani, M. K.

    The purpose of this paper is to provide new type of recycled aggregate concrete (RAC) incorporating nano-SiO2. In particular, we investigate the effects of colloidal nano-silica solution on the properties of fresh and hardened concrete. The main variables included the dosage of nano-silica (including 0%, 1.5%, and 3% of cement content) and the cement content of the concrete (including 400 and 450 kg/m3). Results were compared with plain concretes. Tests were conducted to determine the mechanical properties (compressive strength) and microstructure (SEM test) of the concretes.

  17. Ice melting properties of steel slag asphalt concrete with microwave heating

    NASA Astrophysics Data System (ADS)

    Li, Bin; Sun, Yihan; Liu, Quantao; Fang, Hao; Wu, Shaopeng; Tang, Jin; Ye, Qunshan

    2017-03-01

    The ice on the surface of asphalt pavement in winter significantly influences the road transportation safety. This paper aims at the improvement of the ice melting efficiency on the surface of asphalt pavement. The steel slag asphalt concrete was prepared and the high ice melting efficiency was achieved with the microwave heating. A series of experiments were conducted to evaluate the ice melting performance of steel slag asphalt concrete, including the heating test, ice melting test, thermal conductivity test and so on. The results indicated that the microwave heating of steel slag concrete can improve the efficiency of deicing, mainly because the heating rates of steel slag asphalt mixture are much better than traditional limestone asphalt mixture. According to different thickness lever of ice, the final temperatures of each sample were very close to each other at the end of melting test. It is believed the thickness of the ice has a limited impact on the ice melting efficiency. According to the heating tests results, the bonding of ice and asphalt concrete is defined failure at the moment when the surface temperature of the ice reached 3 °C.

  18. Design, Construction and Performance of Resin Modified Pavement at Fort Campbell Army Airfield, Kentucky

    DTIC Science & Technology

    1994-03-01

    similar to a PCC pavement that had been treated with muriatic acid . The shot blasting took approximately 3 days and cost $16,000. The unit cost was $2.75...October 1992. 14. SUBJECT TERMS 15. NUMBER OF PAGES Airfield pavement Open-graded asphalt 66 Cement grout Resin-modified pavement 16. PRICE CODE Fuel

  19. 23 CFR 973.208 - Indian lands pavement management system (PMS).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... rehabilitation strategies for pavements using life cycle cost analysis or a comparable procedure; (D) Performs... 23 Highways 1 2011-04-01 2011-04-01 false Indian lands pavement management system (PMS). 973.208... PROGRAM Bureau of Indian Affairs Management Systems § 973.208 Indian lands pavement management system (PMS...

  20. Development of ground-penetrating radar equipment for detecting pavement condition for preventive maintenance

    NASA Astrophysics Data System (ADS)

    Smith, S. S.; Scuillion, T.

    1993-10-01

    The report documents the development of a ground penetrating radar (GPR) system for locating potential maintenance problems in highway pavements. The report illustrates how GPR has the potential to detect four defects in pavements: stripping in an asphalt layer; moisture in base layer; voids or loss of support under rigid pavements; and overlay delamination.

  1. 76 FR 67018 - Notice to Manufacturers of Airport In-Pavement Stationary Runway Weather Information Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-28

    ... Federal Aviation Administration Notice to Manufacturers of Airport In-Pavement Stationary Runway Weather... of In-Pavement Stationary Runway Weather Information Systems. SUMMARY: Projects funded under the... Active or Passive In- Pavement Stationary Runway Weather Information Systems that meet the requirements...

  2. Mountains, Craters and Plains

    NASA Image and Video Library

    2016-03-17

    New Horizons views of the informally named Sputnik Planum on Pluto (top) and the informally named Vulcan Planum on Charon (bottom). Both scale bars measure 20 miles (32 kilometers) long; illumination is from the left in both instances. The Sputnik Planum view is centered at 11°N, 180°E, and covers the bright, icy, geologically cellular plains. Here, the cells are defined by a network of interconnected troughs that crisscross these nitrogen-ice plains. At right, in the upper image, the cellular plains yield to pitted plains of southern Sputnik Planum. This observation was obtained by the Ralph/Multispectral Visible Imaging Camera (MVIC) at a resolution of 1,050 feet (320 meters) per pixel. The Vulcan Planum view in the bottom panel is centered at 4°S, 4°E, and includes the "moated mountain" Clarke Mons just above the center of the image. As well as featuring impact craters and sinuous troughs, the water ice-rich plains display a range of surface textures, from smooth and grooved at left, to pitted and hummocky at right. This observation was obtained by the Long Range Reconnaissance Imager (LORRI) at a resolution of 525 feet (160 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20535

  3. Cementitious porous pavement in stormwater quality control: pH and alkalinity elevation.

    PubMed

    Kuang, Xuheng; Sansalone, John

    2011-01-01

    A certain level of alkalinity acts as a buffer and maintains the pH value in a stable range in water bodies. With rapid urban development, more and more acidic pollutants flow to watersheds with runoff and drop alkalinity to a very low level and ultimately degrade the water environment. Cementitious porous pavement is an effective tool for stormwater acidic neutralization. When stormwater infiltrates cement porous pavement (CPP) materials, alkalinity and pH will be elevated due to the basic characteristics of cement concrete. The elevated alkalinity will neutralize acids in water bodies and maintain the pH in a stable level as a buffer. It is expected that CPP materials still have a certain capability of alkalinity elevation after years of service, which is important for CPP as an effective tool for stormwater management. However, few previous studies have reported on how CPP structures would elevate runoff alkalinity and pH after being exposed to rainfall-runoff for years. In this study, three groups of CPP specimens, all exposed to rainfall-runoff for 3 years, were used to test the pH and alkalinity elevation properties. It was found that runoff pH values were elevated from 7.4 to the range of 7.8-8.6 after infiltrating through the uncoated specimens, and from 7.4 to 8.5-10.7 after infiltrating through aluminum-coated specimens. Runoff alkalinity elevation efficiencies are 11.5-14.5% for uncoated specimens and 42.2% for coated specimens. The study shows that CPP is an effective passive unit operation for stormwater acid neutralization in our built environment.

  4. Pavement Subsidence in the Cumberland Gap Tunnel, USA: A Story of Groundwater Chemistry

    NASA Astrophysics Data System (ADS)

    Zhu, J.; Currens, J. C.; Webb, S. E.; Rister, B. W.

    2014-12-01

    Cumberland Gap Tunnel was constructed in 1996 to improve highway travel between southeastern Kentucky and northeastern Tennessee and to restore Cumberland Gap to its historical appearance. About five years after construction, the concrete pavement in the tunnel began to exhibit noticeable signs of subsidence. Ground penetrating radar surveys detected voids in many areas of the limestone roadbed aggregate beneath the pavement. Field investigations conducted by the Kentucky Geological Survey and Kentucky Transportation Center from 2006 to 2008 discovered that groundwater was flowing from the bedrock invert into the aggregate along many parts of the tunnel. Average groundwater discharge from the tunnel was measured at approximately 1700 m3/d. We analyzed 265 groundwater samples collected from aggregate in different parts of the tunnel roadbed during low and high flow conditions. Calculated calcite saturation indices indicated that the groundwater was geochemically aggressive and capable of continuously dissolving calcite in the limestone aggregate although pH values of these water samples were near neutral. We also conducted an in-situ dissolution experiment by placing eight baskets filled with limestone aggregate beneath the roadbed in different locations in the tunnel for 178 days. At the end of the experiment, the limestone aggregate in contact with groundwater exhibited visual signs of dissolution and lost mass, and the highest mass loss recorded was 3.4 percent. Mass loss calculations based on kinetic models of calcite mineral and water samples taken near the baskets matched well with the actual measured mass losses, confirming that dissolution of calcite by the groundwater was the primary cause of the roadbed subsidence problem. Based on these findings, we suggested the limestone aggregate be replaced with noncarbonate (granite) aggregate to mitigate future road subsidence. The suggestion was adopted, and the repair was completed in early 2014.

  5. Urban evaporation rates for water-permeable pavements.

    PubMed

    Starke, P; Göbel, P; Coldewey, W G

    2010-01-01

    In urban areas the natural water balance is disturbed. Infiltration and evaporation are reduced, resulting in a high surface runoff and a typical city climate, which can lead to floods and damages. Water-permeable pavements have a high infiltration rate that reduces surface runoff by increasing the groundwater recharge. The high water retention capacity of the street body of up to 51 l/m(2) and its connection via pores to the surface lead to higher evaporation rates than impermeable surfaces. A comparison of these two kinds of pavements shows a 16% increase in evaporation levels of water-permeable pavements. Furthermore, the evaporation from impermeable pavements is linked directly to rain events due to fast-drying surfaces. Water-permeable pavements show a more evenly distributed evaporation after a rain event. Cooling effects by evaporative heat loss can improve the city climate even several days after rain events. On a large scale use, uncomfortable weather like sultriness or dry heat can be prevented and the urban water balance can be attenuated towards the natural.

  6. 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.

  7. Nondestructive pavement evaluation technique using falling weight deflectometer

    SciTech Connect

    Al-Nageim, H.; Al-Hakim, B.; Lesley, L.

    1996-11-01

    An analytical method to predict the mechanical properties of a multi-layer pavement structure is presented. The development of the model is based on a modified back calculation model, using a finite circular plate resting on an elastic layered system. The deflection of the pavement under the dynamic action of the falling weight deflectometer (FWD) is taken as a function of the load action and the characteristic strength of the layers comprising the system including the friction between the individual layers. The responses of the pavement during the impact loading of the falling weight are measured and analyzed to predict the stress, strain and coefficient of friction between the layers making the system. The results revealed that the model which incorporates the interface of friction coefficient in the back-analysis technique allows for a more accurate calculation of the mechanical properties of the pavements and thus can be used as a quality control to assess the state of adhesion between the pavement layer system.

  8. Experimental Study on Color Durability of Color Asphalt Pavement

    NASA Astrophysics Data System (ADS)

    Ning, Shi; Huan, Su

    2017-06-01

    Aiming at the poor Color durability and the lack of research on Color asphalt pavement, spraying an anti-tire trace seal resin emulsion on the surface, a Color durable asphalt pavement was proposed. After long-term rolling and long-term aging test, the Color durability was evaluated by RGB function in Photoshop and trace residue rate formula. Test results proved that the Evaluation method was simple and effective. After long-term rolling, the Color of the road surface tends to a constant value. Spraying the emulsion on the road surface can resist tire traces. After long-term aging test, the resistance to tire traces was increased by 26.6% compared with the conventional type, while the former was 44.1% higher than the latter without long-term aging. The Color durable asphalt pavement can effectively improve the ability of Color asphalt pavement to resist tire traces, and significantly improve the Color durability of Color asphalt pavement.

  9. Nuclear waste package fabricated from concrete

    SciTech Connect

    Pfeiffer, P.A.; Kennedy, J.M.

    1987-03-01

    After the United States enacted the Nuclear Waste Policy Act in 1983, the Department of Energy must design, site, build and operate permanent geologic repositories for high-level nuclear waste. The Department of Energy has recently selected three sites, one being the Hanford Site in the state of Washington. At this particular site, the repository will be located in basalt at a depth of approximately 3000 feet deep. The main concern of this site, is contamination of the groundwater by release of radionuclides from the waste package. The waste package basically has three components: the containment barrier (metal or concrete container, in this study concrete will be considered), the waste form, and other materials (such as packing material, emplacement hole liners, etc.). The containment barriers are the primary waste container structural materials and are intended to provide containment of the nuclear waste up to a thousand years after emplacement. After the containment barriers are breached by groundwater, the packing material (expanding sodium bentonite clay) is expected to provide the primary control of release of radionuclide into the immediate repository environment. The loading conditions on the concrete container (from emplacement to approximately 1000 years), will be twofold; (1) internal heat of the high-level waste which could be up to 400/sup 0/C; (2) external hydrostatic pressure up to 1300 psi after the seepage of groundwater has occurred in the emplacement tunnel. A suggested container is a hollow plain concrete cylinder with both ends capped. 7 refs.

  10. Northern Plains 'Crater'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    10 December 2004 The lower left (southwest) corner of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the location of a somewhat filled and buried meteor impact crater on the northern plains of Mars. The dark dots are boulders. A portion of a similar feature is seen in the upper right (northeast) corner of the image. This picture, showing landforms (including the odd mound north/northeast of the crater) that are typical of the martian northern lowland plains, was obtained as part of the MGS MOC effort to support the search for a landing site for the Phoenix Mars Scout lander. Phoenix will launch in 2007 and land on the northern plains in 2008. This image is located near 68.0oN, 227.4oW, and covers an area approximately 3 km (1.9 mi) wide. The scene is illuminated by sunlight from the lower left.

  11. COST Action TU1208 - Working Group 2 - GPR surveying of pavements, bridges, tunnels and buildings; underground utility and void sensing

    NASA Astrophysics Data System (ADS)

    Pajewski, Lara; Benedetto, Andrea; Derobert, Xavier; Fontul, Simona; Govedarica, Miro; Gregoire, Colette; Loizos, Andreas; Perez-Gracia, Vega; Plati, Christina; Ristic, Aleksandar; Tosti, Fabio; Van Geem, Carl

    2017-04-01

    This work aims at presenting the main results achieved by Working Group (WG) 2 "GPR surveying of pavements, bridges, tunnels and buildings; underground utility and void sensing" of the COST (European COoperation in Science and Technology) Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar" (www.GPRadar.eu, www.cost.eu). The principal goal of the Action, started in April 2013 and ending in October 2017, is to exchange and increase scientific-technical knowledge and experience of Ground Penetrating Radar (GPR) techniques in civil engineering, whilst promoting throughout Europe the effective use of this safe non-destructive technique. The Action involves more than 300 Members from 28 COST Countries, a Cooperating State, 6 Near Neighbour Countries and 6 International Partner Countries. The most interesting achievements of WG2 include: 1. The state of the art on the use of GPR in civil engineering was composed and open issues were identified. The few existing international/national guidelines/protocols for GPR inspection in civil engineering were reviewed and discussed. Academic end-users, private companies and stakeholders presented their point of view and needs. 2. Guidelines for investigating flexible pavement by using GPR were prepared, with particular regard to layer-thickness assessment, moisture-content sensing, pavement-damage detection and classification, and other main GPR-based investigations in pavement engineering. 3. Guidelines for GPR sensing and mapping of underground utilities and voids were prepared, with a main focus on urban areas. 4. Guidelines for GPR assessment of concrete structures, with particular regard to inspections in bridges and tunnels, were prepared. 5. A report was composed, including a series of practical suggestions and very useful information to guide GPR users during building inspection. 6. WG2 Members carried out a plethora of case studies where GPR was used to survey roads, highways, airport runways, car

  12. Transport processes in partially saturate concrete: Testing and liquid properties

    NASA Astrophysics Data System (ADS)

    Villani, Chiara

    properties and pore structure information as inputs. Concrete exposed to deicing salts resulted to have a reduced gas transport due to the higher degree of saturation (DOS). The higher DOS is believed to contribute to the premature deterioration observed in concrete pavements exposed to deicing salts. Moisture diffusion and moisture profiles in concrete are known to directly relate with the stresses generated during shrinkage and creep mechanisms. The alteration due to the presence of shrinkage reducing admixtures on drying was also investigated in this work. Liquid properties were used to predict the diffusion coefficient in presence of SRA. Moisture profiles obtained using Fick's second law for diffusion were compared to relative humidity profiles measured on concrete slabs. Results confirm that a qualitative prediction of drying in concrete elements is realistic when using this type of approach.

  13. The evaluation of ordinary Portland cement concrete subject to elevated temperatures in conjunction with acoustic emission and splitting tensile test

    NASA Astrophysics Data System (ADS)

    Su, Yu-Min; Hou, Tsung-Chin; Chen, Guan-Ying; Hou, Ping-Ni

    2017-04-01

    The research objective was to evaluate Ordinary Portland Cement concrete subject to various elevated temperatures. Single OPC concrete mixture with water to cementitious (w/c) equal to 0.45 was proportioned. Concrete specimens were cast and placed in the curing tank in which water was saturated with calcium hydroxide. After ninety days of moist-cure, three elevated temperatures, namely 300, 600, and 900-°C, were carried out upon hardened concrete specimens. Furthermore, two post-damaged curing conditions were executed to recover damaged concrete specimens: one was to recure under 23°C with 50% humidity in a controlled environmental chamber and the other was to recure in the same curing tank. Acoustic emission apparatus coupled with the splitting tensile test was utilized and found able to assess damaged concrete. Before concrete subject to elevated temperatures, the development of indirect tensile strength versus displacement diagram fit well with the tendency of AE energy release. It was found there was a large amount of AE energy released when stress and displacement diagram developed about 40-50%. As such could be identified as the onset of first fracture and the plain concrete generally exhibited a quasi-brittle fracture with two major series of AE energy dissipations; however when concrete specimens were subject to elevated temperatures, the damaged concrete specimens displayed neither fracture pattern nor the "double-hump" AE energy dissipation in comparison with those of plain concrete.

  14. Pavement maintenance optimization model using Markov Decision Processes

    NASA Astrophysics Data System (ADS)

    Mandiartha, P.; Duffield, C. F.; Razelan, I. S. b. M.; Ismail, A. b. H.

    2017-09-01

    This paper presents an optimization model for selection of pavement maintenance intervention using a theory of Markov Decision Processes (MDP). There are some particular characteristics of the MDP developed in this paper which distinguish it from other similar studies or optimization models intended for pavement maintenance policy development. These unique characteristics include a direct inclusion of constraints into the formulation of MDP, the use of an average cost method of MDP, and the policy development process based on the dual linear programming solution. The limited information or discussions that are available on these matters in terms of stochastic based optimization model in road network management motivates this study. This paper uses a data set acquired from road authorities of state of Victoria, Australia, to test the model and recommends steps in the computation of MDP based stochastic optimization model, leading to the development of optimum pavement maintenance policy.

  15. Acoustical estimation of parameters of porous road pavement

    NASA Astrophysics Data System (ADS)

    Valyaev, V. Yu.; Shanin, A. V.

    2012-11-01

    In the simplest case, porous road pavement of a known thickness is described by such parameters as porosity, tortuosity, and flow resistance. The problem of estimating these parameters is investigated in this paper. An acoustic signal reflected by the pavement is used for this. It is shown that this problem can be solved by an experiment conducted in the time domain (i.e., the pulse response of the media is recorded). The incident sound wave is thrown at a grazing angle to the surface between the pavement and the air to improve penetration into the porous medium. The procedure of computing of the pulse response using the Morse-Ingard model is described in detail.

  16. Rheo-mechanical model for self-healing asphalt pavement

    NASA Astrophysics Data System (ADS)

    Gömze, A. L.; Gömze, L. N.

    2017-01-01

    Examining the rheological properties of different asphalt mixtures at different temperatures, pressures and deformation conditions on the combined rheo-tribometers the authors have found that the generally used Burgers-model doesn’t explain the deformation properties of asphalt mixtures and pavements under loading forces and loading pressures. To understand better the rheological and deformation properties of such complex materials like asphalt mixtures and pavements the authors used Malvern Mastersizer X laser granulometer, Bruker D8 Advance X-ray diffractometer, Hitachi TM 1000 Scanning Elektronmicroscope, Tristar 3000 specific surface tester and the combined rheo-tribometer developed and patented by the authors. After the complex investigation of different asphalt mixtures the authors have found a new, more complex rheological model for the asphalts including self-healing asphalt pavements.

  17. Airfield Rigid Pavement Structural Design—A Review of Main Aspects and Methods of Analysis

    NASA Astrophysics Data System (ADS)

    Tiago Bonucci, Pereira

    2010-05-01

    Airfield pavements present a number of characteristics that make their design considerably different from that of road pavements. Apart from load magnitude and it's frequency, maintenance issues and pavement strength classification reporting are aspects that must be considered in the design phase. In the present paper, these aspects are analysed in the light of traditional and new methods of airfield pavement analysis. Parametric studies are performed in order to study the effects of different factors, such as pavement structure, layer thickness, material strength, effects of temperature, load transfer across joints and traffic characteristics.

  18. Subsurface defect detection in first layer of pavement structure and reinforced civil engineering structure by FRP bonding using active infrared thermography

    NASA Astrophysics Data System (ADS)

    Dumoulin, Jean; Ibos, Laurent

    2010-05-01

    In many countries road network ages while road traffic and maintenance costs increase. Nowadays, thousand and thousand kilometers of roads are each year submitted to surface distress survey. They generally lean on pavement surface imaging measurement techniques, mainly in the visible spectrum, coupled with visual inspection or image processing detection of emergent distresses. Nevertheless, optimisation of maintenance works and costs requires an early detection of defects within the pavement structure when they still are hidden from surface. Accordingly, alternative measurement techniques for pavement monitoring are currently under investigation (seismic methods, step frequency radar). On the other hand, strengthening or retrofitting of reinforced concrete structures by externally bonded Fiber Reinforced Polymer (FRP) systems is now a commonly accepted and widespread technique. However, the use of bonding techniques always implies following rigorous installing procedures. To ensure the durability and long-term performance of the FRP reinforcements, conformance checking through an in situ auscultation of the bonded FRP systems is then highly suitable. The quality-control program should involve a set of adequate inspections and tests. Visual inspection and acoustic sounding (hammer tap) are commonly used to detect delaminations (disbonds) but are unable to provide sufficient information about the depth (in case of multilayered composite) and width of debonded areas. Consequently, rapid and efficient inspection methods are also required. Among the non destructive methods under study, active infrared thermography was investigated both for pavement and civil engineering structures through experiments in laboratory and numerical simulations, because of its ability to be also used on field. Pulse Thermography (PT), Pulse Phase Thermography (PPT) and Principal Component Thermography (PCT) approaches have been tested onto pavement samples and CFRP bonding on concrete

  19. An algorithm for pavement crack detection based on multiscale space

    NASA Astrophysics Data System (ADS)

    Liu, Xiang-long; Li, Qing-quan

    2006-10-01

    Conventional human-visual and manual field pavement crack detection method and approaches are very costly, time-consuming, dangerous, labor-intensive and subjective. They possess various drawbacks such as having a high degree of variability of the measure results, being unable to provide meaningful quantitative information and almost always leading to inconsistencies in crack details over space and across evaluation, and with long-periodic measurement. With the development of the public transportation and the growth of the Material Flow System, the conventional method can far from meet the demands of it, thereby, the automatic pavement state data gathering and data analyzing system come to the focus of the vocation's attention, and developments in computer technology, digital image acquisition, image processing and multi-sensors technology made the system possible, but the complexity of the image processing always made the data processing and data analyzing come to the bottle-neck of the whole system. According to the above description, a robust and high-efficient parallel pavement crack detection algorithm based on Multi-Scale Space is proposed in this paper. The proposed method is based on the facts that: (1) the crack pixels in pavement images are darker than their surroundings and continuous; (2) the threshold values of gray-level pavement images are strongly related with the mean value and standard deviation of the pixel-grey intensities. The Multi-Scale Space method is used to improve the data processing speed and minimize the effectiveness caused by image noise. Experiment results demonstrate that the advantages are remarkable: (1) it can correctly discover tiny cracks, even from very noise pavement image; (2) the efficiency and accuracy of the proposed algorithm are superior; (3) its application-dependent nature can simplify the design of the entire system.

  20. Pore-structure models of hydraulic conductivity for permeable pavement

    NASA Astrophysics Data System (ADS)

    Kuang, X.; Sansalone, J.; Ying, G.; Ranieri, V.

    2011-03-01

    SummaryPermeable pavement functions as a porous infrastructure interface allowing the infiltration and evaporation of rainfall-runoff while functioning as a relatively smooth load-bearing surface for vehicular transport. Hydraulic conductivity ( k) of permeable pavement is an important hydraulic property and is a function of the pore structure. This study examines k for a cementitious permeable pavement (CPP) through a series of pore-structure models. Measurements utilized include hydraulic head as well as total porosity, ( ϕ t), effective porosity ( ϕ e), tortuosity ( L e/ L) and pore size distribution (PSD) indices generated through X-ray tomography (XRT). XRT results indicate that the permeable pavement pore matrix is hetero-disperse, with high tortuosity and ϕ t ≠ ϕ e. Power law models of k- ϕ t and k- ϕ e relationships are developed for a CPP mix design. Results indicate that the Krüger, Fair-Hatch, Hazen, Slichter, Beyer and Terzaghi models based on simple pore-structure indices do not reproduce measured k values. The conventional Kozeny-Carman model (KCM), a more parameterized pore-structure model, did not reproduce measured k values. This study proposes a modified KCM utilizing ϕ e, specific surface area (SSA) pe and weighted tortuosity ( L e/ L) w. Results demonstrate that such permeable pavement pore-structure parameters with the modified KCM can predict k. The k results are combined with continuous simulation modeling using historical rainfall to provide nomographs examining permeable pavement as a low impact development (LID) infrastructure component.

  1. Reinforced Concrete Modeling

    DTIC Science & Technology

    1982-07-01

    AFWL-TR-82-9 AFWL-TR-82-9 REINFORCED CONCRETE MODELING H. L. Schreyer J. W. Jeter, Jr. New Mexico Engineering Reseprch Institute University of New...Subtitle) S. TYPE OF REPORT & PERIOD COVERED REINFORCED CONCRETE MODELING Final Report 6. PERFORMING OtG. REPORT NUMBER NMERI TA8-9 7. AUTHORg) S...loading were identified and used to evaluate current concrete models . Since the endochronic and viscoplastic models provide satisfactory descriptions

  2. Plains Tectonics on Venus

    NASA Technical Reports Server (NTRS)

    Banerdt, W. B.; McGill, G. E.; Zuber, M. T.

    1996-01-01

    Tectonic deformation in the plains of Venus is pervasive, with virtually every area of the planet showing evidence for faulting or fracturing. This deformation can be classified into three general categories, defined by the intensity and areal extent of the surface deformation: distributed deformation, concentrated deformation, and local fracture patterns.

  3. Mountain-Plains Curriculum.

    ERIC Educational Resources Information Center

    Mountain-Plains Education and Economic Development Program, Inc., Glasgow AFB, MT.

    The document lists the Mountain-Plains curriculum by job title (where applicable), including support courses. The curriculum areas covered are mathematics skills, communication skills, office education, lodging services, food services, marketing and distribution, welding support, automotive, small engines, career guidance, World of Work, health…

  4. Mountain-Plains Curriculum.

    ERIC Educational Resources Information Center

    Mountain-Plains Education and Economic Development Program, Inc., Glasgow AFB, MT.

    The document lists the Mountain-Plains curriculum by job title (where applicable), including support courses. The curriculum areas covered are mathematics skills, communication skills, office education, lodging services, food services, marketing and distribution, welding support, automotive, small engines, career guidance, World of Work, health…

  5. Evaluation of multilayered pavement structures from measurements of surface waves

    USGS Publications Warehouse

    Ryden, N.; Lowe, M.J.S.; Cawley, P.; Park, C.B.

    2006-01-01

    A method is presented for evaluating the thickness and stiffness of multilayered pavement structures from guided waves measured at the surface. Data is collected with a light hammer as the source and an accelerometer as receiver, generating a synthetic receiver array. The top layer properties are evaluated with a Lamb wave analysis. Multiple layers are evaluated by matching a theoretical phase velocity spectrum to the measured spectrum. So far the method has been applied to the testing of pavements, but it may also be applicable in other fields such as ultrasonic testing of coated materials. ?? 2006 American Institute of Physics.

  6. Tactile pavement for guiding walking direction: An assessment of heading direction and gait stability.

    PubMed

    Pluijter, Nanda; de Wit, Lieke P W; Bruijn, Sjoerd M; Plaisier, Myrthe A

    2015-10-01

    For maintaining heading direction while walking we heavily rely on vision. Therefore, walking in the absence of vision or with visual attention directed elsewhere potentially leads to dangerous situations. Here we investigated whether tactile information from the feet can be used as a (partial) substitute for vision in maintaining a stable heading direction. If so, participants should be better able to keep a constant heading direction on tactile pavement that indicates directionality than on regular flat pavement. However, such a pavement may also be destabilizing. Thus we asked participants to walk straight ahead on regular pavement, and on tactile pavement (tiles with ridges along the walking direction) while varying the amount of vision. We assessed the effects of the type of pavement as well as the amount of vision on the variability of the heading direction as well as gait stability. Both of these measures were calculated from accelerations and angular velocities recorded from a smartphone attached to the participants trunk. Results showed that on tactile pavement participants had a less variations in their heading direction than on regular pavement. The drawback, however, was that the tactile pavement used in this study decreased gait stability. In sum, tactile pavement can be used as a partial substitute for vision in maintaining heading direction, but it can also decrease gait stability. Future work should focus on designing tactile pavement that does provided directional clues, but is less destabilizing.

  7. Vibration of vehicle-pavement coupled system based on a Timoshenko beam on a nonlinear foundation

    NASA Astrophysics Data System (ADS)

    Ding, Hu; Yang, Yan; Chen, Li-Qun; Yang, Shao-Pu

    2014-12-01

    This paper focuses on the coupled nonlinear vibration of vehicle-pavement system. The pavement is modeled as a Timoshenko beam resting on a six-parameter foundation. The vehicle is simplified as a spring-mass-damper oscillator. For the first time, the dynamic response of vehicle-pavement coupled system is studied by modeling the pavement as a Timoshenko beam resting on a nonlinear foundation. Consequently, the shear effects and the rotational inertia of the pavement are included in the modeling process. The pavement model is assumed to be a linear-plus-cubic Pasternak-type foundation. Furthermore, the convergent Galerkin truncation is used to obtain approximate solutions to the coupled vibratory response of the vehicle-pavement coupled system. The dynamic responses of the vehicle-pavement system with the asphalt pavement on soft soil foundation are investigated via the numerical examples. The numerical results show that the calculation for the coupled vibratory response needs high-order modes. Moreover, the coupling effects between the pavement and the vehicle are numerically examined by using the convergent modal truncation. The physical parameters of the vehicle-pavement system such as the shear modulus are compared for determining their influences on the coupled vibratory response.

  8. Deterioration modeling for condition assessment of flexible pavements considering extreme weather events

    NASA Astrophysics Data System (ADS)

    Hashemi Tari, Yasamin; Shahini Shamsabadi, Salar; Birken, Ralf; Wang, Ming

    2015-04-01

    Accurate pavement management systems are essential for states' Department Of Transportation and roadway agencies to plan for cost-effective maintenance and repair (M and R) strategies. Pavement deterioration model is an imperative component of any pavement management system since the future budget and M and R plans would be developed based on the predicted pavement performance measures. It is crucial for the pavement deterioration models to consider the factors that significantly aggravate the pavement condition. While many studies have highlighted the impact of different environmental, load, and pavement's structure on the life cycle of the pavement, effect of extreme weather events such as Floods and Snow Storms have often been overlooked. In this study, a pavement deterioration model is proposed which would consider the effect of traffic loads, climate conditions, and extreme weather events. Climate, load and performance data has been compiled for over twenty years and for eight states using the Long Term Pavement Performance (LTPP) and National Oceanic and Atmospheric Administration (NOAA) databases. A stepwise regression approach is undertaken to quantify the effect of the extreme weather events, along with other influential factors on pavement performance in terms of International Roughness Index (IRI). Final results rendered more than 90% correlation with the quantified impact values of extreme weather events.

  9. Strain rate effects for concrete and fiber-reinforced concrete subjected to impact loading. Final report, September 1982-August 1987

    SciTech Connect

    Shah, S.P.

    1987-10-01

    Despite it's extensive use, low tensile strength has been recognized as one of the major drawbacks of concrete. Although one has learned to avoid exposing concrete structures to adverse static tensile loads, these structures cannot be shielded from short duration dynamic tensile loads. Such loads originate from sources such as impact from missiles and projectiles, wind gusts, earthquakes and machine vibrations. In addition, modern computer-aided analysis and use of concrete for special structures such as reactor containment vessels, missile storage silos and fall-out shelters, has led to a growing interest in the cracking behavior of concrete. Experimental results indicate that the fracture strength and cracking behavior of concrete are affected by the rate of loading. To accurately predict the structural response under impact conditions, the knowledge of behavior of concrete at high rates of loading is essential. Using a two degree of freedom model guidelines were developed for designing an impact test setup, thus enabling one to conduct impact tests free of adverse inertial effects. Based on these guidelines, the author has developed an instrumented modified Charpy impact testing system. This experimental test setup was used to obtain basic information such as load-deflection relationship, fracture toughness, crack velocity (measured using Krak Gages), and load-strain history during an impact fracture event of plain concrete and SFRC.

  10. The Productivity of Plain English.

    ERIC Educational Resources Information Center

    Department of Commerce, Washington, DC.

    Focusing on a meeting held in January 1983, this pamphlet describes the Forum on the Productivity of Plain English, from which grew the permanent Plain English Forum, which is committed to spreading the message that plain English is good business. The pamphlet includes quotations from leaders in business and industry explaining why they feel that…

  11. Functionality Enhancement of Industrialized Optical Fiber Sensors and System Developed for Full-Scale Pavement Monitoring

    PubMed Central

    Wang, Huaping; Liu, Wanqiu; He, Jianping; Xing, Xiaoying; Cao, Dandan; Gao, Xipeng; Hao, Xiaowei; Cheng, Hongwei; Zhou, Zhi

    2014-01-01

    Pavements always play a predominant role in transportation. Health monitoring of pavements is becoming more and more significant, as frequently suffering from cracks, rutting, and slippage renders them prematurely out of service. Effective and reliable sensing elements are thus in high demand to make prognosis on the mechanical properties and occurrence of damage to pavements. Therefore, in this paper, various types of functionality enhancement of industrialized optical fiber sensors for pavement monitoring are developed, with the corresponding operational principles clarified in theory and the performance double checked by basic experiments. Furthermore, a self-healing optical fiber sensing network system is adopted to accomplish full-scale monitoring of pavements. The application of optical fiber sensors assembly and self-healing network system in pavement has been carried out to validate the feasibility. It has been proved that the research in this article provides a valuable method and meaningful guidance for the integrity monitoring of civil structures, especially pavements. PMID:24854060

  12. Durability assessments of concrete using electrical properties and acoustic emission testing

    NASA Astrophysics Data System (ADS)

    Todak, Heather N.

    Premature damage deterioration has been observed in pavement joints throughout the Midwestern region of the United States. Over time, severe joint damage creates a transportation safety concern and the necessary repairs can be an extreme economic burden. The deterioration is due in part to freeze-thaw damage associated with fluid accumulation at the pavement joints. This very preventable problem is an indication that current specifications and construction practices for freeze-thaw durability of concrete are inadequate. This thesis serves to create a better understanding of moisture ingress, freeze-thaw damage mechanisms, and the effect of variations in mixture properties on freeze-thaw behavior of concrete. The concepts of the nick point degree of saturation, sorptivity rates, and critical degree of saturation are discussed. These factors contribute to service life, defined in this study as the duration of time a concrete element remains below levels of critical saturation which are required for damage development to initiate. A theoretical model and a simple experimental procedure are introduced which help determine the nick point for a series of 32 concrete mixtures with unique mixture proportions and air entrainment properties. This simple experimental procedure is also presented as a method to measure important electrical properties in order to establish the formation factor, a valuable measure of concrete transport properties. The results of freeze-thaw testing with acoustic emission monitoring are presented to help understand and quantify damage development in concrete specimens when conditioned to various degrees of saturation. This procedure was used to study the relationship between air entrainment properties and the critical degree of saturation. Applying the concepts of degree of saturation and sorptivity, a performance-based model is proposed as a new approach to specifications for freeze-thaw durability. Finally, a conceptual model is presented to

  13. Research on deformation characteristics and design method of concrete beams reinforced with GFRP bars

    NASA Astrophysics Data System (ADS)

    Pan, M. X.; Xu, X. S.

    2017-04-01

    Two different glass fiber reinforced polymer (GFRP) bars were produced to reinforce concrete beams, including plain GFRP bars and ribbed surface GFRP bars. The flexural property of GFRP reinforced concrete beams was studied by testing four specimen beams under two point vertical loads. The crack development and stain distribution of beam cross section during loading were recorded, and the deformation characteristics and failure mode were also analyzed in this experiment. According to the test results, the bond property of plain GFRP bars was too poor to serve as reinforcement bars, while the ribbed surface GFRP bars showed good bond performance and worked well with concrete before final failure. The test beam reinforced with ribbed surface GFRP bars exhibited a uniform crack distribution, and the strain agreed with the assumption of plane cross section. Moreover, calculation method for bending capacity of concrete beam strengthened with GFRP bars was deducted based on this experiment.

  14. 51. DETAIL VIEW OF VIVIANNA ERA CONCRETE HOUSE WITH CONCRETE ...

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

    51. DETAIL VIEW OF VIVIANNA ERA CONCRETE HOUSE WITH CONCRETE PATIO SLAB LOOKING SOUTHWEST. NOTICE MINE WORKINGS BACKGROUND LEFT. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  15. Performance and Characterization of Geopolymer Concrete Reinforced with Short Steel Fiber

    NASA Astrophysics Data System (ADS)

    Abdullah, M. M. A. B.; Faris, M. A.; Tahir, M. F. M.; Kadir, A. A.; Sandu, A. V.; Mat Isa, N. A. A.; Corbu, O.

    2017-06-01

    In the recent years, geopolymer concrete are reporting as the greener construction technology compared to conventional concrete that made up of ordinary Portland cement. Geopolymer concrete is an innovative construction material that utilized fly ash as one of waste material in coal combustion industry as a replacement for ordinary Portland cement in concrete. The uses of fly ash could reduce the carbon dioxide emission to the atmosphere, redundant of fly ash waste and costs compared to ordinary Portland cement concrete. However, the plain geopolymer concrete suffers from numerous drawbacks such as brittleness and low durability. Thus, in this study the addition of steel fiber is introduced in plain geopolymer concrete to improve its mechanical properties especially in compressive and flexural strength. Characterization of raw materials also determined by using chemical composition analysis. Short type of steel fiber is added to the mix in weight percent of 1 wt%, 3 wt%, 5 wt% and 7 wt% with fixed molarity of sodium hydroxide of 12M and solid to liquid ratio as 2.0. The addition of steel fiber showed the excellent improvement in the mechanical properties of geopolymer concrete that are determined by various methods available in the literature and compared with each other.

  16. Evaluation of Precast Portland Cement Concrete Panels for Airfield Pavement Repairs

    DTIC Science & Technology

    2015-05-01

    88 5.6 FEM results...89 Figure 5.4. Example of FEM -predicted and calculated (theory) shear forces...B.6. Securing formwork to solid surface: (a) drilling anchor hole, (b-d) installing and activating the anchor

  17. Evaluation of maintenance/rehabilitation alternatives for continuously reinforced concrete pavement

    NASA Astrophysics Data System (ADS)

    Barnett, T. L.; Darter, M. I.; Laybourne, N. R.

    1981-05-01

    The design, construction, performance, and costs of several maintenance and rehabilitation methods were evaluated. Patching, cement grout and asphalt undersealing, epoxying of cracks, and an asphalt overlay were considered. Nondestructive testing, deflections, reflection cracking, cost, and statistical analyses were used to evaluate the methods.

  18. Criteria for Asphalt-Rubber Concrete in Civil Airport Pavements: Mixture Design.

    DTIC Science & Technology

    1986-07-01

    8217s. These early experiments included the introduction of various forms of rubber (including latex, devulcanized or reclaimed rubber, raw and ground...addition to rubber morphology, the size of the rubber particles and whether the rubber has been processed after grinding, i.e., devulcanized , both...Method B. Method A uses ground reclaimed " devulcanized " rubber and an extender oil whereas Method B uses ground reclaimed vulcanized rubber and a kerosene

  19. Thermochemical Concrete Pavement Scaling Mechanism: Navy F/A-18 Jet Aircraft Parking Apron Problem

    DTIC Science & Technology

    1998-06-01

    Ca3 (P04)2 phosphoric acid calcium carbonate (b) CaSi03 + calcium silicate (c)CaAl204 + calcium aluminate (top carbonated crust... calcium phosphate H3P04 -» Ca3 (P04)2 (cement paste) phosphoric acid calcium phosphate H3P04 -> Ca3 (P04)2 (cement paste) phosphoric acid...carbonate (H) water 2. The parallel between calcium hydroxide and potassium hydroxide is not very accurate. Potassium hydroxide is a much stronger alkali

  20. HIGH-COMPRESSIVE-STRENGTH CONCRETE.

    DTIC Science & Technology

    CONCRETE , COMPRESSIVE PROPERTIES), PERFORMANCE(ENGINEERING), AGING(MATERIALS), MANUFACTURING, STRUCTURES, THERMAL PROPERTIES, CREEP, DEFORMATION, REINFORCED CONCRETE , MATHEMATICAL ANALYSIS, STRESSES, MIXTURES, TENSILE PROPERTIES

  1. Monitoring Strategies in Permeable Pavement Systems to Optimize Maintenance Scheduling

    EPA Science Inventory

    As the surface in a permeable pavement system clogs and performance decreases, maintenance is required to preserve the design function. Currently, guidance is limited for scheduling maintenance on an as needed basis. Previous research has shown that surface clogging in a permea...

  2. Evaluation of Nontraditional Airfield Pavement Surfaces for Contingency Operations

    DTIC Science & Technology

    2014-01-01

    ER D C/ G SL T R -1 4 -2 Evaluation of Nontraditional Airfield Pavement Surfaces for Contingency Operations G eo te ch n ic al a n d...Performance of geogrid stabilized gravel flexible base with bituminous surface treatment. ERDC/GSL TR (in preparation). Vicks- burg , MS: US Army Engineer

  3. Use of noncontact sensors for paving operations on airport pavements

    NASA Astrophysics Data System (ADS)

    Lenngren, Carl A.

    1999-01-01

    The Swedish National Road Administration has been using a laser range finder system for assessing longitudinal and transversa profiles of pavements for a number of years. The Civil Administration has expressed interest in trying automated methods for surveying airfield runways. Regardless of sampling method, the data re used as input for computer aided design of new pavement surfaces. Typically, the output will consist of tables and maps of where to pave and mill the old pavement surface. Adjusting an old surface to perfectly smooth standards may require continuously changing the new pavement layer thickness. Traditionally, this was often carried out with mechanical devices, usually in direct touch with a wire. Some manufacturers now offer non-contact devices for pavers such as ultra sound sensors as an alternative to the mechanical sensors thus eliminating the need for setting up sires. The method was tested in late 1997 after the output data were converted for a design to be read directly by a paver control unit. A larger test was done in the summer of 1998. The results were promising and the Royal Swedish Fortifications Administration decided to try the method on a taxiway in 1999. The present paper describes some of the experiences obtained with this method and computer controlled equipment in general.

  4. Some experience using noncontact sensors on airport pavements

    NASA Astrophysics Data System (ADS)

    Lenngren, Carl A.

    1996-11-01

    The Swedish National Road Administration has been using a laser based system for assessing pavement surface characteristics for over a decade. Typically, important distress data like roughness and rutting are being sampled at speeds up to 25 meters per second. Other parameters include textures and geometric data, such as cross slope and curvature. The Royal Swedish Fortifications Administration has just recently looked into these techniques for airfield pavements. The objectives are similar but not exactly the same as for highway pavements. A promising aspect is using data for building terrain models of the surface so that overlay design procedures can take place in a computerized environment. The objectives are similar but not exactly the same as for highway pavements. A promising aspect is using data for building terrain models of the surface so that overlay design procedures can take place in a computerized environment. Two different ways of treating the data for this purpose was tried. One model uses several parallel continuous longitudinal profiles. The other consists of snap-shot transverse profiles at five meter intervals. The former model yields good assessment of the volumetric needs of either filling or milling operations. The latter is better for identifying features on the surface. The present paper describes some of experiences obtained with the two methods. However, in both cases the most advantageous aspect of using the non-contact devices is the short time needed for collecting the data.

  5. Monitoring Strategies in Permeable Pavement Systems to Optimize Maintenance Scheduling

    EPA Science Inventory

    As the surface in a permeable pavement system clogs and performance decreases, maintenance is required to preserve the design function. Currently, guidance is limited for scheduling maintenance on an as needed basis. Previous research has shown that surface clogging in a permea...

  6. Time series trends of the safety effects of pavement resurfacing.

    PubMed

    Park, Juneyoung; Abdel-Aty, Mohamed; Wang, Jung-Han

    2017-04-01

    This study evaluated the safety performance of pavement resurfacing projects on urban arterials in Florida using the observational before and after approaches. The safety effects of pavement resurfacing were quantified in the crash modification factors (CMFs) and estimated based on different ranges of heavy vehicle traffic volume and time changes for different severity levels. In order to evaluate the variation of CMFs over time, crash modification functions (CMFunctions) were developed using nonlinear regression and time series models. The results showed that pavement resurfacing projects decrease crash frequency and are found to be more safety effective to reduce severe crashes in general. Moreover, the results of the general relationship between the safety effects and time changes indicated that the CMFs increase over time after the resurfacing treatment. It was also found that pavement resurfacing projects for the urban roadways with higher heavy vehicle volume rate are more safety effective than the roadways with lower heavy vehicle volume rate. Based on the exploration and comparison of the developed CMFucntions, the seasonal autoregressive integrated moving average (SARIMA) and exponential functional form of the nonlinear regression models can be utilized to identify the trend of CMFs over time. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Impact of Snow Removal Operations on Thermoplastic Pavement Markings

    DTIC Science & Technology

    2011-03-01

    18 2.3.6 TRB Synthesis (Migletz & Graham, 2001) ..................................................... 20 2.3.7 Michigan 1999...operations do  Linear regression used 1999 Michigan Lee, Maleck, Taylor Pavement Marking Material Evaluation Study in Michigan ...retroreflectometers manufactured by Flint Trading; the LTL-2000 is a predecessor of the LTL-X model. Handheld retroreflectometers must meet three

  8. Modeling the Hydrologic Processes of a Permeable Pavement ...

    EPA Pesticide Factsheets

    A permeable pavement system can capture stormwater to reduce runoff volume and flow rate, improve onsite groundwater recharge, and enhance pollutant controls within the site. A new unit process model for evaluating the hydrologic performance of a permeable pavement system has been developed in this study. The developed model can continuously simulate infiltration through the permeable pavement surface, exfiltration from the storage to the surrounding in situ soils, and clogging impacts on infiltration/exfiltration capacity at the pavement surface and the bottom of the subsurface storage unit. The exfiltration modeling component simulates vertical and horizontal exfiltration independently based on Darcy’s formula with the Green-Ampt approximation. The developed model can be arranged with physically-based modeling parameters, such as hydraulic conductivity, Manning’s friction flow parameters, saturated and field capacity volumetric water contents, porosity, density, etc. The developed model was calibrated using high-frequency observed data. The modeled water depths are well matched with the observed values (R2 = 0.90). The modeling results show that horizontal exfiltration through the side walls of the subsurface storage unit is a prevailing factor in determining the hydrologic performance of the system, especially where the storage unit is developed in a long, narrow shape; or with a high risk of bottom compaction and clogging. This paper presents unit

  9. The Edison Environmental Center Permeable Pavement Site - slides

    EPA Science Inventory

    This is a presentation for a second Community Outreach Event called "Chemistry Works!" at West Windsor Public Library on Saturday, November 5th. It will review the permeable pavement research project at the Edison Environmental center. Besides slide persentation, two demo units w...

  10. Measuring Clogging with Pressure Transducers in Permeable Pavement Strips

    EPA Science Inventory

    Two issues that have a negative affect on the long term hydrologic performance of permeable pavement systems are surface clogging and clogging at the interface with the underlying soil. Surface clogging limits infiltration capacity and results in bypass if runoff rate exceeds in...

  11. Monitoring pavement response and performance using in-situ instrumentation

    SciTech Connect

    Chen, D.H.; Bilyeu, J.; Hugo, F.

    1999-07-01

    The purpose of this paper is to present the effectiveness of in-situ instrumentation on diagnosing the pavement layer conditions under full-scale accelerated traffic loading. The test section is an in-service pavement (US281) in Jacksboro, Texas. Multi-Depth Deflectometers (MDDs) are used to measure both permanent deformations and transient deflections, caused by accelerated traffic loading and Falling Weight Deflectometers (MDDs) are used to measure both permanent deformations and transient deflections, caused by accelerated traffic loading and Falling Weight Deflectometer (FWD) tests. Four different FWD loads of 25, 40, 52, and 67 kN were applied in close proximity to the MDDs at various traffic loading intervals to determine pavement conditions. It was found that the majority of rutting occurred in the newly recycled asphalt mix. The aged ({gt}40 years) underlying base and subgrade layers contributed less than 30% to overall rutting. Only the top recycled Asphalt layer underwent notable deterioration due to traffic loading. Up to 1.5 million axle repetitions, the test pad responded to FWD load almost linearly, not only over the whole pavement system but also within individual layers. However, under higher FWD loads, the percentage of total deflection contributed by the subgrade increased.

  12. Measuring Clogging with Pressure Transducers in Permeable Pavement Strips

    EPA Science Inventory

    Two issues that have a negative affect on the long term hydrologic performance of permeable pavement systems are surface clogging and clogging at the interface with the underlying soil. Surface clogging limits infiltration capacity and results in bypass if runoff rate exceeds in...

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

    NASA Astrophysics Data System (ADS)

    Rajbongshi, Pabitra; Thongram, Sonika

    2016-09-01

    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.

  14. Evaluating Pavement Cracks with Bidimensional Empirical Mode Decomposition

    NASA Astrophysics Data System (ADS)

    Ayenu-Prah, Albert; Attoh-Okine, Nii

    2008-12-01

    Crack evaluation is essential for effective classification of pavement cracks. Digital images of pavement cracks have been analyzed using techniques such as fuzzy set theory and neural networks. Bidimensional empirical mode decomposition (BEMD), a new image analysis method recently developed, can potentially be used for pavement crack evaluation. BEMD is an extension of the empirical mode decomposition (EMD), which can decompose nonlinear and nonstationary signals into basis functions called intrinsic mode functions (IMFs). IMFs are monocomponent functions that have well-defined instantaneous frequencies. EMD is a sifting process that is nonparametric and data driven; it does not depend on an a priori basis set. It is able to remove noise from signals without complicated convolution processes. BEMD decomposes an image into two-dimensional IMFs. The present paper explores pavement crack detection using BEMD together with the Sobel edge detector. A number of images are filtered with BEMD to remove noise, and the residual image analyzed with the Sobel edge detector for crack detection. The results are compared with results from the Canny edge detector, which uses a Gaussian filter for image smoothing before performing edge detection. The objective is to qualitatively explore how well BEMD is able to smooth an image for more effective edge detection with the Sobel method.

  15. The Edison Environmental Center Permeable Pavement Site - slides

    EPA Science Inventory

    This is a presentation for a second Community Outreach Event called "Chemistry Works!" at West Windsor Public Library on Saturday, November 5th. It will review the permeable pavement research project at the Edison Environmental center. Besides slide persentation, two demo units w...

  16. Northern Plains of Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    22 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a typical view of the martian northern plains. Thousands of square kilometers of the northern middle and polar latitudes of Mars look similar to the scene in this image. In late spring and in summer, dust devils crisscross the northern plains, leaving a variety of dark streaks. The streaks do not survive from year to year, indicating their ephemeral nature. The circular features in this image, including the prominent bright circular feature near the bottom, are the locations of buried meteor impact craters. This image is located near 58.1oN, 207.6oW, and covers an area approximately 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  17. Empirical prediction of mechanical properties of flexible pavement through GPR

    NASA Astrophysics Data System (ADS)

    Bianchini Ciampoli, Luca; Benedetto, Andrea

    2017-04-01

    To date, it is well known that the frequency of accidental events recorded on a road, is related to the deterioration rate of its pavement. In this sense, the monitoring of the pavement health over a road network is a crucial task for the administrations, to define a priority scale for maintenance works, and accordingly to lower the risk of accidents. Several studies suggest the possibility to employ Ground-penetrating Radar (GPR) to overcome the limits of traditional bearing tests, which due to their low productivity and high costs, can only give a discrete knowledge about the strength of the pavement. This work presents a GPR-based empirical model for the prediction of the bearing capacity of a road pavement, expressed as Young's Modulus. The model exploits the GPR to extract information on the thickness of the base course and the clay content, by referring to the signal velocity and attenuation, respectively. To test the effectiveness of the model, experimental activities have been accounted for. In particular, multi-frequency GPR tests have been performed along road sections of rural roads, composed of a flexible pavement, for a total of 45 Km. As ground-truth, light falling weight deflectometer (LFWD) and Curviameter have been employed. Both the electromagnetic and the mechanical datasets have been properly processed, in order to reduce misinterpretations and to raise the statistical significance of the procedure. Hence, the calibration of the parameters composing the model was run in a subsection, equal to 8% of the total length, randomly selected within the surveyed track. Finally, as validation, the model has been applied to the whole analysed dataset. As a result, the empirical model showed a good effectiveness in predicting the mechanical response of the pavement, with a normalised root mean squared deviation equal to 0.27. Finally, by averaging the measured and predicted mechanical data every 50 m and sorting the results into strength classes, a

  18. Cracked Plain, Buried Craters

    NASA Technical Reports Server (NTRS)

    2004-01-01

    4 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a cracked plain in western Utopia Planitia. The three circular crack patterns indicate the location of three buried meteor impact craters. These landforms are located near 41.9oN, 275.9oW. The image covers an area approximately 3 km (1.9 mi) across. Sunlight illuminates this scene from the lower left.

  19. Ice Mountains and Plains

    NASA Image and Video Library

    2015-09-24

    High-resolution images of Pluto taken by NASA's New Horizons spacecraft just before closest approach on July 14, 2015, are the sharpest images to date of Pluto's varied terrain-revealing details down to scales of 270 meters. In this 75-mile (120-kilometer) section taken from the larger, high-resolution mosaic, the textured surface of the plain surrounds two isolated ice mountains. http://photojournal.jpl.nasa.gov/catalog/PIA19954

  20. Accuracy analysis of point cloud modeling for evaluating concrete specimens

    NASA Astrophysics Data System (ADS)

    D'Amico, Nicolas; Yu, Tzuyang

    2017-04-01

    Photogrammetric methods such as structure from motion (SFM) have the capability to acquire accurate information about geometric features, surface cracks, and mechanical properties of specimens and structures in civil engineering. Conventional approaches to verify the accuracy in photogrammetric models usually require the use of other optical techniques such as LiDAR. In this paper, geometric accuracy of photogrammetric modeling is investigated by studying the effects of number of photos, radius of curvature, and point cloud density (PCD) on estimated lengths, areas, volumes, and different stress states of concrete cylinders and panels. Four plain concrete cylinders and two plain mortar panels were used for the study. A commercially available mobile phone camera was used in collecting all photographs. Agisoft PhotoScan software was applied in photogrammetric modeling of all concrete specimens. From our results, it was found that the increase of number of photos does not necessarily improve the geometric accuracy of point cloud models (PCM). It was also found that the effect of radius of curvature is not significant when compared with the ones of number of photos and PCD. A PCD threshold of 15.7194 pts/cm3 is proposed to construct reliable and accurate PCM for condition assessment. At this PCD threshold, all errors for estimating lengths, areas, and volumes were less than 5%. Finally, from the study of mechanical property of a plain concrete cylinder, we have found that the increase of stress level inside the concrete cylinder can be captured by the increase of radial strain in its PCM.