Science.gov

Sample records for aboveground roofed design

  1. Aboveground roofed design for the disposal of low-level radioactive waste in Maine

    SciTech Connect

    Alexander, J.A.

    1993-03-01

    The conceptual designs proposed in this report resulted from a study for the Maine Low-level Radioactive Waste Authority to develop conceptual designs for a safe and reliable disposal facility for Maine`s low-level radioactive waste (LLW). Freezing temperatures, heavy rainfall, high groundwater tables, and very complex and shallow glaciated soils found in Maine place severe constraints on the design. The fundamental idea behind the study was to consider Maine`s climatic and geological conditions at the beginning of conceptual design rather than starting with a design for another location and adapting it for Maine`s conditions. The conceptual designs recommended are entirely above ground and consist of an inner vault designed to provide shielding and protection against inadvertent intrusion and an outer building to protect the inner vault from water. The air dry conditions within the outer building should lead to almost indefinite service life for the concrete inner vault and the waste containers. This concept differs sharply from the usual aboveground vault in its reliance on at least two independent, but more or less conventional, roofing systems for primary and secondary protection against leakage of radioisotopes from the facility. Features include disposal of waste in air dry environment, waste loading and visual inspection by remote-controlled overhead cranes, and reliance on engineered soils for tertiary protection against release of radioactive materials.

  2. Roof structural system, similar in design to peaked roofs of ...

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

    Roof structural system, similar in design to peaked roofs of rolling mill, yet note abandonment of phoenix columns for compression members. - Phoenix Iron Company, Girder Shop No. 6, North of French Creek, west of Gay Street, Phoenixville, Chester County, PA

  3. Cathodic protection design for aboveground storage tanks

    SciTech Connect

    Koszewski, L.; Quincy, G.L.

    1995-12-31

    The application of cathodic protection for aboveground storage tank (AST) bottoms has been accomplished in a variety of approaches, with varying degrees of success. Recent State regulations, requiring corrosion protection for new tanks and secondary containment for double bottom tanks, have prompted new application techniques to be developed for AST cathodic protection. Improved design applications are now available to todays` tank owners and operators to provide effective long term cathodic protection.

  4. Development of design guidelines and roof-control standards for coal-mine roofs

    SciTech Connect

    Unal, E.

    1983-01-01

    Three of the most crucial problems still facing the mining-engineering profession today are that of finding better anchorage testing procedures, effective roof-stability monitoring systems and rationally based design guidelines. First the feasibility of new anchorage-testing procedures and roof-stability monitoring techniques has been investigated through a series of laboratory experiments, utilizing a special instrumented facility and an acoustic emission (AE) monitoring system. Furthermore, two engineering approaches have been used in analyzing the time-dependent behavior of coal-mine roofs and in developing the design guidelines for support selection. The anchorage-testing results provide information on the behavior of the bolt shell and the bolt rod. The bolt capacity is determined from the resulting support characteristic curves which appear to represent a more realistic picture of the behavior of the rock-bolt unit than data presently available from typical field pull-tests. The stability monitoring results indicate a significant correlation between the applied torque, shell movement, bolt-tension and AE. The Integrated Approach is found useful in analyzing the time-dependent behavior of the unsupported and supported roofs, conceptually. The design procedures presented in the Empirical Approach are intended as a guide for selecting rock-bolt types, rock-bolt specifications, bolting patterns, and supplementary support needs for coal-mine roadways as well as for four-way intersections. Furthermore, for a quick reference, in selecting the roof-support options, a series of support charts is presented. Finally, for the step-by-step illustration of the design procedures, a practical example is included.

  5. Field Evaluation of Four Novel Roof Designs for Energy-Efficient Manufactured Homes

    SciTech Connect

    Levy, E.; Dentz, J.; Ansanelli, E.; Barker, G.; Rath, P.; Dadia, D.

    2015-12-01

    A five-bay roof test structure was built, instrumented and monitored in an effort to determine through field testing and analysis the relative contributions of select technologies toward reducing energy use in new manufactured homes. The roof structure in Jamestown, California was designed to examine how differences in roof construction impact space conditioning loads, wood moisture content and attic humidity levels. Conclusions are drawn from the data on the relative energy and moisture performance of various configurations of vented and sealed attics.

  6. View of McKenzieRichey barn showing shed design, rolled roofing and ...

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

    View of McKenzie-Richey barn showing shed design, rolled roofing and wood shed roof, facing southwest - McKenzie Property, Barn, North Bank of Sailor Gulch, 750 feet northwest of intersection of U.S.F.S. Roads 651 & 349, Placerville, Boise County, ID

  7. Field Evaluation of Four Novel Roof Designs for Energy-Efficient Manufactured Homes

    SciTech Connect

    Levy, E.; Dentz, J.; Ansanelli, E.; Barker, G.; Rath, P.; Dadia, D.

    2015-12-03

    "9A five-bay roof test structure was built, instrumented and monitored in an effort to determine through field testing and analysis the relative contributions of select technologies toward reducing energy use in new manufactured homes. The roof structure in Jamestown, California was designed to examine how differences in roof construction impact space conditioning loads, wood moisture content and attic humidity levels. Conclusions are drawn from the data on the relative energy and moisture performance of various configurations of vented and sealed attics.

  8. Design of evaporative-cooling roof for decreasing air temperatures in buildings in the humid tropics

    NASA Astrophysics Data System (ADS)

    Kindangen, Jefrey I.; Umboh, Markus K.

    2017-03-01

    This subject points to assess the benefits of the evaporative-cooling roof, particularly for buildings with corrugated zinc roofs. In Manado, many buildings have roofed with corrugated zinc sheets; because this material is truly practical, easy and economical application. In general, to achieve thermal comfort in buildings in a humid tropical climate, people applying cross ventilation to cool the air in the room and avoid overheating. Cross ventilation is a very popular path to achieve thermal comfort; yet, at that place are other techniques that allow reducing the problem of excessive high temperature in the room in the constructions. This study emphasizes applications of the evaporative-cooling roof. Spraying water on the surface of the ceiling has been executed on the test cell and the reuse of water after being sprayed and cooled once more by applying a heat exchanger. Initial results indicate a reliable design and successfully meet the target as an effective evaporative-cooling roof technique. Application of water spraying automatic and cooling water installations can work optimally and can be an optimal model for the cooling roof as one of the green technologies. The role of heat exchangers can lower the temperature of the water from spraying the surface of the ceiling, which has become a hot, down an average of 0.77° C. The mass flow rate of the cooling water is approximately 1.106 kg/h and the rate of heat flow is around 515 Watt, depend on the site.

  9. A Prototype Roof Deck Designed to Self-Regulate Deck Temperature and Reduce Heat Transfer

    SciTech Connect

    Miller, William A

    2011-01-01

    A prototype roof and attic assembly exploits the use of radiation, convection and insulation controls to reduce the heat transfer penetrating its roof deck by almost 85% of the heat transfer crossing a conventional roof and attic assembly. The assembly exhibited attic air temperatures that did not exceed the peak day outdoor ambient temperature. The design includes a passive ventilation scheme that pulls air from the soffit and attic into an inclined air space above the deck. The design complies with fire protection codes because the air intake is internal and closed to the elements. Field data were benchmarked against an attic computer tool and simulations made for new and retrofit home constructions in hot, moderate and cold climates to access economics for the assembly.

  10. A Prototype Roof Deck Designed to Self-Regulate Deck Temperature and Reduce Heat Transfer

    SciTech Connect

    Miller, William A

    2011-01-01

    A prototype roof and attic assembly exploits the use of radiation, convection and insulation controls to reduce its peak day heat transfer by almost 85 percent of the heat transfer crossing a conventional roof and attic assembly. The assembly exhibits attic air temperatures that do not exceed the maximum daily outdoor ambient temperature. The design includes a passive ventilation scheme that pulls air from the soffit and attic into an inclined air space above the roof deck. The design complies with fire protection codes because the air intake is internal and closed to the elements. Field data were benchmarked against an attic computer tool and simulations made for new and retrofit constructions in hot, moderate and cold climates to gauge the cost of energy savings and potential payback.

  11. Evaluation of a "walk-through" ladder top design during ladder-roof transitioning tasks.

    PubMed

    Simeonov, P; Hsiao, H; Powers, J; Ammons, D; Kau, T; Cantis, D; Zwiener, J; Weaver, D

    2017-03-01

    This study evaluated the effect of an extension ladder "walk-through" top design on kinetic and kinematic behaviors and the outward destabilizing forces induced on the ladder during transitioning at elevation. Thirty-two male participants performed stepping tasks between a ladder top and a roof at simulated elevation in a surround-screen virtual-reality system. The experimental conditions included a "walk-through" and a standard ladder top section supported on flat and sloped roof surfaces. Three force platforms were placed under the ladder section and in the roof to measure propulsion forces during transitions. A motion measurement system was used to record trunk kinematics. The frictional demand at the virtual ladder base was also calculated. The results indicate that under optimal ladder setup (angle 75.5 °), the frictional demand at the ladder base remains relatively small for all experimental conditions. Also, the "walk through" ladder top eased the ladder-to-roof transitions but not the roof-to-ladder transitions.

  12. What's Up with Your Roof?

    ERIC Educational Resources Information Center

    Kalinger, Peter

    1998-01-01

    Explains the importance of knowing what condition the school's roof(s) is in and how to design a preventive maintenance program that is cost effective and will help extend the roof's lifecycle. Cost calculation techniques to value a roof maintenance program, maintenance documentation requirements, and roof surveying are discussed. (GR)

  13. Good Roof Construction Makes Sense.

    ERIC Educational Resources Information Center

    Hubert, Edward F.

    1987-01-01

    A roofing project of any substantial size should involve an architect, an engineer, or a roof consultant. Careful planning and design, diligent construction, and quality inspection, offer owners a quality roof job. (MLF)

  14. Characterization and design of tuned liquid dampers with floating roof considering arbitrary tank cross-sections

    NASA Astrophysics Data System (ADS)

    Ruiz, R. O.; Taflanidis, A. A.; Lopez-Garcia, D.

    2016-04-01

    A recently proposed new type of liquid mass damper, called Tuned Liquid Damper with Floating Roof (TLD-FR), is the focus of this paper. The TLD-FR consists of a traditional TLD (tank filled with liquid) with the addition of a floating roof. The sloshing of the liquid within the tank counteracts the motion of the primary structure it is placed on, offering the desired energy dissipation in the vibration of the latter, while the roof prevents wave breaking phenomena and introduces an essentially linear response. This creates a dynamic behavior that resembles other types of linear Tuned Mass dampers (TMDs). This investigation extends previous work of the authors to consider TLDs-FR with arbitrary tank cross-sections, whereas it additionally offers new insights on a variety of topics. In particular, the relationship between the tank geometry and the resultant vibratory characteristics is examined in detail, including the impact of the roof on these characteristics. An efficient mapping between these two is also developed, utilizing Kriging metamodeling concepts, to support the TLD-FR design. It is demonstrated that the overall behavior can be modeled through introduction of only four variables: the liquid mass, the frequency and damping ratio of the fundamental sloshing mode of the TLD-FR, and the efficiency index, which is related to the portion of the total mass that participates in this mode. Comparisons between TLDs-FR and other types of mass dampers are established through the use of the latter index. A design example is presented considering the dynamic response of a structure under stationary excitation. It is illustrated in this example that for complex tank cross-sectional geometries there exists a manifold of tank configurations leading to the same primary vibratory characteristics and therefore same efficiency of the TLD-FR. Considerations about excessive displacements of the roof can be then incorporated to indicate preference towards some of these

  15. Stormwater runoff mitigation and nutrient leaching from a green roof designed to attract native pollinating insects

    NASA Astrophysics Data System (ADS)

    Fogarty, S.; Grogan, D. S.; Hale, S. R.

    2013-12-01

    A green roof is typically installed for one of two reasons: to mitigate the 'urban heat island' effect, reducing ambient temperatures and creating energy savings, or to reduce both the quantity and intensity of stormwater runoff, which is a major cause of river erosion and eutrophication. The study of green roofs in the United States has focused on commercial systems that use a proprietary expanded shale or clay substrate, along with succulent desert plants (mainly Sedum species). The green roof has the potential not only to provide thermal insulation and reduce storm runoff, but also to reclaim some of the natural habitat that has been lost to the built environment. Of special importance is the loss of habitat for pollinating insects, particularly native bees, which have been in decline for at least two decades. These pollinators are essential for crop production and for the reproduction of at least 65% of wild plants globally. Our study involves the installation of a small (4ft by 4ft), self-designed green roof system built with readily available components from a hardware store. The garden will be filled with a soilless potting mix, combined with 15% compost, and planted with grasses and wildflowers native to the Seacoast, New Hampshire region. Some of the plant species are used by bees for nesting materials, while others provide food in the form of nectar, pollen, and seeds for bees, butterflies, hummingbirds, and granivorous birds. We monitor precipitation on the roof and runoff from the garden on a per storm basis, and test grab samples of runoff for dissolved organic nitrogen and phosphorous. Runoff and nutrient concentration results are compared to a non-vegetated roof surface, and a proprietary Green Grid green roof system. This project is designed to address three main questions of interest: 1) Can these native plant species, which potentially provide greater ecosystem services than Sedum spp. in the form of food and habitat, survive in the conditions on

  16. Investigating Appropriate Sampling Design for Estimating Above-Ground Biomass in Bruneian Lowland Mixed Dipterocarp Forest

    NASA Astrophysics Data System (ADS)

    Lee, S.; Lee, D.; Abu Salim, K.; Yun, H. M.; Han, S.; Lee, W. K.; Davies, S. J.; Son, Y.

    2014-12-01

    Mixed tropical forest structure is highly heterogeneous unlike plantation or mixed temperate forest structure, and therefore, different sampling approaches are required. However, the appropriate sampling design for estimating the above-ground biomass (AGB) in Bruneian lowland mixed dipterocarp forest (MDF) has not yet been fully clarified. The aim of this study was to provide supportive information in sampling design for Bruneian forest carbon inventory. The study site was located at Kuala Belalong lowland MDF, which is part of the Ulu Tembulong National Park, Brunei Darussalam. Six 60 m × 60 m quadrats were established, separated by a distance of approximately 100 m and each was subdivided into quadrats of 10 m × 10 m, at an elevation between 200 and 300 m above sea level. At each plot all free-standing trees with diameter at breast height (dbh) ≥ 1 cm were measured. The AGB for all trees with dbh ≥ 10 cm was estimated by allometric models. In order to analyze changes in the diameter-dependent parameters used for estimating the AGB, different quadrat areas, ranging from 10 m × 10 m to 60 m × 60 m, were used across the study area, starting at the South-West end and moving towards the North-East end. The derived result was as follows: (a) Big trees (dbh ≥ 70 cm) with sparse distribution have remarkable contribution to the total AGB in Bruneian lowland MDF, and therefore, special consideration is required when estimating the AGB of big trees. Stem number of trees with dbh ≥ 70 cm comprised only 2.7% of all trees with dbh ≥ 10 cm, but 38.5% of the total AGB. (b) For estimating the AGB of big trees at the given acceptable limit of precision (p), it is more efficient to use large quadrats than to use small quadrats, because the total sampling area decreases with the former. Our result showed that 239 20 m × 20 m quadrats (9.6 ha in total) were required, while 15 60 m × 60 m quadrats (5.4 ha in total) were required when estimating the AGB of the trees

  17. Quality Control through Design and Process: Gambrel Roof Truss Challenge

    ERIC Educational Resources Information Center

    Ward, Dell; Jones, James

    2011-01-01

    Customers determine whether a product fulfills their needs or satisfies them. "Quality control", then, is the process of finding out what the customer wants, along with designing, producing, delivering, and servicing the product--and ultimately satisfying the customer's expectations. For many years, people considered a product to be of good…

  18. Quality Control through Design and Process: Gambrel Roof Truss Challenge

    ERIC Educational Resources Information Center

    Ward, Dell; Jones, James

    2011-01-01

    Customers determine whether a product fulfills their needs or satisfies them. "Quality control", then, is the process of finding out what the customer wants, along with designing, producing, delivering, and servicing the product--and ultimately satisfying the customer's expectations. For many years, people considered a product to be of good…

  19. The case for using a sacrificial layer of absorbent insulation in the design of flat and low-sloped roofing

    NASA Astrophysics Data System (ADS)

    Stockton, Gregory R.

    2013-05-01

    Beginning about twenty-five years ago, there was a marked increase in the number of single-ply membrane roof designs used to cover and waterproof flat and low-sloped building roofs. Over the past ten years, there has been a substantial increase in the number of installations of white and more reflective single-ply roof systems, mostly using high density cellular foam insulation in the substrate for insulation. A major factor in the increase in the popularity of these highly insulated and more reflective roof systems is the fact that many governments began offering incentives for building owners to use reflective coverings and better insulated roofs. Now, owing to the energy efficient requirements for the design and construction of new buildings put forth in ASHRAE Standard 90.1, "Energy Standard for Buildings Except Low-Rise Residential Buildings" and the world's apparent desire to be "green" (or at least appear to be), more and more roof designs will include these reflective single-ply membranes, which use the cellular foam insulation boards to meet these requirements. Using a lower density traditional insulation will mean that the roof will have to be very thick to comply, increasing the costs of installation. High density cellular foams do not absorb water until time, vapor pressure drive, UV and thermal shock break down the foam and it becomes more absorbent. This could be 5-7 years or longer, depending on the roof construction and other factors. This means that any water that enters the roof through a breach (leak) in the membrane goes straight into the building. This is not a good consequence since the failure mode of any roof is water entering the building. Keeping the water out of the building is the purpose of the waterproofing layer. This paper reviews the techniques of moisture testing on building roofs and infrared (IR) thermography, and puts forth the idea and reasoning behind having a sacrificial layer of very absorbent insulation installed in every

  20. Design and development of green roof substrate to improve runoff water quality: plant growth experiments and adsorption.

    PubMed

    Vijayaraghavan, K; Raja, Franklin D

    2014-10-15

    Many studies worldwide have investigated the potential benefits achievable by transforming brown roofs of buildings to green roofs. However, little literature examined the runoff quality/sorption ability of green roofs. As the green roof substrate is the main component to alter the quality of runoff, this investigation raises the possibility of using a mixture of low-cost inorganic materials to develop a green roof substrate. The tested materials include exfoliated vermiculite, expanded perlite, crushed brick and sand along with organic component (coco-peat). Detailed physical and chemical analyses revealed that each of these materials possesses different characteristics and hence a mix of these materials was desirable to develop an optimal green roof substrate. Using factorial design, 18 different substrate mixes were prepared and detailed examination indicated that mix-12 exhibited desirable characteristics of green roof substrate with low bulk density (431 kg/m(3)), high water holding capacity (39.4%), air filled porosity (19.5%), and hydraulic conductivity (4570 mm/h). The substrate mix also provided maximum support to Portulaca grandiflora (380% total biomass increment) over one month of growth. To explore the leaching characteristics and sorption capacity of developed green roof substrate, a down-flow packed column arrangement was employed. High conductivity and total dissolved solids along with light metal ions (Na, K, Ca and Mg) were observed in the leachates during initial stages of column operation; however the concentration of ions ceased during the final stages of operation (600 min). Experiments with metal-spiked deionized water revealed that green roof substrate possess high sorption capacity towards various heavy metal ions (Al, Fe, Cr, Cu, Ni, Pb, Zn and Cd). Thus the developed growth substrate possesses desirable characteristics for green roofs along with high sorption capacity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Interdisciplinary design study of a high-rise integrated roof wind energy system

    NASA Astrophysics Data System (ADS)

    Dekker, R. W. A.; Ferraro, R. M.; Suma, A. B.; Moonen, S. P. G.

    2012-10-01

    Today's market in micro-wind turbines is in constant development introducing more efficient solutions for the future. Besides the private use of tower supported turbines, opportunities to integrate wind turbines in the built environment arise. The Integrated Roof Wind Energy System (IRWES) presented in this work is a modular roof structure integrated on top of existing or new buildings. IRWES is build up by an axial array of skewed shaped funnels used for both wind inlet and outlet. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a Vertical Axis Wind Turbine (VAWT) in the center-top of the roof unit for the generation of a relatively high amount of energy. The scope of this research aims to make an optimized structural design of IRWES to be placed on top of the Vertigo building in Eindhoven; analysis of the structural performance; and impact to the existing structure by means of Finite Element Modeling (FEM). Results show that the obvious impact of wind pressure to the structural design is easily supported in different configurations of fairly simple lightweight structures. In particular, the weight addition to existing buildings remains minimal.

  2. A Modified Coal Mine Roof Rating Classification System to Design Support Requirements in Coal Mines

    NASA Astrophysics Data System (ADS)

    Taheri, Abbas; Lee, Yongha; Medina, Mario Andres Guardado

    2017-10-01

    The coal mine roof rating (CMRR) classification system has been applied in a number of coal mines worldwide including Australia. However, the current system cannot be used directly to design support measures in underground mines. Two case studies, the Eliza Hill project in Australia and Tabas coal mine in Iran were analyzed to assess the impact of various rock properties and gallery geometry on stability and to modify the CMRR classification system. Having considered the CMRR system as a working classification system, applicable information and related coal mine data were selected from the two case records. The CMRR value was evaluated and analysed by undertaking correlation between CMRR and factor of safety, followed by a parametric study based on various rock properties and gallery geometries. To improve the applicability of the current system, the CMRR system was then modified by adding additional parameters, namely, the width of roof span and the density of overburden rock. Consequently, based on the modified CMRR system (mCMRR) roof support requirements were recommended to select the suitable rock bolting system including length and spacing of rock bolt. Numerical modelling were then undertaken to verify the support requirements recommended. The support requirements recommended by the mCMRR were found to be relatively identical with numerical analysis results. Support systems proposed by mCMRR can assist mining engineers to assess the stability of underground coal mines or verify the results of other design tools.

  3. A Modified Coal Mine Roof Rating Classification System to Design Support Requirements in Coal Mines

    NASA Astrophysics Data System (ADS)

    Taheri, Abbas; Lee, Yongha; Medina, Mario Andres Guardado

    2017-01-01

    The coal mine roof rating (CMRR) classification system has been applied in a number of coal mines worldwide including Australia. However, the current system cannot be used directly to design support measures in underground mines. Two case studies, the Eliza Hill project in Australia and Tabas coal mine in Iran were analyzed to assess the impact of various rock properties and gallery geometry on stability and to modify the CMRR classification system. Having considered the CMRR system as a working classification system, applicable information and related coal mine data were selected from the two case records. The CMRR value was evaluated and analysed by undertaking correlation between CMRR and factor of safety, followed by a parametric study based on various rock properties and gallery geometries. To improve the applicability of the current system, the CMRR system was then modified by adding additional parameters, namely, the width of roof span and the density of overburden rock. Consequently, based on the modified CMRR system (mCMRR) roof support requirements were recommended to select the suitable rock bolting system including length and spacing of rock bolt. Numerical modelling were then undertaken to verify the support requirements recommended. The support requirements recommended by the mCMRR were found to be relatively identical with numerical analysis results. Support systems proposed by mCMRR can assist mining engineers to assess the stability of underground coal mines or verify the results of other design tools.

  4. Vibration Reduction Design of Equipment on the Low-floor Tramcar’s Roof

    NASA Astrophysics Data System (ADS)

    Feng, Zunwei; He, Binbin

    2017-06-01

    In order to suppress the influence of the excitation source of the roof equipment on the vibration of the vehicle body, a vibration reduction design scheme based on rigid and flexible coupling dynamic model is proposed. The finite element model is established, and the finite element analysis is used to calculate the car body mode. The dynamic model is established and the vibration mode is analyzed. The frequency range of the equipment is determined by the analysis result which is based on the vibration reduction theory. The rigid and flexible coupling dynamics model is established to optimize the equipment support frequency. The results show that when the frequency of the equipment is 10 Hz, the support point can obviously eliminate the vibration effect. The dynamic deflection of the equipment is less than 2 mm, and the vibration performance satisfies the design requirements.

  5. Design of self-cleaning TiO2 coating on clay roofing tiles

    NASA Astrophysics Data System (ADS)

    Hadnadjev, Milica; Ranogajec, Jonjaua; Petrovic, Snezana; Markov, Sinisa; Ducman, Vilma; Marinkovic-Neducin, Radmila

    2010-07-01

    The phenomenon of heterogeneous photocatalysis takes place in the degradation process of many organic contaminants on solid surfaces. Photocatalysis is based on the excitation of the semiconductor by irradiation with supraband gap photons and the migration of electron-hole pairs to the surface of the photocatalysts, leading to the reaction of the holes with adsorbed H2O and OH- to form hydroxyl radicals. Due to the stability and photosensitivity of TiO2 semiconductors, this system is well studied and is of great interest from an ecological and industrial point of view for use in the field of building materials. Clay roofing tiles, due to their long-term exploitation, are subject to physical, chemical and biological degradation that leads to deterioration. Ceramic systems have a high percentage of total porosity and considering their non-tolerance of organic coating, the use of surface active materials (SAM) that induce porosity in TiO2 coatings is of vital significance. Photocatalytic coatings applied on clay roofing tiles under industrial conditions were designed by varying the quantity of TiO2 (mass/cm2) on the tile surface (thin and thick TiO2 layer). The positive changes in specific surface area and mesopore structure of the designed coatings were made by the addition of PEG 600 as a surface active material. It was shown that a thin photocatalytic layer (0.399 mg suspension/cm2 tile surface), applied onto ceramic tiles under industrial conditions, had better photocatalytic activity in methylene blue decomposition, hydrophilicity and antimicrobial activity than a thick photocatalytic coating (0.885 mg suspension/cm2).

  6. Roofing: Workbook and Tests. Built-up Roofing.

    ERIC Educational Resources Information Center

    Klingensmith, Robert, Ed.

    Designed for use in roofing apprenticeship classes, this workbook contains eight units on skills used in built-up roofing, a listing of instructional materials, a glossary, and the text of Labor Code Article 30, Construction Safety Orders, "Roofing Operations and Equipment." Each instructional unit includes a listing of performance statements and…

  7. Roof Roundup.

    ERIC Educational Resources Information Center

    American School and University, 1984

    1984-01-01

    The roof management program at the University of Wyoming involved a consulting firm that provided a computer analysis of the condition of each roof on campus and trained university personnel to act as inspectors in the future. (MLF)

  8. Moisture design to improve durability of low-slope roofing systems

    SciTech Connect

    Desjarlais, A.; Byars, N.

    1996-12-31

    The roofing industry has traditionally held that moisture control in low-slope roofing comprises two independent elements: (1) provide a waterproof exterior covering (or membrane) to protect the low-slope roof from external sources of moisture and (2) perform a condensation calculation to determine if a vapor retarder is required to protect a roof system from internal moisture sources. The first criterion is assumed to be satisfied if a membrane system is specified; in reality, all membrane systems eventually fail, and existing moisture control strategies offer no mechanism for analyzing the inevitable failure. The means of assessing the second criterion, the need for a vapor retarder, has evolved in recent years. The criteria have become more liberal with time because it has been observed that roofing systems installed in a geographic area in which the old criteria required a vapor retarder, have performed well without one.

  9. Impacts of Sample Design on Estimation of Aboveground Biomass: Implications for the Assimilation of Lidar and Forest Inventory Data

    NASA Astrophysics Data System (ADS)

    Duffy, P.; Keller, M. M.; Morton, D. C.; Schimel, D.

    2015-12-01

    The availability of lidar data that can be used to characterize forest structure and estimate aboveground biomass (AGB) is rapidly increasing. When lidar data are considered in conjunction with forest inventory data to estimate AGB, the order of acquisition for these data products may impact the quality of the resulting estimates. In this work, we address this question in the context of uncertainty reduction with respect to estimation of AGB in a degraded forest in Paragominas, Brazil. We have developed a simulation framework that quantitatively assesses the uncertainty associated with estimation of AGB for different sampling strategies that combine forest inventory and lidar data. We utilize a Bayesian hierarchical modeling (BHM) data assimilation framework to combine information from the forest inventory and lidar data products into a higher order data product of AGB. Spatially explicit realizations of AGB are generated under different sampling strategies. Sampling strategies are assessed using the distributional properties of the assimilated higher order data product in the context of uncertainty reduction. We consider both spatially explicit maps of uncertainty as well as the standard deviation of the posterior predictive distributions of AGB as endpoints for the quantification of uncertainty. This framework allows for the explicit characterization of important sources of uncertainty. Our results show that a significant reduction in the uncertainty associated with estimation of AGB can be realized when design optimization is utilized in this context.

  10. 49 CFR 195.132 - Design and construction of aboveground breakout tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) and with internal vapor space pressures that are approximately atmospheric must be designed and... approximating atmospheric pressures (i.e., internal vapor space pressures not greater than 2.5 psig (17.2 kPa... to withstand the internal pressure produced by the hazardous liquid to be stored therein and...

  11. 49 CFR 195.132 - Design and construction of aboveground breakout tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) and with internal vapor space pressures that are approximately atmospheric must be designed and... approximating atmospheric pressures (i.e., internal vapor space pressures not greater than 2.5 psig (17.2 kPa... to withstand the internal pressure produced by the hazardous liquid to be stored therein and...

  12. 49 CFR 195.132 - Design and construction of aboveground breakout tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) and with internal vapor space pressures that are approximately atmospheric must be designed and... approximating atmospheric pressures (i.e., internal vapor space pressures not greater than 2.5 psig (17.2 kPa... to withstand the internal pressure produced by the hazardous liquid to be stored therein and...

  13. 49 CFR 195.132 - Design and construction of aboveground breakout tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) and with internal vapor space pressures that are approximately atmospheric must be designed and... approximating atmospheric pressures (i.e., internal vapor space pressures not greater than 2.5 psig (17.2 kPa... to withstand the internal pressure produced by the hazardous liquid to be stored therein and...

  14. 49 CFR 195.132 - Design and construction of aboveground breakout tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) and with internal vapor space pressures that are approximately atmospheric must be designed and... approximating atmospheric pressures (i.e., internal vapor space pressures not greater than 2.5 psig (17.2 kPa... to withstand the internal pressure produced by the hazardous liquid to be stored therein and...

  15. Case study: design, operation, maintenance and water quality management of sustainable storm water ponds for roof runoff.

    PubMed

    Scholz, Miklas

    2004-12-01

    The purpose of this case study was to optimise design, operation and maintenance guidelines, and to assess the water treatment potential of a storm water pond system after 15 months of operation. The system was based on a combined silt trap, attenuation pond and vegetated infiltration basin. This combination was used as the basis for construction of a roof water runoff system from a single domestic property. United Kingdom Building Research Establishment and Construction Industry Research and Information Association, and German Association for Water, Wastewater and Waste design guidelines were tested. These design guidelines failed because they did not consider local conditions. The infiltration function for the infiltration basin was logarithmic. Algal control techniques were successfully applied, and treatment of rainwater runoff from roofs was found to be largely unnecessary for recycling (e.g., watering plants). However, seasonal and diurnal variations of biochemical oxygen demand, dissolved oxygen and pH were recorded.

  16. Seismic design repair and retrofit strategies for steel roof deck diaphragms

    NASA Astrophysics Data System (ADS)

    Franquet, John-Edward

    Structural engineers will often rely on the roof diaphragm to transfer lateral seismic loads to the bracing system of single-storey structures. The implementation of capacity-based design in the NBCC 2005 has caused an increase in the diaphragm design load due to the need to use the probable capacity of the bracing system, thus resulting in thicker decks, closer connector patterns and higher construction costs. Previous studies have shown that accounting for the in-plane flexibility of the diaphragm when calculating the overall building period can result in lower seismic forces and a more cost-efficient design. However, recent studies estimating the fundamental period of single storey structures using ambient vibration testing showed that the in-situ approximation was much shorter than that obtained using analytical means. The difference lies partially in the diaphragm stiffness characteristics which have been shown to decrease under increasing excitation amplitude. Using the diaphragm as the energy-dissipating element in the seismic force resisting system has also been investigated as this would take advantage of the diaphragm's ductility and limited overstrength; thus, lower capacity based seismic forces would result. An experimental program on 21.0m by 7.31m diaphragm test specimens was carried out so as to investigate the dynamic properties of diaphragms including the stiffness, ductility and capacity. The specimens consisted of 20 and 22 gauge panels with nailed frame fasteners and screwed sidelap connections as well a welded and button-punch specimen. Repair strategies for diaphragms that have previously undergone inelastic deformations were devised in an attempt to restitute the original stiffness and strength and were then experimentally evaluated. Strength and stiffness experimental estimations are compared with those predicted with the Steel Deck Institute (SDI) method. A building design comparative study was also completed. This study looks at the

  17. Roof bolting equipment & technology

    SciTech Connect

    Fiscor, S.

    2009-04-15

    Technology provides an evaluator path to improvement for roof bolting machines. Bucyrus offers three different roof bolts models for various mining conditions. The LRB-15 AR is a single-arm boiler recommended for ranges of 32 inches and above; the dual-arm RB2-52A for ranges of 42 inches and above; and the dual-arm RB2-88A for ranges of 54 inches and above. Design features are discussed in the article. Developments in roof bolting technology by Joy Mining Machinery are reported. 4 photos.

  18. Sustainable roofs with real energy savings

    SciTech Connect

    Christian, J.E.; Petrie, T.W.

    1996-12-31

    This paper addresses the general concept of sustainability and relates it to the building owner`s selection of a low-slope roof. It offers a list of performance features of sustainable roofs. Experiences and data relevant to these features for four unique roofs are then presented which include: self-drying systems, low total equivalent warming foam insulation, roof coatings and green roofs. The paper concludes with a list of sustainable roofing features worth considering for a low-slope roof investment. Building owners and community developers are showing more interest in investing in sustainability. The potential exists to design, construct, and maintain roofs that last twice as long and reduce the building space heating and cooling energy loads resulting from the roof by 50% (based on the current predominant design of a 10-year life and a single layer of 1 to 2 in. (2.5 to 5.1 cm) of insulation). The opportunity to provide better low-slope roofs and sell more roof maintenance service is escalating. The general trend of outsourcing services could lead to roofing companies` owning the roofs they install while the traditional building owner owns the rest of the building. Such a situation would have a very desirable potential to internalize the costs of poor roof maintenance practices and high roof waste disposal costs, and to offer a profit for installing roofs that are more sustainable. 14 refs., 12 figs.

  19. Prolong Your Roof's Performance: Roof Asset Management.

    ERIC Educational Resources Information Center

    Teitsma, Jerry

    2001-01-01

    Discusses the roof asset management process for maintaining a roof system's integrity and value in a cost-effective manner. Included is a breakdown of roofing surface characteristics for multiply and single ply roofing systems. (GR)

  20. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2003-04-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. More field tests have been performed. A trendline analysis method has been developed. This method would improve the accuracy in detecting the locations of fractures and in determining the rock strength.

  1. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2003-01-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. Additional field tests have been performed. It is found that the drilling power can be used as a supplementary method for detecting voids/fractures and rock interfaces.

  2. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2002-10-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. Additional field tests have been performed in this quarter. The development of the data interpretation methodology and other related tasks are still continuing.

  3. 49 CFR 195.405 - Protection against ignitions and safe access/egress involving floating roofs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .../egress involving floating roofs. 195.405 Section 195.405 Transportation Other Regulations Relating to....405 Protection against ignitions and safe access/egress involving floating roofs. (a) After October 2... floating roofs of in-service aboveground breakout tanks to perform inspection, service, maintenance or...

  4. 49 CFR 195.405 - Protection against ignitions and safe access/egress involving floating roofs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .../egress involving floating roofs. 195.405 Section 195.405 Transportation Other Regulations Relating to....405 Protection against ignitions and safe access/egress involving floating roofs. (a) After October 2... floating roofs of in-service aboveground breakout tanks to perform inspection, service, maintenance or...

  5. 49 CFR 195.405 - Protection against ignitions and safe access/egress involving floating roofs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .../egress involving floating roofs. 195.405 Section 195.405 Transportation Other Regulations Relating to....405 Protection against ignitions and safe access/egress involving floating roofs. (a) After October 2... floating roofs of in-service aboveground breakout tanks to perform inspection, service, maintenance or...

  6. 49 CFR 195.405 - Protection against ignitions and safe access/egress involving floating roofs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .../egress involving floating roofs. 195.405 Section 195.405 Transportation Other Regulations Relating to....405 Protection against ignitions and safe access/egress involving floating roofs. (a) After October 2... floating roofs of in-service aboveground breakout tanks to perform inspection, service, maintenance or...

  7. 49 CFR 195.405 - Protection against ignitions and safe access/egress involving floating roofs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .../egress involving floating roofs. 195.405 Section 195.405 Transportation Other Regulations Relating to....405 Protection against ignitions and safe access/egress involving floating roofs. (a) After October 2... floating roofs of in-service aboveground breakout tanks to perform inspection, service, maintenance or...

  8. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Fixed roof with an internal floating... internal floating roof (IFR). (a) IFR design requirements. The owner or operator who elects to control storage vessel regulated material emissions by using a fixed roof and an internal floating roof shall...

  9. Carbon sequestration potential of extensive green roofs.

    PubMed

    Getter, Kristin L; Rowe, D Bradley; Robertson, G Philip; Cregg, Bert M; Andresen, Jeffrey A

    2009-10-01

    Two studies were conducted with the objective of quantifying the carbon storage potential of extensive green roofs. The first was performed on eight roofs in Michigan and four roofs in Maryland, ranging from 1 to 6 years in age. All 12 green roofs were composed primarily of Sedum species, and substrate depths ranged from 2.5 to 12.7 cm. Aboveground plant material was harvested in the fall of 2006. On average, these roofs stored 162 g C x m(-2) in aboveground biomass. The second study was conducted on a roof in East Lansing, MI. Twenty plots were established on 21 April 2007 with a substrate depth of 6.0 cm. In addition to a substrate only control, the other plots were sown with a single species of Sedum (S. acre, S. album, S. kamtshaticum, or S. spurium). Species and substrate depth represent typical extensive green roofs in the United States. Plant material and substrate were harvested seven times across two growing seasons. Results at the end of the second year showed that aboveground plant material storage varied by species, ranging from 64 g C x m(-2) (S. acre) to 239 g C x m(-2) (S. album), with an average of 168 g C x m(-2). Belowground biomass ranged from 37 g C x m(-2) (S. acre) to 185 g C x m(-2) (S. kamtschaticum) and averaged 107 g C x m(-2). Substrate carbon content averaged 913 g C x m(-2), with no species effect, which represents a sequestration rate of 100 g C x m(-2) over the 2 years of this study. The entire extensive green roof system sequestered 375 g C x m(-2) in above- and belowground biomass and substrate organic matter.

  10. Green Roofs

    SciTech Connect

    2004-08-01

    A New Technology Demonstration Publication Green roofs can improve the energy performance of federal buildings, help manage stormwater, reduce airborne emissions, and mitigate the effects of urban heat islands.

  11. Photovoltaic Roofs

    NASA Technical Reports Server (NTRS)

    Drummond, R. W., Jr.; Shepard, N. F., Jr.

    1984-01-01

    Solar cells perform two functions: waterproofing roof and generating electricity. Sections through horizontal and slanting joints show overlapping modules sealed by L-section rubber strips and side-by-side modules sealed by P-section strips. Water seeping through seals of slanting joints drains along channels. Rooftop photovoltaic array used watertight south facing roof, replacing shingles, tar, and gravel. Concept reduces cost of residential solar-cell array.

  12. Evaluations of bit sleeve and twisted-body bit designs for controlling roof bolter dust

    PubMed Central

    Beck, T.W.

    2015-01-01

    Drilling into coal mine roof strata to install roof bolts has the potential to release substantial quantities of respirable dust. Due to the proximity of drill holes to the breathing zone of roof bolting personnel, dust escaping the holes and avoiding capture by the dust collection system pose a potential respiratory health risk. Controls are available to complement the typical dry vacuum collection system and minimize harmful exposures during the initial phase of drilling. This paper examines the use of a bit sleeve in combination with a dust-hog-type bit to improve dust extraction during the critical initial phase of drilling. A twisted-body drill bit is also evaluated to determine the quantity of dust liberated in comparison with the dust-hog-type bit. Based on the results of our laboratory tests, the bit sleeve may reduce dust emissions by one-half during the initial phase of drilling before the drill bit is fully enclosed by the drill hole. Because collaring is responsible for the largest dust liberations, overall dust emission can also be substantially reduced. The use of a twisted-body bit has minimal improvement on dust capture compared with the commonly used dust-hog-type bit. PMID:26257435

  13. Contributions to the design of rainwater harvesting systems in buildings with green roofs in a Mediterranean climate.

    PubMed

    Monteiro, Cristina M; Calheiros, Cristina S C; Pimentel-Rodrigues, Carla; Silva-Afonso, Armando; Castro, Paula M L

    2016-01-01

    Green roofs (GRs) are becoming a trend in urban areas, favouring thermal performance of buildings, promoting removal of atmospheric pollutants, and acting as possible water collection spots. Rainwater harvesting systems in buildings can also contribute to the management of stormwater runoff reducing flood peaks. These technologies should be enhanced in Mediterranean countries where water scarcity is increasing and the occurrence of extreme events is becoming very significant, as a result of climate change. An extensive pilot GR with three aromatic plant species, Satureja montana, Thymus caespititius and Thymus pseudolanuginosus, designed to study several parameters affecting rainwater runoff, has been in operation for 12 months. Physico-chemical analyses of roof water runoff (turbidity, pH, conductivity, NH4(+), NO3(-), PO4(3-), chemical oxygen demand) have shown that water was of sufficient quality for non-potable uses in buildings, such as toilet flushing. An innovative approach allowed for the development of an expression to predict a 'monthly runoff coefficient' of the GR system. This parameter is essential when planning and designing GRs combined with rainwater harvesting systems in a Mediterranean climate. This study is a contribution to improving the basis for the design of rainwater harvesting systems in buildings with extensive GRs under a Mediterranean climate.

  14. Evaluation of Roof Bolting Requirements Based on In-Mine Roof Bolter Drilling

    SciTech Connect

    Syd S. Peng

    2005-10-01

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on this information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. For the prediction of roof geology and stability condition in real time, a micro processor was used and a program developed to monitor and record the drilling parameters of roof bolter. These parameters include feed pressure, feed flow (penetration rate), rotation pressure, rotation rate, vacuum pressure, oil temperature of hydraulic circuit, and signals for controlling machine. From the results of a series of laboratory and underground tests so far, feed pressure is found to be a good indicator for identifying the voids/fractures and estimating the roof rock strength. The method for determining quantitatively the location and the size of void/fracture and estimating the roof rock strength from the drilling parameters of roof bolter was developed. Also, a set of computational rules has been developed for in-mine roof using measured roof drilling parameters and implemented in MRGIS (Mine Roof Geology Information System), a software package developed to allow mine engineers to make use of the large amount of roof drilling parameters for predicting roof geology properties automatically. For the development of roof bolting criteria, finite element models were developed for tensioned and fully grouted bolting

  15. Roof Plans: Section "CC", Roof Plan; Roof Framing Plans: Section ...

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

    Roof Plans: Section "C-C", Roof Plan; Roof Framing Plans: Section "C-C", Section "D-D"; Roof Framing Sections: Cross Section "G-G", Cross Section "H-H" - Fort Washington, Fort Washington Light, Northeast side of Potomac River at Fort Washington Park, Fort Washington, Prince George's County, MD

  16. Roof Rockmass Characterization in an Illinois Underground Coal Mine

    NASA Astrophysics Data System (ADS)

    Osouli, Abdolreza; Shafii, Iman

    2016-08-01

    Among all United States underground coal fields, those in Illinois have the highest rate of roof fall events due to their weak and severely moisture sensitive roof rock units. Rockmass characterization is the key initial step in designing safe and economical roof control measures in underground coal mines. In this study, a performance-based roof rockmass characterization is investigated. The geologic conditions as well as underground mine geographic specifications, roof fall analysis, mining method, utilized supplemental roof control measures, and geotechnical properties of roof rock units were considered to link the roof performance to rockmass characterization. The coal mine roof rating (CMRR) rockmass characterization method was used to evaluate the roof conditions and roof support design for an underground coal mine located in the Illinois Coal Basin. The results of several mine visit mappings, laboratory test results, and geotechnical issues and concerns are presented and discussed. The roof support designs are analyzed based on the rockmass characterization and are compared with the observed performance. This study shows that (1) CMRR index is a reasonable method for characterizing roof rockmass; (2) moisture sensitivity and bedding strengths in the horizontal direction are essential parameters for roof support design in mines with weak roof conditions; and (3) the applicability of the analysis of roof bolt system for roof support design of the studied mine is questionable.

  17. Choosing the Right Roof.

    ERIC Educational Resources Information Center

    Evans, Jeff

    1999-01-01

    Offers tips for selecting roofing products for new or renovated buildings. Examines various site-specific design parameters such as building life, climatic exposure, water drainage, traffic resistance, and insurer's requirements. Notes points to address in preparing clear, detailed, and well-conceived specifications. (GR)

  18. Separating Drought Effects from Roof Artifacts on Ecosystem Processes in a Grassland Drought Experiment

    PubMed Central

    Vogel, Anja; Fester, Thomas; Eisenhauer, Nico; Scherer-Lorenzen, Michael; Schmid, Bernhard; Weisser, Wolfgang W.; Weigelt, Alexandra

    2013-01-01

    1 Given the predictions of increased drought probabilities under various climate change scenarios, there have been numerous experimental field studies simulating drought using transparent roofs in different ecosystems and regions. Such roofs may, however, have unknown side effects, called artifacts, on the measured variables potentially confounding the experimental results. A roofed control allows the quantification of potential artifacts, which is lacking in most experiments. 2 We conducted a drought experiment in experimental grasslands to study artifacts of transparent roofs and the resulting effects of artifacts on ecosystems relative to drought on three response variables (aboveground biomass, litter decomposition and plant metabolite profiles). We established three drought treatments, using (1) transparent roofs to exclude rainfall, (2) an unroofed control treatment receiving natural rainfall and (3) a roofed control, nested in the drought treatment but with rain water reapplied according to ambient conditions. 3 Roofs had a slight impact on air (+0.14°C during night) and soil temperatures (−0.45°C on warm days, +0.25°C on cold nights), while photosynthetically active radiation was decreased significantly (−16%). Aboveground plant community biomass was reduced in the drought treatment (−41%), but there was no significant difference between the roofed and unroofed control, i.e., there were no measurable roof artifact effects. 4 Compared to the unroofed control, litter decomposition was decreased significantly both in the drought treatment (−26%) and in the roofed control treatment (−18%), suggesting artifact effects of the transparent roofs. Moreover, aboveground metabolite profiles in the model plant species Medicago x varia were different from the unroofed control in both the drought and roofed control treatments, and roof artifact effects were of comparable magnitude as drought effects. 5 Our results stress the need for roofed control

  19. Understanding Roofing Systems.

    ERIC Educational Resources Information Center

    Michelsen, Ted

    2001-01-01

    Reviews the various types of multi- and single-ply roofing commonly used today in educational facilities. Roofing types described involve built-up systems, modified bitumen systems; ethylene propylene diene terpolymer roofs; and roofs of thermoplastic, metal, and foam. A description of the Roofing Industry Educational Institute is included. (GR)

  20. Understanding Roofing Systems.

    ERIC Educational Resources Information Center

    Michelsen, Ted

    2001-01-01

    Reviews the various types of multi- and single-ply roofing commonly used today in educational facilities. Roofing types described involve built-up systems, modified bitumen systems; ethylene propylene diene terpolymer roofs; and roofs of thermoplastic, metal, and foam. A description of the Roofing Industry Educational Institute is included. (GR)

  1. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2001-10-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. The retrofitting works for a dedicated roof bolter for this research has been completed. The laboratory tests performed using this machine on simulated roof blocks have been conducted. The analysis performed on the testing data showed promising signs to detect the rock interface, fractures, as well as the rock types. The other tasks were progressing as planned.

  2. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2001-07-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. In this quarter, retrofitting work to build a dedicated roof bolter for this research has been started. A number of numerical methods have been developed to improve the quality of and to analyze the collected drilling parameters. Finite element modeling of roof bolting mechanism is continuing.

  3. Green roofs: potential at LANL

    SciTech Connect

    Pacheco, Elena M

    2009-01-01

    strokes, heat exhaustion, and pollution that can agitate the respiratory system. The most significant savings associated with green roofs is in the reduction of cooling demands due to the green roof's thermal mass and their insulating properties. Unlike a conventional roof system, a green roof does not absorb solar radiation and transfer that heat into the interior of a building. Instead the vegetation acts as a shade barrier and stabilizes the roof temperature so that interior temperatures remain comfortable for the occupants. Consequently there is less of a demand for air conditioning, and thus less money spent on energy. At LANL the potential of green roof systems has already been realized with the construction of the accessible green roof on the Otowi building. To further explore the possibilities and prospective benefits of green roofs though, the initial capital costs must be invested. Three buildings, TA-03-1698, TA-03-0502, and TA-53-0031 have all been identified as sound candidates for a green roof retrofit project. It is recommended that LANL proceed with further analysis of these projects and implementation of the green roofs. Furthermore, it is recommended that an urban forestry program be initiated to provide supplemental support to the environmental goals of green roofs. The obstacles barring green roof construction are most often budgetary and structural concerns. Given proper resources, however, the engineers and design professionals at LANL would surely succeed in the proper implementation of green roof systems so as to optimize their ecological and monetary benefits for the entire organization.

  4. Rules To Roof By.

    ERIC Educational Resources Information Center

    Hale, Olivia

    2002-01-01

    Advises schools on keeping roofs healthy, thereby saving costly repairs to both the roof and the entire building. Discusses inspections, preventive-maintenance programs, weather, and when to re-roof. (EV)

  5. Demonstration of Three Corrosion-Resistant Sustainable Roofing Systems

    DTIC Science & Technology

    2013-06-01

    sloped- roof conversion using standing-seam metal roofing system with heat-shedding coating, and (3) a fiber - glass -reinforced plastic (FRP) panel...the location to demonstrate (1) a heat-resistant metal shingle roofing sys- tem with above-sheathing ventilation (ASV), (2) a sloped- roof conversion...51 Appendix A: Roof Design Drawings for Buildings 8-3846 and 3-2631 (Stone- Coated Shingle System

  6. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2003-07-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. In this quarter, the field, theoretical and programming works have been performed toward achieving the research goals set in the proposal. The selected site and the field testing plan enabled us to test all three aspects of roof geological features. The development of the data interpretation methodologies and the geology mapping computer program have also been preceding well.

  7. Self drying roofs: What! No dripping!

    SciTech Connect

    Desjarlais, A.

    1995-12-31

    Many roofs are replaced because water accumulates in portions of the roofing system.These accumulations can cause dripping, accelerated membrane failure, poor thermal performance, the threat of structural decay, and the depreciation of building assets. Traditionally, the roofing industry has been concerned with controlling the inflow of water into the roof. An example of this strategy would be the development of a more reliable membrane. However, roof membranes inevitably leak. For this reason, the roof design strategy of the future must be concerned with controlling water outflow. The requirements of this type of roof system are described. Under normal operating conditions (no leaks), the total moisture content of a self-drying roof system shall not increase with time and condensation shall not occur under the membrane during winter uptake. Moisture vapor movement by convection must be eliminated and the flow of water by gravity through imperfections in the roof system must be controlled. After a leak has occurred, no condensation on the upper surface of the deck shall be tolerated and the water introduced by the leak must be dissipated to the building interior in a minimum amount of time. Finite difference computer modeling is used to demonstrate the effectiveness of the design. The impact of deck and insulation permeance, climate, leaks, and wintertime water uptake are simulated. A database of simulations is qualitatively described; this database will be used in future work to produce a simplified means of assessing the design parameters of a self-drying roof system.

  8. Design optimization in underground coal systems. Volume VIII. The roof truss: an analysis with applications to mine design. Final technical report

    SciTech Connect

    Not Available

    1981-02-28

    The purpose of this research effort was to optimize the application of the roof truss for use in supporting coal mine roofs. Model analysis using two-dimensinal, body-loaded, photoelastic models was supplemented with field data and testing. A detailed literature review was also undertaken. The detailed analysis of photoelastic models of roof trusses was pursued by varying a number of the truss parameters - center-span installation angles and blocking-point configuration. In obtaining reduced deflection, the best support was achieved employing an angle of installation of 90/sup 0/. However, due to roof failute considerations, the recommended angle of installation was 45/sup 0/. Blocking points were shown to have an effect on roof-support capacity as well as truss span, and field tests indicated that the installation of a roof truss actually raised the roof. Also, from field measurements, it was shown that all sections of the arch carried the same load. The use of the roof truss as a major support principle and device in underground coal mines was confined. The installation angle should be 45/sup 0/ in any specified roof span. Blocking is an essential part of the arch installation and should be carefully implemented to insure maximum efficiency of the arch. It was concluded that: the truss installation of 45/sup 0/ produces maximum benefit when the overall stability of the roof is considered; the two-dimensional, body-loaded photoelastic model may be used to analyze underground structures; in underground installations, all components of the roof truss structure sustain the same load; and uplift of the roof may be achieved during installation of the roof truss system.

  9. Design, Development, and Performance Evaluation of Solar Heating System for Disinfection of Domestic Roof-Harvested Rainwater.

    PubMed

    Akintola, O A; Sangodoyin, A Y

    2015-01-01

    A box-type solar heater was designed, constructed, and used to determine the effect of solar heating on quality of domestic roof-harvested rainwater (DRHRW). During testing, naturally contaminated DRHRW was harvested in Ibadan, Nigeria, and released into the system at 93.96 Lh(-1) (2.61 × 10(-5) m(3) s(-1)) in a continuous flow process. Water temperatures at inlet, within the heating chamber, and at outlet from the heating chamber and solar radiation were monitored at 10 min interval. Samples were collected at both inlet to and outlet from the heating chamber at 10 min interval for microbiological analysis. The highest plate stagnation temperature, under no-load condition, was 100°C. The solar water heater attained a maximum operational temperature of 75°C with 89.6 and 94.4% reduction in total viable count and total coliform count, respectively, while Escherichia coli and Staphylococcus aureus were completely eradicated at this temperature. The solar heater developed proved to be effective in enhancing potability of DRHRW in Ibadan, Nigeria. This may be an appropriate household water treatment technology for developing countries, hence, a way of resolving problem of low quality water for potable uses.

  10. Design, Development, and Performance Evaluation of Solar Heating System for Disinfection of Domestic Roof-Harvested Rainwater

    PubMed Central

    Sangodoyin, A. Y.

    2015-01-01

    A box-type solar heater was designed, constructed, and used to determine the effect of solar heating on quality of domestic roof-harvested rainwater (DRHRW). During testing, naturally contaminated DRHRW was harvested in Ibadan, Nigeria, and released into the system at 93.96 Lh−1 (2.61 × 10−5 m3 s−1) in a continuous flow process. Water temperatures at inlet, within the heating chamber, and at outlet from the heating chamber and solar radiation were monitored at 10 min interval. Samples were collected at both inlet to and outlet from the heating chamber at 10 min interval for microbiological analysis. The highest plate stagnation temperature, under no-load condition, was 100°C. The solar water heater attained a maximum operational temperature of 75°C with 89.6 and 94.4% reduction in total viable count and total coliform count, respectively, while Escherichia coli and Staphylococcus aureus were completely eradicated at this temperature. The solar heater developed proved to be effective in enhancing potability of DRHRW in Ibadan, Nigeria. This may be an appropriate household water treatment technology for developing countries, hence, a way of resolving problem of low quality water for potable uses. PMID:27347529

  11. The Effects of Roof Membrane Color on Moisture Accumulation in Low-slope Commercial Roof Systems

    SciTech Connect

    Kehrer, Manfred

    2011-01-01

    The use of highly reflective roof membrane systems is being promoted and in some cases required in energy codes and green building codes and standards. Highly reflective membranes, which typically are light in color, have demonstrated reduced overall energy consumption in cooling dominated climate. These membranes also are theorized to reduce the heat island effect. Concern has been expressed about using highly reflective roof membrane systems in cool to cold climate zones because they potentially increase moisture accumulation in roof systems. Roof membranes are vapor retarders. The theory is that highly reflective membranes reflect the heat that could enter the roof assembly, potentially providing a condensing surface on the cold side of the roof assembly during winter months. The other concern is that roof systems using highly reflective membranes will not get hot enough during the summer months to dry out moisture that may have condensed or otherwise entered the roof assembly. This study focuses on mechanically attached, highly reflective, single-ply roof systems installed on low-slope (less than 2:12) structures in cool to cold climate zones. Three sources of data are considered when determining the moisture accumulation potential of these systems. 1.Test roof cuts taken during the winter months 2.Modeling data from a building envelope model specifically designed to evaluate moisture accumulation 3.Data from previous studies to determine the effects of roof membrane color on the drying rate of low-slope roof assemblies

  12. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2002-01-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. A new mechanical approach to estimate rock strengths using the acquired drilling parameters has been proposed. This approach takes a number of important factors, that have never been studied in the previous researches, into the considerations. Good results have been shown using the new approach on the testing data.

  13. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2002-04-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. More laboratory tests have been performed in this quarter. The analysis performed on the testing data showed: (1) abnormal rotational accelerations can be used as the indicator of the rock interfaces, and (2) the sharp drops of drilling thrust and torque agree well with the locations of fractures.

  14. Demonstration of energy savings of cool roofs

    SciTech Connect

    Konopacki, S.; Gartland, L.; Akbari, H.; Rainer, L.

    1998-06-01

    Dark roofs raise the summertime air-conditioning demand of buildings. For highly-absorptive roofs, the difference between the surface and ambient air temperatures can be as high as 90 F, while for highly-reflective roofs with similar insulative properties, the difference is only about 20 F. For this reason, cool roofs are effective in reducing cooling energy use. Several experiments on individual residential buildings in California and Florida show that coating roofs white reduces summertime average daily air-conditioning electricity use from 2--63%. This demonstration project was carried out to address some of the practical issues regarding the implementation of reflective roofs in a few commercial buildings. The authors monitored air-conditioning electricity use, roof surface temperature, plenum, indoor, and outdoor air temperatures, and other environmental variables in three buildings in California: two medical office buildings in Gilroy and Davis and a retail store in San Jose. Coating the roofs of these buildings with a reflective coating increased the roof albedo from an average of 0.20--0.60. The roof surface temperature on hot sunny summer afternoons fell from 175 F--120 F after the coating was applied. Summertime average daily air-conditioning electricity use was reduced by 18% (6.3 kWh/1000ft{sup 2}) in the Davis building, 13% (3.6 kWh/1000ft{sup 2}) in the Gilroy building, and 2% (0.4 kWh/1000ft{sup 2}) in the San Jose store. In each building, a kiosk was installed to display information from the project in order to educate and inform the general public about the environmental and energy-saving benefits of cool roofs. They were designed to explain cool-roof coating theory and to display real-time measurements of weather conditions, roof surface temperature, and air-conditioning electricity use. 55 figs., 15 tabs.

  15. Structural performance of light-frame roof assemblies. I, Truss assemblies designed for high variability and wood failure

    Treesearch

    R.W. Wolfe; Monica McCarthy

    1989-01-01

    The first report of a three-part series that covers results of a full-scale roof assemblies research program. The focus of this report is the structural performance of truss assemblies comprising trusses with abnormally high stiffness variability and critical joint strength. Results discussed include properties of truss members and connections. individual truss...

  16. Metal Roofing in a "Class" by Itself.

    ERIC Educational Resources Information Center

    Nimtz, Paul D.

    1990-01-01

    The structural standing seam roof has the advantages of ease of application, low maintenance, and low life-cycle costs. Explains and illustrates how the system's concealed clip attachments are designed so that the roof panels can expand and contract independently of the insulation. (MLF)

  17. Predicting moisture problems in low-slope roofing

    SciTech Connect

    Desjarlais, A.O.; Byars, N.A.

    1998-11-01

    Moisture intrusion is the major reason why low-slope roofing systems fail prematurely. With approximately 75% of all roofing activity being reroofing, the roofing professional is faced with deciding what to do with an existing wet roof on almost a daily basis. This paper describes finite-difference computer modeling that has been performed to address moisture control in low-slope roof systems. Based on a large database of finite difference modeling results, algorithms have been developed that allow the roofing practitioners to simply determine if a roofing system design requires a vapor retarder or if the system can be modified to enhance its tolerance for small leaks. This paper illustrates how modeling results were obtained, describes the process employed to develop the algorithms, and demonstrates how these algorithms can be used to design a moisture tolerant low-slope roof. The range of applicability and limitations of these algorithms is also detailed.

  18. Elicitors aboveground: an alternative for control of a belowground pest

    USDA-ARS?s Scientific Manuscript database

    Plant defense pathways mediate multitrophic interactions above and belowground. Understanding the effects of these pathways on pests and natural enemies above and belowground holds great potential for designing effective control strategies. Here we investigate the effects of aboveground stimulation ...

  19. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof (EFR). 65.44... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Storage Vessels § 65.44 External floating roof (EFR). (a) EFR... emissions by using an external floating roof shall comply with the design requirements listed in...

  20. Raising the Roof.

    ERIC Educational Resources Information Center

    Savage, John

    2000-01-01

    Discusses how the use of metal standing-seam roofs can help conserve energy, and with proper maintenance, be long-lasting. An example is given of one high school's replacement of their leaking roof with a metal standing-seam roof. (GR)

  1. Selecting a Roof Membrane.

    ERIC Educational Resources Information Center

    Waldron, Larry W.

    1990-01-01

    Offers a brief synopsis of the unique characteristics of the following roof membranes: (1) built-up roofing; (2) elastoplastic membranes; (3) modified bitumen membranes; (4) liquid applied membranes; and (5) metal roofing. A chart compares the characteristics of the raw membranes only. (MLF)

  2. EPA's Green Roof Research

    EPA Science Inventory

    This is a presentation on the basics of green roof technology. The presentation highlights some of the recent ORD research projects on green roofs and provices insight for the end user as to the benefits for green roof technology. It provides links to currently available EPA re...

  3. Roof System EPDM Shrinkage.

    ERIC Educational Resources Information Center

    Betker, Edward

    1998-01-01

    Looks at Ethylene Propylene Diene Terpolymer rubber roof membranes and the potential problems associated with this material's shrinkage. Discusses how long such a roof should perform and issues affecting repair or replacement. Recommends that a building's function be considered in any roofing decision. (RJM)

  4. Roof System EPDM Shrinkage.

    ERIC Educational Resources Information Center

    Betker, Edward

    1998-01-01

    Looks at Ethylene Propylene Diene Terpolymer rubber roof membranes and the potential problems associated with this material's shrinkage. Discusses how long such a roof should perform and issues affecting repair or replacement. Recommends that a building's function be considered in any roofing decision. (RJM)

  5. EPA's Green Roof Research

    EPA Science Inventory

    This is a presentation on the basics of green roof technology. The presentation highlights some of the recent ORD research projects on green roofs and provices insight for the end user as to the benefits for green roof technology. It provides links to currently available EPA re...

  6. Economic and environmental evaluation model for selecting the optimum design of green roof systems in elementary schools.

    PubMed

    Kim, JiMin; Hong, TaeHoon; Koo, Choong-Wan

    2012-08-07

    Green-roof systems offer various benefits to man and nature, such as establishing ecological environments, improving landscape and air quality, and offering pleasant living environments. This study aimed to develop an optimal-scenario selection model that considers both the economic and the environmental effect in applying GRSs to educational facilities. The following process was carried out: (i) 15 GRSs scenarios were established by combining three soil and five plant types and (ii) the results of the life cycle CO(2) analyses with the GRSs scenarios were converted to an economic value using certified emission reductions (CERs) carbon credits. Life cycle cost (LCC) analyses were performed based on these results. The results showed that when considering only the currently realized economic value, the conventional roof system is superior to the GRSs. However, the LCC analysis that included the environmental value, revealed that compared to the conventional roof system, the following six GRSs scenarios are superior (cost reduction; reduction ratio; in descending order): scenarios 13 ($195,229; 11.0%), 3 ($188,178; 10.6%), 8 ($181,558; 10.3%), 12 ($130,464; 7.4%), 2 ($124,566; 7.0%), and 7 ($113,931; 6.4%). Although the effect is relatively small in terms of cost reduction, environmental value attributes cannot be ignored in terms of the reduction ratio.

  7. Roof Savings Calculator Suite

    SciTech Connect

    New, Joshua R; Garrett, Aaron; Erdem, Ender; Huang, Yu

    2013-11-22

    The software options currently supported by the simulation engine can be seen/experienced at www.roofcalc.com. It defaults all values to national averages with options to test a base-case (residential or commercial) building versus a comparison building with inputs for building type, location, building vintage, conditioned area, number of floors, and window-to-wall ratio, cooling system efficiency, type of heating, heating system efficiency, duct location, roof/ceiling insulation level, above-sheathing ventilation, radiant barrier, roof thermal mass, roof solar reflectance, roof thermal emittance, utility costs, roof pitch. The Roof Savings Caculator Suite adds utilities and website/web service and the integration of AtticSim with DOE-2.1E, with the end-result being Roof Savings Calculator.

  8. Building Roof Boundary Extraction from LiDAR and Image Data Based on Markov Random Field

    NASA Astrophysics Data System (ADS)

    Dal Poz, A. P.; Fernandes, V. J. M.

    2017-05-01

    In this paper a method for automatic extraction of building roof boundaries is proposed, which combines LiDAR data and highresolution aerial images. The proposed method is based on three steps. In the first step aboveground objects are extracted from LiDAR data. Initially a filtering algorithm is used to process the original LiDAR data for getting ground and non-ground points. Then, a region-growing procedure and the convex hull algorithm are sequentially used to extract polylines that represent aboveground objects from the non-ground point cloud. The second step consists in extracting corresponding LiDAR-derived aboveground objects from a high-resolution aerial image. In order to avoid searching for the interest objects over the whole image, the LiDAR-derived aboveground objects' polylines are photogrammetrically projected onto the image space and rectangular bounding boxes (sub-images) that enclose projected polylines are generated. Each sub-image is processed for extracting the polyline that represents the interest aboveground object within the selected sub-image. Last step consists in identifying polylines that represent building roof boundaries. We use the Markov Random Field (MRF) model for modelling building roof characteristics and spatial configurations. Polylines that represent building roof boundaries are found by optimizing the resulting MRF energy function using the Genetic Algorithm. Experimental results are presented and discussed in this paper.

  9. Advanced Energy Efficient Roof System

    SciTech Connect

    Jane Davidson

    2008-09-30

    options considered to date are not ideal. One approach is to insulate between the trusses at the roof plane. The construction process is time consuming and costs more than conventional attic construction. Moreover, the problems of air infiltration and thermal bridges across the insulation remain. Another approach is to use structurally insulated panels (SIPs), but conventional SIPs are unlikely to be the ultimate solution because an additional underlying support structure is required except for short spans. In addition, wood spline and metal locking joints can result in thermal bridges and gaps in the foam. This study undertook a more innovative approach to roof construction. The goal was to design and evaluate a modular energy efficient panelized roof system with the following attributes: (1) a conditioned and clear attic space for HVAC equipment and additional finished area in the attic; (2) manufactured panels that provide structure, insulation, and accommodate a variety of roofing materials; (3) panels that require support only at the ends; (4) optimal energy performance by minimizing thermal bridging and air infiltration; (5) minimal risk of moisture problems; (6) minimum 50-year life; (7) applicable to a range of house styles, climates and conditions; (8) easy erection in the field; (9) the option to incorporate factory-installed solar systems into the panel; and (10) lowest possible cost. A nationwide market study shows there is a defined market opportunity for such a panelized roof system with production and semi-custom builders in the United States. Senior personnel at top builders expressed interest in the performance attributes and indicate long-term opportunity exists if the system can deliver a clear value proposition. Specifically, builders are interested in (1) reducing construction cycle time (cost) and (2) offering increased energy efficiency to the homebuyer. Additional living space under the roof panels is another low-cost asset identified as part of

  10. Thermal Performance of Vegetative Roofing Systems

    SciTech Connect

    Desjarlais, Andre Omer; Zaltash, Abdolreza; Atchley, Jerald Allen; Ennis, Mike J

    2010-01-01

    Vegetative roofing, otherwise known as green or garden roofing, has seen tremendous growth in the last decade in the United States. The numerous benefits that green roofs provide have helped to fuel their resurgence in industrial and urban settings. There are many environmental and economical benefits that can be realized by incorporating a vegetative roof into the design of a building. These include storm-water retention, energy conservation, reduction in the urban heat island effect, increased longevity of the roofing membrane, the ability of plants to create biodiversity and filter air contaminants, and beautification of the surroundings by incorporating green space. The vegetative roof research project at Oak Ridge National Laboratory (ORNL) was initiated to quantify the thermal performance of various vegetative roofing systems relative to black and white roofs. Single Ply Roofing Institute (SPRI) continued its long-term commitment to cooperative research with ORNL in this project. Low-slope roof systems for this study were constructed and instrumented for continuous monitoring in the mixed climate of East Tennessee. This report summarizes the results of the annual cooling and heating loads per unit area of three vegetative roofing systems with side-by-side comparison to black and white roofing systems as well as a test section with just the growing media without plants. Results showed vegetative roofs reduced heat gain (reduced cooling loads) compared to the white control system due to the thermal mass, extra insulation, and evapo-transpiration associated with the vegetative roofing systems. The 4-inch and tray systems reduced the heat gain by approximately 61%, while the reduction with the 8-inch vegetative roof was found to be approximately 67%. The vegetative roofing systems were more effective in reducing heat gain than in reducing heat losses (heating loads). The reduction in heat losses for the 4-inch and tray systems were found to be approximately 40

  11. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... internal floating roof (IFR). (a) IFR design requirements. The owner or operator who elects to control... installing the control equipment required to comply with § 65.42(b)(1) or (3), visually inspect the internal... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Fixed roof with an internal...

  12. IMPROVED ROOF STABILIZATION TECHNOLOGIES

    SciTech Connect

    M.A. Ebadian, Ph.D.

    1999-01-01

    Many U.S. Department of Energy (DOE) remediation sites have performed roof repair and roof replacement to stabilize facilities prior to performing deactivation and decommissioning (D&D) activities. This project will review the decision criteria used by these DOE sites, along with the type of repair system used for each different roof type. Based on this information, along with that compiled from roofing experts, a decision-making tool will be generated to aid in selecting the proper roof repair systems. Where appropriate, innovative technologies will be reviewed and applied to the decision-making tool to determine their applicability. Based on the results, applied research and development will be conducted to develop a method to repair these existing roofing systems, while providing protection for the D and D worker in a cost-efficient manner.

  13. Mine roof support

    SciTech Connect

    Bollmann, A.

    1981-02-24

    A mine roof support has a base and a roof shield pivoted to the base and carrying at its upper end a pivoted cap which is urged upwardly against the mine roof by a hydraulic pit prop reacting between the cap and the base. The lower end of the roof shield is connected to the base by two links each having a pivot cooperating with a pivot on the roof shield, and a pivot cooperating with a pivot on the base. In addition, the base and/or the lower end of the roof shield has an auxiliary for each link and each link has an auxiliary pivot which can be connected with one of the auxiliary pivots of the base or lower end.

  14. Eliciting maize defense pathways aboveground attracts belowground biocontrol agents

    PubMed Central

    Filgueiras, Camila Cramer; Willett, Denis S.; Pereira, Ramom Vasconcelos; Moino Junior, Alcides; Pareja, Martin; Duncan, Larry W.

    2016-01-01

    Plant defense pathways mediate multitrophic interactions above and belowground. Understanding the effects of these pathways on pests and natural enemies above and belowground holds great potential for designing effective control strategies. Here we investigate the effects of aboveground stimulation of plant defense pathways on the interactions between corn, the aboveground herbivore adult Diabrotica speciosa, the belowground herbivore larval D. speciosa, and the subterranean ento-mopathogenic nematode natural enemy Heterorhabditis amazonensis. We show that adult D. speciosa recruit to aboveground herbivory and methyl salicylate treatment, that larval D. speciosa are relatively indiscriminate, and that H. amazonensis en-tomopathogenic nematodes recruit to corn fed upon by adult D. speciosa. These results suggest that entomopathogenicnematodes belowground can be highly attuned to changes in the aboveground parts of plants and that biological control can be enhanced with induced plant defense in this and similar systems. PMID:27811992

  15. Decision Guide for Roof Slope Selection

    SciTech Connect

    Sharp, T.R.

    1988-01-01

    This decision guide has been written for personnel who are responsible for the design, construction, and replacement of Air Force roofs. It provides the necessary information and analytical tools for making prudent and cost-effective decisions regarding the amount of slope to provide in various roofing situations. Because the expertise and experience of the decision makers will vary, the guide contains both basic slope-related concepts as well as more sophisticated technical data. This breadth of information enables the less experienced user to develop an understanding of roof slope issues before applying the more sophisticated analytical tools, while the experienced user can proceed directly to the technical sections. Although much of this guide is devoted to the analysis of costs, it is not a cost-estimating document. It does, however, provide the reader with the relative costs of a variety of roof slope options; and it shows how to determine the relative cost-effectiveness of different options. The selection of the proper roof slope coupled with good roof design, a quality installation, periodic inspection, and appropriate maintenance and repair will achieve the Air Force's objective of obtaining the best possible roofing value for its buildings.

  16. Evolution of cool-roof standards in the United States

    SciTech Connect

    Akbari, Hashem; Akbari, Hashem; Levinson, Ronnen

    2008-07-11

    Roofs that have high solar reflectance and high thermal emittance stay cool in the sun. A roof with lower thermal emittance but exceptionally high solar reflectance can also stay cool in the sun. Substituting a cool roof for a noncool roof decreases cooling-electricity use, cooling-power demand, and cooling-equipment capacity requirements, while slightly increasing heating-energy consumption. Cool roofs can also lower citywide ambient air temperature in summer, slowing ozone formation and increasing human comfort. Provisions for cool roofs in energy-efficiency standards can promote the building- and climate-appropriate use of cool roofing technologies. Cool-roof requirements are designed to reduce building energy use, while energy-neutral cool-roof credits permit the use of less energy-efficient components (e.g., larger windows) in a building that has energy-saving cool roofs. Both types of measures can reduce the life-cycle cost of a building (initial cost plus lifetime energy cost). Since 1999, several widely used building energy-efficiency standards, including ASHRAE 90.1, ASHRAE 90.2, the International Energy Conservation Code, and California's Title 24 have adopted cool-roof credits or requirements. This paper reviews the technical development of cool-roof provisions in the ASHRAE 90.1, ASHRAE 90.2, and California Title 24 standards, and discusses the treatment of cool roofs in other standards and energy-efficiency programs. The techniques used to develop the ASHRAE and Title 24 cool-roof provisions can be used as models to address cool roofs in building energy-efficiency standards worldwide.

  17. Roofing Source File.

    ERIC Educational Resources Information Center

    American School & University, 1998

    1998-01-01

    Provides guidelines for school administrators to aid in the selection of school-roofing systems, and information required to make specification and purchasing decisions. Low-slope roofing systems are examined, as are multiply systems such as modified bitumen, EPDM, thermoplastic, metal, and foam. (GR)

  18. Roofing Source File.

    ERIC Educational Resources Information Center

    American School & University, 1998

    1998-01-01

    Provides guidelines for school administrators to aid in the selection of school-roofing systems, and information required to make specification and purchasing decisions. Low-slope roofing systems are examined, as are multiply systems such as modified bitumen, EPDM, thermoplastic, metal, and foam. (GR)

  19. Guide to Cool Roofs

    SciTech Connect

    2011-02-01

    Traditional dark-colored roofing materials absorb sunlight, making them warm in the sun and increasing the need for air conditioning. White or special "cool color" roofs absorb less sunlight, stay cooler in the sun and transmit less heat into the building.

  20. Why Cool Roofs?

    SciTech Connect

    Chu, Steven

    2010-01-01

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  1. Million Solar Roofs

    SciTech Connect

    2003-11-01

    Since its announcement in June 1997, the Million Solar Roofs Initiative has generated a major buzz in communities, states, and throughout the nation. With more than 300,000 installations, the buzz is getting louder. This brochure describes Million Solar Roofs activities and partnerships.

  2. Why Cool Roofs?

    ScienceCinema

    Chu, Steven

    2016-07-12

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  3. Protected Membrane Roofs: A Sustainable Roofing Solution.

    ERIC Educational Resources Information Center

    Roodvoets, David L.

    2003-01-01

    Examines the benefits of protected membrane roofing (PMR) for school buildings. PMR uses an upside-down approach, where the insulation is placed on top of the waterproofing membrane to improve membrane effectiveness, reduce ultraviolet degradation, and improve insulation efficiency. The article explains what makes PMR sustainable, focusing on…

  4. Protected Membrane Roofs: A Sustainable Roofing Solution.

    ERIC Educational Resources Information Center

    Roodvoets, David L.

    2003-01-01

    Examines the benefits of protected membrane roofing (PMR) for school buildings. PMR uses an upside-down approach, where the insulation is placed on top of the waterproofing membrane to improve membrane effectiveness, reduce ultraviolet degradation, and improve insulation efficiency. The article explains what makes PMR sustainable, focusing on…

  5. Aboveground biomass in Tibetan grasslands

    Treesearch

    Y.H. Yang; J.Y. Fang; Y.D. Pan; C.J. Ji

    2009-01-01

    This study investigated spatial patterns and environmental controls of aboveground biomass (AGB) in alpine grasslands on the Tibetan Plateau by integrating AGB data collected from 135 sites during 2001-2004 and concurrent enhanced vegetation index derived from MODIS data sets. The AGB was estimated at 68.8 gm-2, with a larger value (90.8 gm

  6. Improved roof stabilization technologies

    SciTech Connect

    Ebadian, M.A.

    1998-01-01

    Decontamination and decommissioning (D and D) activities require that personnel have access to all areas of structures, some of which are more than 40 years old. In many cases, these structures have remained in a standby condition for up to 10 years; few preventative maintenance activities have been performed on them because of lack of funding or a defined future plan of action. This situation has led to deteriorated building conditions, resulting in potential personnel safety hazards. In addition, leaky roofs allow water to enter the buildings, which can cause the spread of contamination and increase building deterioration, worsening the already unsafe working conditions. To ensure worker safety and facilitate building dismantlement, the assessment of roof stabilization techniques applicable to US Department of Energy (DOE) structures has become an important issue. During Fiscal year 1997 (FY97), a comprehensive reliability-based model for the structural stabilization analysis of roof system in complex structures was developed. The model consists of three major components: a material testing method, a deterministic structural computer model, and a reliability-based optimization, and probabilistic analyses of roof structures can be implemented. Given site-specific needs, this model recommends the most appropriate roof stabilization system. This model will give not only an accurate evaluation of the existing roof system in complex structures, but it will also be a reliable method to aid the decision-making process. This final report includes in its appendix a Users` Manual for the Program of Deterministic and Reliability Analysis of Roof Structures.

  7. Green Roofs for Stormwater Management

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Results indicate that the green roofs are capable of removing 40% of the annual rainfall volume from a roof through retention and evapotranspiration. Rainfall not retained by green roofs is detained, effectively...

  8. Green Roofs for Stormwater Management

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Results indicate that the green roofs are capable of removing 40% of the annual rainfall volume from a roof through retention and evapotranspiration. Rainfall not retained by green roofs is detained, effectively...

  9. Solar power roof shingle

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G.

    1975-01-01

    Silicon solar cell module provides both all-weather protection and electrical power. Module consists of array of circular silicon solar cells bonded to fiberglass substrate roof shingle with fluorinated ethylene propylene encapsulant.

  10. Green Roofs: Federal Energy Management Program (FEMP) Federal Technology Alert

    SciTech Connect

    Scholz-Barth, K.; Tanner, S.

    2004-09-01

    In a ''green roof,'' a layer of vegetation (e.g., a roof garden) covers the surface of a roof to provide shade, cooler indoor and outdoor temperatures, and effective storm-water management to reduce runoff. The main components are waterproofing, soil, and plants. There are two basic kinds: intensive and extensive. An intensive green roof often features large shrubs and trees, and it can be expensive to install and maintain. An extensive green roof features shallow soil and low-growing, horizontally spreading plants that can thrive in the alpine conditions of many rooftops. These plants do not require a lot of water or soil, and they can tolerate a significant amount of exposure to the sun and wind. This Federal Technology Alert focuses on the benefits, design, and implementation of extensive green roofs and includes criteria for their use on federal facilities.

  11. Aboveground storage tank double bottom cathodic protection

    SciTech Connect

    Surkein, M.B.

    1995-12-31

    Cathodic protection is typically used to achieve corrosion control between bottoms of aboveground storage tanks with double bottoms. To determine the proper design of such systems, an investigation was conducted on the performance of two different cathodic protection system designs utilizing zinc ribbon anodes. A full scale field test on a 35 meter (115 feet) diameter tank was conducted to determine cathodic protection system performance. The test included periodic measurement of tank bottom steel potentials including on, instant off and polarization decay, anode current output and tank product level measurements.Results showed that zinc ribbon anode spacing in a chord fashion of 1.2 meter (4 feet) or less can be effective to achieve cathodic protection according to industry accepted standards. Utilizing the design information gained by the study, a standard sacrificial anode and impressed current anode cathodic protection system has been developed.

  12. ROOF, A view looking north from the stair tower roof ...

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

    ROOF, A view looking north from the stair tower roof at the external piping - Department of Energy, Mound Facility, Hydrolysis House Building (HH Building), One Mound Road, Miamisburg, Montgomery County, OH

  13. 8. Detail of interior roof showing truss bracing and roof ...

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

    8. Detail of interior roof showing truss bracing and roof plank decking; view to east from approximately the center of the shelter. - Warm River Shelter, Warm River Campground, Ashton, Fremont County, ID

  14. 5. MAIN BAY SHOWING ROOF CONSTRUCTION, ROOF TRUSS, CLERESTORY MONITOR, ...

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

    5. MAIN BAY SHOWING ROOF CONSTRUCTION, ROOF TRUSS, CLERESTORY MONITOR, AND GIRDER FOR ELECTRIC OVERHEAD TRAVEL CRANE (BOTTOM) - Oldman Boiler Works, Boilershop, 32 Illinois Street, Buffalo, Erie County, NY

  15. Rod shop, roof and truss detail showing older pink roof ...

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

    Rod shop, roof and truss detail showing older pink roof truss, newer pratt truss, and longitudinal, truss for overhead traveling crane - Chicago, Burlington & Quincy Railroad, Roundhouse & Shops, Broadway & Spring Streets, Aurora, Kane County, IL

  16. Green Roofs for Stormwater Runoff Control - Abstract

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  17. Green Roofs for Stormwater Runoff Control - Abstract

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  18. 24. Roof detail from liftbed truck, showing pan roof above ...

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

    24. Roof detail from lift-bed truck, showing pan roof above breezeway, with sawn redwood trim, tube-type drains; note missing rain gutter at roof edge, deteriorated condition of slates; view to south, 90mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  19. How To Prevent Roof Abuse.

    ERIC Educational Resources Information Center

    Hutchinson, Thomas W.

    2000-01-01

    Discusses ways to prevent school roofing failure through good maintenance practice and the proper handling of emergency situations. What types of problems show up when roofs are not maintained are highlighted. (GR)

  20. Photovoltaic roofing tile systems

    NASA Astrophysics Data System (ADS)

    Melchior, B.

    The integration of photovoltaic (PV) systems in architecture is discussed. A PV-solar roofing tile system with polymer concrete base; PV-roofing tile with elastomer frame profiles and aluminum profile frames; contact technique; and solar cell modules measuring technique are described. Field tests at several places were conducted on the solar generator, electric current behavior, battery station, electric installation, power conditioner, solar measuring system with magnetic bubble memory technique, data transmission via telephone modems, and data processing system. The very favorable response to the PV-compact system proves the commercial possibilities of photovoltaic integration in architecture.

  1. ENERGY STAR Certified Roof Products

    EPA Pesticide Factsheets

    Certified models meet all ENERGY STAR requirements as listed in the Version 2.3 ENERGY STAR Program Requirements for Roof Products that are effective as of July 1, 2012 or the Version 3.0 ENERGY STAR Program Requirements for Roof Products that are effective as of July 1, 2017 . A detailed listing of key efficiency criteria are available at http://www.energystar.gov/index.cfm?c=roof_prods.pr_crit_roof_products

  2. Integrated roof wind energy system

    NASA Astrophysics Data System (ADS)

    Suma, A. B.; Ferraro, R. M.; Dano, B.; Moonen, S. P. G.

    2012-10-01

    Wind is an attractive renewable source of energy. Recent innovations in research and design have reduced to a few alternatives with limited impact on residential construction. Cost effective solutions have been found at larger scale, but storage and delivery of energy to the actual location it is used, remain a critical issue. The Integrated Roof Wind Energy System is designed to overcome the current issues of urban and larger scale renewable energy system. The system is built up by an axial array of skewed shaped funnels that make use of the Venturi Effect to accelerate the wind flow. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a vertical-axis wind turbine in the top of the roof for generation of a relatively high amount of energy. The methods used in this overview of studies include an array of tools from analytical modelling, PIV wind tunnel testing, and CFD simulation studies. The results define the main design parameters for an efficient system, and show the potential for the generation of high amounts of renewable energy with a novel and effective system suited for the built environment.

  3. High-Tech Roof Management.

    ERIC Educational Resources Information Center

    Benzie, Tim

    1997-01-01

    Describes the use of a computerized roof management system (CRMS) for school districts to foster multiple roof maintenance efficiency and cost effectiveness. Highlights CRMS software manufacturer choices, as well as the types of nondestructive testing equipment tools that can be used to evaluate roof conditions. (GR)

  4. High-Tech Roof Management.

    ERIC Educational Resources Information Center

    Benzie, Tim

    1997-01-01

    Describes the use of a computerized roof management system (CRMS) for school districts to foster multiple roof maintenance efficiency and cost effectiveness. Highlights CRMS software manufacturer choices, as well as the types of nondestructive testing equipment tools that can be used to evaluate roof conditions. (GR)

  5. ABOVEGROUND NITROGEN USE EFFICIENCY AND ...

    EPA Pesticide Factsheets

    Long-term nitrogen (N) fertilization studies suggest shifting dominance from Spartina alterniflora to Distichlis spicata, although the underlying mechanism is unclear. A limitation on our ability to predict changes is a poor understanding of resource use under ambient conditions. The present project compares growth rates and N use dynamics between two emerging salt marsh dominants, S. alterniflora and D. spicata. We hypothesize that under ambient Narragansett Bay nutrient conditions, S. alterniflora is a more efficient user of N than D. spicata. Spartina alterniflora and D. spicata cores were collected from the field and raised in a greenhouse. Heights of all stems were measured weekly to determine growth rates. To understand N movement, a pulse of 15N was added and three cores were sacrificed each subsequent week. Live aboveground biomass was separated into stems and leaves, with leaves categorized based on their position from the top of the stem. Samples were analyzed by isotope ratio mass spectrometry to trace N accumulation in different pools over time. One week after the 15N pulse, most of the aboveground 15N was bound in the stems and the youngest leaves. Efficient nutrient transfer in photosynthetic material likely provides a stronger competitive advantage for taller plants, which are able to compete better for light. Growth rates of S. alterniflora proved to be more variable over time than that of D. spicata. A better understanding of N dynamics under am

  6. ABOVEGROUND NITROGEN USE EFFICIENCY AND ...

    EPA Pesticide Factsheets

    Long-term nitrogen (N) fertilization studies suggest shifting dominance from Spartina alterniflora to Distichlis spicata, although the underlying mechanism is unclear. A limitation on our ability to predict changes is a poor understanding of resource use under ambient conditions. The present project compares growth rates and N use dynamics between two emerging salt marsh dominants, S. alterniflora and D. spicata. We hypothesize that under ambient Narragansett Bay nutrient conditions, S. alterniflora is a more efficient user of N than D. spicata. Spartina alterniflora and D. spicata cores were collected from the field and raised in a greenhouse. Heights of all stems were measured weekly to determine growth rates. To understand N movement, a pulse of 15N was added and three cores were sacrificed each subsequent week. Live aboveground biomass was separated into stems and leaves, with leaves categorized based on their position from the top of the stem. Samples were analyzed by isotope ratio mass spectrometry to trace N accumulation in different pools over time. One week after the 15N pulse, most of the aboveground 15N was bound in the stems and the youngest leaves. Efficient nutrient transfer in photosynthetic material likely provides a stronger competitive advantage for taller plants, which are able to compete better for light. Growth rates of S. alterniflora proved to be more variable over time than that of D. spicata. A better understanding of N dynamics under am

  7. Nondestructive inspection requirements aboveground storage tanks (ASTs)

    SciTech Connect

    Sherlock, C.N.

    1995-12-31

    Aboveground storage tanks (ASTs) are designed, built and nondestructively inspected to a variety of Standards and Codes. This discussion deals only with the nondestructive inspection requirements for the more common Standards and Codes generated in the United States for these type structures. The problems of how to communicate to the NDT technician the required inspection or testing information within these Standard or Code documents for both new ASTs and repaired, reconstructed or altered ASTs are discussed. In the presentation of this paper, NDT applications, acceptance criteria and personnel requirements for welds or components for radiography, ultrasonic alternatives to radiography, magnetic particle, liquid penetrant, visual and leak testing for the mentioned Standards and Codes will be reviewed.

  8. Nondestructive inspection requirements for aboveground storage tanks

    SciTech Connect

    Sherlock, C.N.

    1996-02-01

    Aboveground storage tanks (ASTs) are designed, built, and nondestructively inspected to a variety of codes and standards. This discussion deals only with the nondestructive inspection requirements for the more common codes and standards generated in the US for these type structures. Standards and codes for which nondestructive inspection or nondestructive testing (NDT) requirements will be reviewed are listed. This article reviews the NDT applications, acceptance criteria, and personnel requirements for welds or components for radiography, ultrasonic alternatives to radiography, magnetic particle, liquid penetrant, visual, and leak testing for the above standards and codes. The problems of how to communicate to the NDT technician the required inspection or testing information within these standard or code documents for both new ASTs and repaired, reconstructed, or altered ASTs are discussed.

  9. Mine roof drill bits that save money

    SciTech Connect

    Ford, L.M.

    1982-04-01

    Sandia National Laboratories, Albuquerque, NM, has developed advanced technology roof bolt drill bits which have demonstrated longer life, higher penetration rates at lower thrust and torque, and lower specific energy than conventional roof bolt drill bits. This is achieved through use of advanced technology cutting materials and novel bit body designs. These bits have received extensive laboratory and mine testing. Their performance has been evaluated and estimates of their value in reducing coal production costs have been made. The work was sponsored by the United States Department of Energy.

  10. Structural assessment of roof decking using visual inspection methods

    SciTech Connect

    Giller, R.A.; McCoy, R.M.; Wagenblast, G.R.

    1993-10-01

    The Hanford Site has approximately 1,100 buildings, some of which date back to the early 1940s. The roof on these buildings provides a weather resisting cover as well as the load resisting structure. Past experience has been that these roof structures may have structural modifications, the weather resisting membrane may have been replaced several times, and the members may experience some type of material degradation. This material degradation has progressed to cause the collapse of some roof deck members. The intent of the Hanford Site Central Engineering roof assessment effort is to provide an expedient structural assessment of the large number of buildings at the Hanford Site. This assessment is made by qualified structural inspectors following the {open_quotes}Preliminary Assessment{close_quote} procedures given in the American Society of Civil Engineers (ASCE) Standard ASCE 11-90. This roof assessment effort does not provide a total qualification of the roof for the design or in-place loads. This inspection does provide a reasonable estimate of the roof loading capacity to determine if personnel access restrictions are needed. A document search and a visual walkdown inspection provide the initial screening to identify modifications and components having questionable structural integrity. The structural assessment consists of baseline dead and live load stress calculations of all roofing components based on original design material strengths. The results of these assessments are documented in a final report which is retrievable form that future inspections will have comparative information.

  11. Green roof hydrologic performance and modeling: a review.

    PubMed

    Li, Yanling; Babcock, Roger W

    2014-01-01

    Green roofs reduce runoff from impervious surfaces in urban development. This paper reviews the technical literature on green roof hydrology. Laboratory experiments and field measurements have shown that green roofs can reduce stormwater runoff volume by 30 to 86%, reduce peak flow rate by 22 to 93% and delay the peak flow by 0 to 30 min and thereby decrease pollution, flooding and erosion during precipitation events. However, the effectiveness can vary substantially due to design characteristics making performance predictions difficult. Evaluation of the most recently published study findings indicates that the major factors affecting green roof hydrology are precipitation volume, precipitation dynamics, antecedent conditions, growth medium, plant species, and roof slope. This paper also evaluates the computer models commonly used to simulate hydrologic processes for green roofs, including stormwater management model, soil water atmosphere and plant, SWMS-2D, HYDRUS, and other models that are shown to be effective for predicting precipitation response and economic benefits. The review findings indicate that green roofs are effective for reduction of runoff volume and peak flow, and delay of peak flow, however, no tool or model is available to predict expected performance for any given anticipated system based on design parameters that directly affect green roof hydrology.

  12. 7 CFR 3201.11 - Roof coatings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., overlap with the following EPA-designated recovered content product: Roofing Materials. USDA is requesting that manufacturers of these qualifying biobased products provide information for the BioPreferred Web... not the product contains any type of recovered material, in addition to biobased ingredients,...

  13. 7 CFR 3201.11 - Roof coatings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., overlap with the following EPA-designated recovered content product: Roofing Materials. USDA is requesting that manufacturers of these qualifying biobased products provide information for the BioPreferred Web... not the product contains any type of recovered material, in addition to biobased ingredients,...

  14. 7 CFR 3201.11 - Roof coatings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., overlap with the following EPA-designated recovered content product: Roofing Materials. USDA is requesting that manufacturers of these qualifying biobased products provide information for the BioPreferred Web... not the product contains any type of recovered material, in addition to biobased ingredients,...

  15. Design and performance of B4WarmED, an aboveground and belowground free-air warming experiment at the temperate-boreal forest ecotone

    USDA-ARS?s Scientific Manuscript database

    Conducting manipulative climate change experiments in forests is challenging, given their spatial heterogeneity and canopy complexity. One specific challenge involves warming both plants and soils to depth in ecosystems without much bare ground. We describe the design, implementation, and performanc...

  16. Automated Aboveground Carbon Estimation of Forests with Remote Sensing

    NASA Astrophysics Data System (ADS)

    Gordon, Piper

    Canada's forests are believed to contain 86 gigatons of carbon, stored above and below ground. These forests are large in area, making them difficult to monitor using conventional means. Understanding the carbon cycle and the role of forests as carbon sinks is crucial in the investigation and mitigation of climate change to address national obligations. One economical solution for monitoring the carbon content of Canada's forests is the development of an automated computer system which uses multisource remotely sensed data to estimate the aboveground carbon of trees. The process involves data fusion of remotely sensed hyperspectral data for tree species information and lidar (light detection and ranging) and radar (radio detection and ranging) for tree height. The size and dimensionality of the data necessitate the efficient use of computing resources for analysis. The outcome is a useful carbon measuring system. The three research questions are: (1) How do we map with remote sensing aboveground carbon in the forests? (2) How do we determine the accuracies of these aboveground carbon maps? (3) How can an automated system be designed for creating aboveground carbon maps?

  17. Green roof systems: a study of public attitudes and preferences in southern Spain.

    PubMed

    Fernandez-Cañero, Rafael; Emilsson, Tobias; Fernandez-Barba, Carolina; Herrera Machuca, Miguel Ángel

    2013-10-15

    This study investigates people's preconceptions of green roofs and their visual preference for different green roof design alternatives in relation to behavioral, social and demographical variables. The investigation was performed as a visual preference study using digital images created to represent eight different alternatives: gravel roof, extensive green roof with Sedums not in flower, extensive green roof with sedums in bloom, semi-intensive green roof with sedums and ornamental grasses, semi-intensive green roof with shrubs, intensive green roof planted with a lawn, intensive green roof with succulent and trees and intensive green roof with shrubs and trees. Using a Likert-type scale, 450 respondents were asked to indicate their preference for each digital image. Results indicated that respondents' sociodemographic characteristics and childhood environmental background influenced their preferences toward different green roof types. Results also showed that green roofs with a more careful design, greater variety of vegetation structure, and more variety of colors were preferred over alternatives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Construction of Experimental Roofing.

    DTIC Science & Technology

    1981-11-01

    64 m) of rigid closed-cell inorganic board in hot asphalt. 4. Bonding a 60-mil- (1.5-ram)- thick EPDM membrane to the insulation surface. - 15 a...specified that the existing roofing, flashing, lightweight concrete fill, rigid board insulation, and earthquake copper bel- lows be removed down to...asphalt-saturated and coated inorganic base sheet in hot asphalt. 3. Providing lightweight asphaltic concrete insulating fill and two courses of rigid

  19. Steel Roofing Systems Have School Districts Looking Up.

    ERIC Educational Resources Information Center

    Werner, Michael F.

    2001-01-01

    Examines the leading benefits of choosing steel roofing for educational facilities. Benefits examined are durability, energy efficiency, aesthetics and design flexibility, and construction efficiency and low life cycle cost. (GR)

  20. 16. INTERIOR OF TAN 629 HANGAR, TAKEN FROM HIGH ROOF ...

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

    16. INTERIOR OF TAN 629 HANGAR, TAKEN FROM HIGH ROOF ON NORTH SIDE, FACING SOUTH. DETAIL OF EMPENNAGE DOOR DESIGNED FOR ENTRY OF AIRCRAFT TAIL ASSEMBLY. - Idaho National Engineering Laboratory, Test Area North, Hangar No. 629, Scoville, Butte County, ID

  1. Steel Roofing Systems Have School Districts Looking Up.

    ERIC Educational Resources Information Center

    Werner, Michael F.

    2001-01-01

    Examines the leading benefits of choosing steel roofing for educational facilities. Benefits examined are durability, energy efficiency, aesthetics and design flexibility, and construction efficiency and low life cycle cost. (GR)

  2. Producing superhydrophobic roof tiles.

    PubMed

    Carrascosa, Luis A M; Facio, Dario S; Mosquera, Maria J

    2016-03-04

    Superhydrophobic materials can find promising applications in the field of building. However, their application has been very limited because the synthesis routes involve tedious processes, preventing large-scale application. A second drawback is related to their short-term life under outdoor conditions. A simple and low-cost synthesis route for producing superhydrophobic surfaces on building materials is developed and their effectiveness and their durability on clay roof tiles are evaluated. Specifically, an organic-inorganic hybrid gel containing silica nanoparticles is produced. The nanoparticles create a densely packed coating on the roof tile surface in which air is trapped. This roughness produces a Cassie-Baxter regime, promoting superhydrophobicity. A surfactant, n-octylamine, was also added to the starting sol to catalyze the sol-gel process and to coarsen the pore structure of the gel network, preventing cracking. The application of ultrasound obviates the need to use volatile organic compounds in the synthesis, thereby making a 'green' product. It was also demonstrated that a co-condensation process effective between the organic and inorganic species is crucial to obtain durable and effective coatings. After an aging test, high hydrophobicity was maintained and water absorption was completely prevented for the roof tile samples under study. However, a transition from a Cassie-Baxter to a Wenzel state regime was observed as a consequence of the increase in the distance between the roughness pitches produced by the aging of the coating.

  3. Producing superhydrophobic roof tiles

    NASA Astrophysics Data System (ADS)

    Carrascosa, Luis A. M.; Facio, Dario S.; Mosquera, Maria J.

    2016-03-01

    Superhydrophobic materials can find promising applications in the field of building. However, their application has been very limited because the synthesis routes involve tedious processes, preventing large-scale application. A second drawback is related to their short-term life under outdoor conditions. A simple and low-cost synthesis route for producing superhydrophobic surfaces on building materials is developed and their effectiveness and their durability on clay roof tiles are evaluated. Specifically, an organic-inorganic hybrid gel containing silica nanoparticles is produced. The nanoparticles create a densely packed coating on the roof tile surface in which air is trapped. This roughness produces a Cassie-Baxter regime, promoting superhydrophobicity. A surfactant, n-octylamine, was also added to the starting sol to catalyze the sol-gel process and to coarsen the pore structure of the gel network, preventing cracking. The application of ultrasound obviates the need to use volatile organic compounds in the synthesis, thereby making a ‘green’ product. It was also demonstrated that a co-condensation process effective between the organic and inorganic species is crucial to obtain durable and effective coatings. After an aging test, high hydrophobicity was maintained and water absorption was completely prevented for the roof tile samples under study. However, a transition from a Cassie-Baxter to a Wenzel state regime was observed as a consequence of the increase in the distance between the roughness pitches produced by the aging of the coating.

  4. The Benefits of Preventive Roof Maintenance.

    ERIC Educational Resources Information Center

    Kalinger, Peter

    1998-01-01

    Explains how to convince school administration of the importance of roof-maintenance programs as a way of extending roof life and saving money, even in the presence of roof warranties. Discusses techniques for evaluating the cost benefits of roof maintenance and the importance of creating a roof historical file. (GR)

  5. The “shape” and “meaning” of the roof arts in Chinese classical architecture

    NASA Astrophysics Data System (ADS)

    Li, Xianda; liu, Yu

    2017-04-01

    This paper takes the “roof” in Chinese classical architecture as the research object. The breakthrough point of this paper would be the perspective of design aesthetics. Through the rational and perceptual analysis of the roof art, this paper would reveal that the roof shape has the double artistic features: “beauty of shape” and “beauty of idea”. This paper would have a comprehensive analysis for the following aspects: the rational method of roof construction, the emotional feeling of the roof construction and the implied meaning of beauty in the roof construction.

  6. Ecological linkages between aboveground and belowground biota.

    PubMed

    Wardle, David A; Bardgett, Richard D; Klironomos, John N; Setälä, Heikki; van der Putten, Wim H; Wall, Diana H

    2004-06-11

    All terrestrial ecosystems consist of aboveground and belowground components that interact to influence community- and ecosystem-level processes and properties. Here we show how these components are closely interlinked at the community level, reinforced by a greater degree of specificity between plants and soil organisms than has been previously supposed. As such, aboveground and belowground communities can be powerful mutual drivers, with both positive and negative feedbacks. A combined aboveground-belowground approach to community and ecosystem ecology is enhancing our understanding of the regulation and functional significance of biodiversity and of the environmental impacts of human-induced global change phenomena.

  7. Stormwater Attenuation by Green Roofs

    NASA Astrophysics Data System (ADS)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  8. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  9. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  10. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  11. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  12. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment:...

  13. Accidents due to falls from roof slabs.

    PubMed

    Rudelli, Bruno Alves; Silva, Marcelo Valerio Alabarce da; Akkari, Miguel; Santili, Claudio

    2013-01-01

    CONTEXT AND OBJECTIVE Falls from the roof slabs of houses are accidents of high potential severity that occur in large Brazilian cities and often affect children and adolescents. The aims of this study were to characterize the factors that predispose towards this type of fall involving children and adolescents, quantify the severity of associated lesions and suggest preventive measures. DESIGN AND SETTING Descriptive observational prospective longitudinal study in two hospitals in the metropolitan region of São Paulo. METHODS Data were collected from 29 cases of falls from roof slabs involving children and adolescents between October 2008 and October 2009. RESULTS Cases involving males were more prevalent, accounting for 84%. The predominant age group was schoolchildren (7 to 12 years old; 44%). Leisure activities were most frequently being practiced on the roof slab at the time of the fall (86%), and flying a kite was the most prevalent game (37.9%). In 72% of the cases, the children were unaccompanied by an adult responsible for them. Severe conditions such as multiple trauma and traumatic brain injuries resulted from 79% of the accidents. CONCLUSION Falls from roof slabs are accidents of high potential severity, and preventive measures aimed towards informing parents and guardians about the dangers and risk factors associated with this type of accident are needed, along with physical protective measures, such as low walls around the slab and gates with locks to restrict free access to these places.

  14. Development of a Roof Savings Calculator

    SciTech Connect

    New, Joshua Ryan; Miller, William A; Desjarlais, Andre Omer; Erdem, Ender; Huang, Joe

    2011-01-01

    A web-based Roof Savings Calculator (RSC) has been deployed for the Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. This tool employs the latest web technologies and usability design to provide an easy input interface to an annual simulation of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim. Building defaults were assigned and can provide estimated annual energy and cost savings after the user selects nothing more than building location. In addition to cool reflective roofs, the RSC tool can simulate multiple roof types at arbitrary inclinations. There are options for above sheathing ventilation, radiant barriers, and low-emittance surfaces. The tool also accommodates HVAC ducts either in the conditioned space or in the attic with custom air leakage rates. Multiple layers of building materials, ceiling and deck insulation, and other parameters can be compared side-by-side to generate an energy/cost savings estimate between two buildings. The RSC tool was benchmarked against field data for demonstration homes in Ft. Irwin, CA.

  15. Development of a Roof Savings Calculator

    SciTech Connect

    New, Joshua Ryan; Miller, William A; Huang, Joe; Erdem, Ender

    2011-01-01

    A web-based Roof Savings Calculator (RSC) has been deployed for the Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. This tool employs the latest web technologies and usability design to provide an easy input interface to an annual simulation of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim. Building defaults were assigned and can provide annual energy and cost savings after the user selects nothing more than building location. In addition to cool reflective roofs, the RSC tool can simulate multiple roof types at arbitrary inclinations. There are options for above sheathing ventilation, radiant barriers and low-emittance surfaces. The tool also accommodates HVAC ducts either in the conditioned space or in the attic with custom air leakage rates. Multiple layers of thermal mass, ceiling insulation and other parameters can be compared side-by-side to generate energy/cost savings between two buildings. The RSC tool was benchmarked against field data for demonstration homes in Ft Irwin, CA.

  16. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2002-07-15

    Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. Field tests have been performed in two underground coal mines in this quarter. It also found from the tests that the non-drilling thrust and torque should be deducted from the acquired drilling data. The non-drilling torque is actually higher than that is used to overcome the shear strength is proportional to the rotation rate.

  17. Waste tank roof slab resistance to sudden loads

    SciTech Connect

    Yau, W.W.F.

    1988-03-02

    The Department of Energy has requested that the Safety Analysis Report include an analysis of a tank top collapse event due to equipment overload. The overload is defined as a 3-ton truck plunging suddenly onto the tank roof. This memorandum reports the findings of a simplified analysis of the roof structure of a Type III waste tank. Based on a simplified and conservative analysis of the roof slab of a Type III waste tank, the reinforced concrete design is resistant to the impact loading of a 3-ton truck with a safety factor of at least five against large scale inelastic deformation.

  18. 13. ONE OF TWO LATERAL ROOF TRUSSES AND ROOF SUPPORT ...

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

    13. ONE OF TWO LATERAL ROOF TRUSSES AND ROOF SUPPORT BEAMS OF SARATOGA GAS LIGHT COMPANY GASHOLDER NO. 2 HOUSE LOOKING WEST. THE WIRES AND BEAM AT RIGHT CENTER OF PHOTOGRAPH HAVE BEEN ADDED TO STABILIZE TRUSS SYSTEM - Saratoga Gas Light Company, Gasholder No. 2, Niagara Mohawk Power Corporation Substation Facility, intersection of Excelsior & East Avenues, Saratoga Springs, NY

  19. 12. CENTRAL ROOF TRUSS AND ROOF SUPPORT BEAMS OF SARATOGA ...

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

    12. CENTRAL ROOF TRUSS AND ROOF SUPPORT BEAMS OF SARATOGA GAS LIGHT COMPANY GASHOLDER NO. 2 HOUSE, LOOKING WEST. THE WIRES AND BEAM AT RIGHT OF PHOTOGRAPH HAVE BEEN ADDED TO STABILIZE TRUSS SYSTEM. - Saratoga Gas Light Company, Gasholder No. 2, Niagara Mohawk Power Corporation Substation Facility, intersection of Excelsior & East Avenues, Saratoga Springs, NY

  20. Entering the Roofing and Waterproofing Industry. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This book is one of a series of 10 units of instruction for roofing apprenticeship classes in California. It covers the following 14 topics and provides tests for them: the nature of the roofing and waterproofing industry; the apprenticeship program; apprenticeship and the public schools; collective bargaining, wages, and benefits; safety in the…

  1. EXTERIOR, ROOF, A view looking southeast from the roof toward ...

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

    EXTERIOR, ROOF, A view looking southeast from the roof toward a low wall and the west facade of a penthouse with two stacks located in the southern courtyard - Department of Energy, Mound Facility, B Building, One Mound Road, Miamisburg, Montgomery County, OH

  2. Hydrological Modelling and Parameter Identification for Green Roof

    NASA Astrophysics Data System (ADS)

    Lo, W.; Tung, C.

    2012-12-01

    Green roofs, a multilayered system covered by plants, can be used to replace traditional concrete roofs as one of various measures to mitigate the increasing stormwater runoff in the urban environment. Moreover, facing the high uncertainty of the climate change, the present engineering method as adaptation may be regarded as improper measurements; reversely, green roofs are unregretful and flexible, and thus are rather important and suitable. The related technology has been developed for several years and the researches evaluating the stormwater reduction performance of green roofs are ongoing prosperously. Many European counties, cities in the U.S., and other local governments incorporate green roof into the stormwater control policy. Therefore, in terms of stormwater management, it is necessary to develop a robust hydrologic model to quantify the efficacy of green roofs over different types of designs and environmental conditions. In this research, a physical based hydrologic model is proposed to simulate water flowing process in the green roof system. In particular, the model adopts the concept of water balance, bringing a relatively simple and intuitive idea. Also, the research compares the two methods in the surface water balance calculation. One is based on Green-Ampt equation, and the other is under the SCS curve number calculation. A green roof experiment is designed to collect weather data and water discharge. Then, the proposed model is verified with these observed data; furthermore, the parameters using in the model are calibrated to find appropriate values in the green roof hydrologic simulation. This research proposes a simple physical based hydrologic model and the measures to determine parameters for the model.

  3. Field Testing of an Unvented Roof with Fibrous Insulation, Tiles, and Vapor Diffusion Venting

    SciTech Connect

    Ueno, K.; Lstiburek, J. W.

    2016-02-01

    This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane. As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design.

  4. Green roofs for a drier world: effects of hydrogel amendment on substrate and plant water status.

    PubMed

    Savi, Tadeja; Marin, Maria; Boldrin, David; Incerti, Guido; Andri, Sergio; Nardini, Andrea

    2014-08-15

    Climate features of the Mediterranean area make plant survival over green roofs challenging, thus calling for research work to improve water holding capacities of green roof systems. We assessed the effects of polymer hydrogel amendment on the water holding capacity of a green roof substrate, as well as on water status and growth of Salvia officinalis. Plants were grown in green roof experimental modules containing 8 cm or 12 cm deep substrate (control) or substrate mixed with hydrogel at two different concentrations: 0.3 or 0.6%. Hydrogel significantly increased the substrate's water content at saturation, as well as water available to vegetation. Plants grown in 8 cm deep substrate mixed with 0.6% of hydrogel showed the best performance in terms of water status and membrane integrity under drought stress, associated to the lowest above-ground biomass. Our results provide experimental evidence that polymer hydrogel amendments enhance water supply to vegetation at the establishment phase of a green roof. In particular, the water status of plants is most effectively improved when reduced substrate depths are used to limit the biomass accumulation during early growth stages. A significant loss of water holding capacity of substrate-hydrogel blends was observed after 5 months from establishment of the experimental modules. We suggest that cross-optimization of physical-chemical characteristics of hydrogels and green roof substrates is needed to improve long term effectiveness of polymer-hydrogel blends.

  5. Retractable Roof Greenhouses and Shadehouses

    Treesearch

    Jr. Bartok

    2005-01-01

    Open-roof greenhouses provide a natural environment for plant growth when the outdoor weather is suitable and an artificial environment when it is too hot or cold. Opening the roof over the plants increases light intensity, which can help to control the growth habit, flowering, and crop timing. It also reduces electricity costs because expensive fan cooling is not...

  6. How Cool Is Your Roof?

    ERIC Educational Resources Information Center

    Fickes, Michael

    2001-01-01

    Explains a concept called cool roof that is used to reduce electricity costs for air conditioning, and also reduce the price of air conditioning units. Discusses the light reflecting capabilities of metal roofing as well as coatings that can stop leaks. (GR)

  7. How Cool Is Your Roof?

    ERIC Educational Resources Information Center

    Fickes, Michael

    2001-01-01

    Explains a concept called cool roof that is used to reduce electricity costs for air conditioning, and also reduce the price of air conditioning units. Discusses the light reflecting capabilities of metal roofing as well as coatings that can stop leaks. (GR)

  8. Measuring mine roof bolt strains

    DOEpatents

    Steblay, Bernard J.

    1986-01-01

    A mine roof bolt and a method of measuring the strain in mine roof bolts of this type are disclosed. According to the method, a flat portion on the head of the mine roof bolt is first machined. Next, a hole is drilled radially through the bolt at a predetermined distance from the bolt head. After installation of the mine roof bolt and loading, the strain of the mine roof bolt is measured by generating an ultrasonic pulse at the flat portion. The time of travel of the ultrasonic pulse reflected from the hole is measured. This time of travel is a function of the distance from the flat portion to the hole and increases as the bolt is loaded. Consequently, the time measurement is correlated to the strain in the bolt. Compensation for various factors affecting the travel time are also provided.

  9. Storm Water Retention on Three Green Roofs with Distinct Climates

    NASA Astrophysics Data System (ADS)

    Breach, P. A.; Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.; Powers, B. S. C.

    2014-12-01

    As urbanization continues to increase the impact of cities on their surrounding environments, the feasibility of implementing low-impact development such as green roofs is of increasing interest. Green roofs retain and attenuate storm water thereby reducing the load on urban sewer systems. In addition, green roofs can provide insulation and lower roof surface temperature leading to a decrease in building energy load. Green roof technology in North American urban environments remains underused, in part due to a lack of climate appropriate green roof design guidelines. The capacity of a green roof to moderate runoff depends on the storage capacity of the growing medium at the start of a rainfall event. Storage capacity is finite, which makes rapid drainage and evapotranspiration loss critical for maximizing storage capacity between subsequent storms. Here the retention and attenuation of storm events are quantified for experimental green roof sites located in three representative Canadian climates corresponding to; semiarid conditions in Calgary, Alberta, moderate conditions in London, Ontario, and cool and humid conditions in Halifax, Nova Scotia. The storage recovery and storm water retention at each site is modelled using a modified water balance approach. Components of the water balance including evapotranspiration are predicted using climate data collected from 2012 to 2014 at each of the experimental sites. During the measurement period there were over 300 precipitation events ranging from small, frequent events (< 2 mm) to a storm with a 250 year return period. The modeling approach adopted provides a tool for planners to assess the feasibility of implementing green roofs in their respective climates.

  10. Evaluation of the Lateral Performance of Roof Truss-to-Wall Connections in Light-Frame Wood Systems

    Treesearch

    Andrew DeRenzis; Vladimir Kochkin; Xiping Wang

    2012-01-01

    This testing program was designed to benchmark the performance of traditional roof systems and incrementally improved roof-to-wall systems with the goal of developing connection solutions that are optimized for performance and constructability. Nine full-size roof systems were constructed and tested with various levels and types of heel detailing to measure the lateral...

  11. Reliability Analysis of a Green Roof Under Different Storm Scenarios

    NASA Astrophysics Data System (ADS)

    William, R. K.; Stillwell, A. S.

    2015-12-01

    Urban environments continue to face the challenges of localized flooding and decreased water quality brought on by the increasing amount of impervious area in the built environment. Green infrastructure provides an alternative to conventional storm sewer design by using natural processes to filter and store stormwater at its source. However, there are currently few consistent standards available in North America to ensure that installed green infrastructure is performing as expected. This analysis offers a method for characterizing green roof failure using a visual aid commonly used in earthquake engineering: fragility curves. We adapted the concept of the fragility curve based on the efficiency in runoff reduction provided by a green roof compared to a conventional roof under different storm scenarios. We then used the 2D distributed surface water-groundwater coupled model MIKE SHE to model the impact that a real green roof might have on runoff in different storm events. We then employed a multiple regression analysis to generate an algebraic demand model that was input into the Matlab-based reliability analysis model FERUM, which was then used to calculate the probability of failure. The use of reliability analysis as a part of green infrastructure design code can provide insights into green roof weaknesses and areas for improvement. It also supports the design of code that is more resilient than current standards and is easily testable for failure. Finally, the understanding of reliability of a single green roof module under different scenarios can support holistic testing of system reliability.

  12. The effect of roofing material on the quality of harvested rainwater.

    PubMed

    Mendez, Carolina B; Klenzendorf, J Brandon; Afshar, Brigit R; Simmons, Mark T; Barrett, Michael E; Kinney, Kerry A; Kirisits, Mary Jo

    2011-02-01

    Due to decreases in the availability and quality of traditional water resources, harvested rainwater is increasingly used for potable and non-potable purposes. In this study, we examined the effect of conventional roofing materials (i.e., asphalt fiberglass shingle, Galvalume(®) metal, and concrete tile) and alternative roofing materials (i.e., cool and green) on the quality of harvested rainwater. Results from pilot-scale and full-scale roofs demonstrated that rainwater harvested from any of these roofing materials would require treatment if the consumer wanted to meet United States Environmental Protection Agency primary and secondary drinking water standards or non-potable water reuse guidelines; at a minimum, first-flush diversion, filtration, and disinfection are recommended. Metal roofs are commonly recommended for rainwater harvesting applications, and this study showed that rainwater harvested from metal roofs tends to have lower concentrations of fecal indicator bacteria as compared to other roofing materials. However, concrete tile and cool roofs produced harvested rainwater quality similar to that from the metal roofs, indicating that these roofing materials also are suitable for rainwater harvesting applications. Although the shingle and green roofs produced water quality comparable in many respects to that from the other roofing materials, their dissolved organic carbon concentrations were very high (approximately one order of magnitude higher than what is typical for a finished drinking water in the United States), which might lead to high concentrations of disinfection byproducts after chlorination. Furthermore the concentrations of some metals (e.g., arsenic) in rainwater harvested from the green roof suggest that the quality of commercial growing media should be carefully examined if the harvested rainwater is being considered for domestic use. Hence, roofing material is an important consideration when designing a rainwater catchment.

  13. Fiddling on the roof

    NASA Astrophysics Data System (ADS)

    Willcox, Norman

    2009-08-01

    I would like to pass on my experience with regard to Tim Simpson's comment on hot-water heating (June p19). I had a solar water-heating system installed on my roof here in Southern France in 2008. When I spoke to two "satisfied customers" about their systems, neither could tell me how much they saved in energy costs, and they did not seem to realize that the "auxiliary" immersion heater - which is permanently fitted on all systems, including my own - would come on whenever the temperature in the solar-heated tank dropped below the thermostat setting. This year we were well into the month of May before we could sometimes rely on the solar heat alone. I have fitted a time switch to the immersion heater and I switch it off completely when we have periods of full sunshine, but it is not easy to match the need for hot water to the possible availability.

  14. Mine roof support

    SciTech Connect

    Bower, L.R.; Scarfe, A.; Smith, J.C.

    1982-01-19

    A self-advancing, hydraulically powered mine roof support comprises a base means and double-acting hydraulic advancing ram extending in the intended direction of advance of the support in use. The cylinder of the advancing ram is located towards the forward end of the support and the piston rod of the advancing ram is located towards the rearward end of the support. A lifting ram is mounted on the support at or towards the forward end thereof and is operable on the periphery of the cylinder to lift the forward end with respect to the cylinder. The end of the cylinder remote from the piston rod is connectable to a pan of an armoured conveyor, and the advancing ram is connected to the support by an inclined link means pivotally attached to the base means and to the piston rod.

  15. Energy Performance Impacts from Competing Low-slope Roofing Choices and Photovoltaic Technologies

    NASA Astrophysics Data System (ADS)

    Nagengast, Amy L.

    With such a vast quantity of space, commercial low-slope roofs offer significant potential for sustainable roofing technology deployment. Specifically, building energy performance can be improved by installing rooftop energy technologies such as photovoltaic (PV) panels, and/or including designs such as white or green roofs instead of traditional black. This research aims to inform and support roof decisions through quantified energy performance impacts across roof choices and photovoltaic technologies. The primary dataset for this research was measured over a 16 month period (May 24, 2011 to October 13, 2012) from a large field experiment in Pittsburgh, Pennsylvania on top of a commercial warehouse with white, black and green roof sections, each with portions covered by polycrystalline photovoltaic panels. Results from the Pittsburgh experiment were extended to three different cities (San Diego, CA; Huntsville, AL; and Phoenix, AZ) chosen to represent a wide range of irradiance and temperature values. First, this research evaluated the difference in electricity production from a green-moss roof and black roof underneath photovoltaic panels to determine if the green roof's cooler air increases the panel efficiency. Second, separate studies examine 1) average hourly heat flux by month for unobstructed and shaded roof membranes 2) heat flux peak time delay, and 3) air temperature across roof types. Results of this research show green roofs slightly increased (0.8-1.5%) PV panel efficiency in temperatures approximately at or above 25° C (77°F) compared to black roofs. However in cool climates, like Pittsburgh, the roof type under the PV panels had little overall impact on PV performance when considering year round temperatures. Instead, roof decisions should place a stronger emphasis on heat flux impacts. The green roof outperformed both black and white roofs at minimizing total conductive heat flux. These heat flow values were used to develop a new, straight

  16. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts has...

  17. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts has...

  18. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts has...

  19. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts has...

  20. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... during each roof bolting cycle shall be tested during or immediately after the first row of bolts has...

  1. Green Roofs for Stormwater Runoff Control

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  2. Green Roofs for Stormwater Runoff Control

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  3. A Roof for ALMA

    NASA Astrophysics Data System (ADS)

    2007-03-01

    On 10 March, an official ceremony took place on the 2,900m high site of the Atacama Large Millimeter/submillimeter Array (ALMA) Operations Support Facility, from where the ALMA antennas will be remotely controlled. The ceremony marked the completion of the structural works, while the building itself will be finished by the end of the year. This will become the operational centre of one of the most important ground-based astronomical facilities on Earth. ESO PR Photo 13a/07 ESO PR Photo 13a/07 Cutting the Red Ribbon The ceremony, known as 'Tijerales' in Chile, is the equivalent to the 'roof-topping ceremony' that takes place worldwide, in one form or another, to celebrate reaching the highest level of a construction. It this case, the construction is the unique ALMA Operations Support Facility (OSF), located near the town of San Pedro de Atacama. "The end of this first stage represents an historic moment for ALMA," said Hans Rykaczewski, the European ALMA Project Manager. "Once completed in December 2007, this monumental building of 7,000 square metres will be one of the largest and most important astronomical operation centres in the world." ALMA, located at an elevation of 5,000m in the Atacama Desert of northern Chile, will provide astronomers with the world's most advanced tool for exploring the Universe at millimetre and submillimetre wavelengths. ALMA will detect fainter objects and be able to produce much higher-quality images at these wavelengths than any previous telescope system. The OSF buildings are designed to suit the requirements of this exceptional observatory in a remote, desert location. The facility, which will host about 100 people during operations, consists of three main buildings: the technical building, hosting the control centre of the observatory, the antenna assembly building, including four antenna foundations for testing and maintenance purposes, and the warehouse building, including mechanical workshops. Further secondary buildings are

  4. The impact of roofing material on building energy performance

    NASA Astrophysics Data System (ADS)

    Badiee, Ali

    The last decade has seen an increase in the efficient use of energy sources such as water, electricity, and natural gas as well as a variety of roofing materials, in the heating and cooling of both residential and commercial infrastructure. Oil costs, coal and natural gas prices remain high and unstable. All of these instabilities and increased costs have resulted in higher heating and cooling costs, and engineers are making an effort to keep them under control by using energy efficient building materials. The building envelope (that which separates the indoor and outdoor environments of a building) plays a significant role in the rate of building energy consumption. An appropriate architectural design of a building envelope can considerably lower the energy consumption during hot summers and cold winters, resulting in reduced HVAC loads. Several building components (walls, roofs, fenestration, foundations, thermal insulation, external shading devices, thermal mass, etc.) make up this essential part of a building. However, thermal insulation of a building's rooftop is the most essential part of a building envelope in that it reduces the incoming "heat flux" (defined as the amount of heat transferred per unit area per unit time from or to a surface) (Sadineni et al., 2011). Moreover, more than 60% of heat transfer occurs through the roof regardless of weather, since a roof is often the building surface that receives the largest amount of solar radiation per square annually (Suman, and Srivastava, 2009). Hence, an argument can be made that the emphasis on building energy efficiency has influenced roofing manufacturing more than any other building envelope component. This research project will address roofing energy performance as the source of nearly 60% of the building heat transfer (Suman, and Srivastava, 2009). We will also rank different roofing materials in terms of their energy performance. Other parts of the building envelope such as walls, foundation

  5. Aboveground storage tanks: Understanding the rules

    SciTech Connect

    Kitchen, T.; McCallion, J.

    1995-10-01

    Facility owners and operators using aboveground tanks for storing or processing hazardous wastes or oils must follow Environmental Protection Agency (EPA) or Occupational Safety and Health Administration (OSHA) regulations, or they risk heavy fines and penalties. Every facility storing more than 1320 gallons of hazardous waste or oil aboveground or more than 660 gallons in a single tank are required to have a spill prevention control and countermeasures plan. Given in the article is a table of aboveground tank standards under various agencies or acts. The subject and location of these regulations from the EPA, OSHA, Resource Conservation and Recovery Act (RCRA), Underwriter`s Laboratory (UL), the American Petroleum Institute (API), and the American Society of Mechanical Engineers (ASME) cover various aspects of tank construction and safety. Understanding and complying with the codes and regulations can be arduous, but the rewards in safety and environmental stewardship and the potential savings in fines make the effort worthwhile.

  6. Roof Weakening of Hydraulic Fracturing for Control of Hanging Roof in the Face End of High Gassy Coal Longwall Mining: A Case Study

    NASA Astrophysics Data System (ADS)

    Huang, Bingxiang; Wang, Youzhuang

    2016-09-01

    The occurence of hanging roof commonly arises in the face end of longwall coal mining under hard roof conditions. The sudden break and subsequent caving of a hanging roof could result in the extrusion of gas in the gob to the face, causing gas concentrations to rise sharply and to increase to over a safety-limited value. A series of linear fracturing-holes of 32 mm diameter were drilled into the roof of the entries with an anchor rig. According to the theory that the gob should be fully filled with the fragmentized falling roof rock, the drilling depth is determined as being 3 5 times the mining height if the broken expansion coefficient takes an empirical value. Considering the general extension range of cracks and the supporting form of the entryway, the spacing distance between two drilling holes is determined as being 1 2 times the crack's range of extension. Using a mounting pipe, a high pressure resistant sealing device of a small diameter-size was sent to the designated location for the high-pressure hydraulic fracturing of the roof rock. The hydraulic fracturing created the main hydro-fracturing crack and airfoil branch cracks in the interior of the roof-rock, transforming the roof structure and weakening the strength of the roof to form a weak plane which accelerated roof caving, and eventually induced the full caving in of the roof in time with the help of ground pressure. For holes deeper than 4 m, retreating hydraulic fracturing could ensure the uniformity of crack extension. Tested and applied at several mines in Shengdong Mining District, the highest ruptured water pressure was found to be 55 MPa, and the hanging roof at the face end was reduced in length from 12 m to less than 1 2 m. This technology has eliminated the risk of the extrusion of gas which has accumulated in the gob.

  7. Measure Guideline. Deep Energy Enclosure Retrofit for Zero Energy Ready House Flat Roofs

    SciTech Connect

    Loomis, H.; Pettit, B.

    2015-05-29

    This Measure Guideline provides design and construction information for a deep energy enclosure retrofit solution of a flat roof assembly. It describes the strategies and procedures for an exterior retrofit of a flat wood-framed roof with brick masonry exterior walls using exterior and interior (framing cavity) insulation. The approach supported in this guide could also be adapted for use with flat wood-framed roofs with wood-framed exterior walls.

  8. Measure Guideline: Deep Energy Enclosure Retrofit for Zero Energy Ready House Flat Roofs

    SciTech Connect

    Loomis, H.; Pettit, B.

    2015-05-01

    This Measure Guideline provides design and construction information for a deep energy enclosure retrofit (DEER) solution of a flat roof assembly. It describes the strategies and procedures for an exterior retrofit of a flat, wood-framed roof with brick masonry exterior walls, using exterior and interior (framing cavity) insulation. The approach supported in this guide could also be adapted for use with flat, wood-framed roofs with wood-framed exterior walls.

  9. Impact of green roofs on stormwater quality in a South Australian urban environment.

    PubMed

    Razzaghmanesh, M; Beecham, S; Kazemi, F

    2014-02-01

    Green roofs are an increasingly important component of water sensitive urban design systems and can potentially improve the quality of urban runoff. However, there is evidence that they can occasionally act as a source rather than a sink for pollutants. In this study, the water quality of the outflow from both intensive and extensive green roof systems were studied in the city of Adelaide, South Australia over a period of nine months. The aim was to examine the effects of different green roof configurations on stormwater quality and to compare this with runoff from aluminium and asphalt roofs as control surfaces. The contaminant concentrations in runoff from both intensive and extensive green roofs generally decreased during the study period. A comparison between the two types of green roof showed that except for some events for EC, TDS and chloride, the values of the parameters such as pH, turbidity, nitrate, phosphate and potassium in intensive green roof outflows were higher than in the outflows from the extensive green roofs. These concentrations were compared to local, state, national and international water quality guidelines in order to investigate the potential for outflow runoff from green roofs to be reused for potable and non-potable purposes. The study found that green roof outflow can provide an alternative water source for non-potable purposes such as urban landscape irrigation and toilet flushing. © 2013.

  10. [A review of green roof performance towards management of roof runoff].

    PubMed

    Chen, Xiao-ping; Huang, Pei; Zhou, Zhi-xiang; Gao, Chi

    2015-08-01

    Green roof has a significant influence on reducing runoff volume, delaying runoff-yielding time, reducing the peak flow and improving runoff quality. This paper addressed the related research around the world and concluded from several aspects, i.e., the definition of green roof of different types, the mechanism how green roof manages runoff quantity and quality, the ability how green roof controls roof runoff, and the influence factors of green roof toward runoff quantity and quality. Afterwards, there was a need for more future work on research of green roof toward roof runoff, i.e., vegetation selection of green roof, efficient construction model selection of green roof, the regulating characteristics of green roof on roof runoff, the value assessment of green roof on roof runoff, analysis of source-sink function of green roof on the water pollutants of roof runoff and the research on the mitigation measures of roof runoff pollution. This paper provided a guideline to develop green roofs aiming to regulating roof runoff.

  11. Soil-water fluxes modelling in a green roof

    NASA Astrophysics Data System (ADS)

    Lamera, Carlotta; Rulli, Maria Cristina; Becciu, Gianfranco; Rosso, Renzo

    2014-05-01

    Green roofs differ from a natural environment as they are on top of a building and are not connected to the natural ground; therefore it is critical that soils can drain and retain water simultaneously and that they work even in very shallow systems. The soil or growing medium used for green roofs is specifically engineered to provide the vegetation with nutrients, discharging any excess water into the drainage layer, and releasing stored water back into the substrate. In this way, medium depth and porosity plays an important role in stormwater retention and plant growth in a green roof. Due to the lack of a good understanding about the hydraulic efficiency of each green roof's layer in rainwater management, a detailed analysis of the hydrological dynamics, connected with the green roof technical design is essential in order to obtain a full characterization of the hydrologic behavior of a green roof system and its effects on the urban water cycle components. The purpose of this research is analyzing the soil-water dynamics through the different components of a green roof and modeling these processes though a detailed but clear subsurface hydrology module, based on green roof vertical soil water movement reproduction, in relation to climate forcing, basic technology components and geometric characteristics of green roof systems (thickness of the stratigraphy, soil layers and materials, vegetation typology and density). A multi-layer bucket model has been applied to examine the hydrological response of the green roof system under a temperate maritime climate, by varying the physical and geometric parameters that characterize the different components of the vegetated cover. Following a stage of validation and calibration, results confirm the suitability of the model to describe the hydrologic response of the green roof during the observed rainfall events: the discharge hydrograph profile, volume and timing, predicted by the model, matched experimental measurements

  12. Field Testing of an Unvented Roof with Fibrous Insulation, Tiles and Vapor Diffusion Venting

    SciTech Connect

    Ueno, K.; Lstiburek, J. W.

    2016-02-05

    This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane. As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design. The unvented roof had extended winter periods of 95-100% RH, and wafer (wood surrogate RH sensor) measurements indicating possible condensation; high moisture levels were concentrated at the roof ridge. In contrast, the diffusion vent roofs had drier conditions, with most peak MCs (sheathing) below 20%. In the spring, as outdoor temperatures warmed, all roofs dried well into the safe range (10% MC or less). Some roof-wall interfaces showed moderately high MCs; this might be due to moisture accumulation at the highest point in the lower attic, and/or shading of the roof by the adjacent second story. Monitoring will be continued at least through spring 2016 (another winter and spring).

  13. A Study of the Energy-Saving Potential of Metal Roofs Incorporating Dynamic Insulation Systems

    SciTech Connect

    Biswas, Kaushik; Miller, William A; Kriner, Scott; Manlove, Gary

    2013-01-01

    This article presents various metal roof configurations that were tested at Oak Ridge National Laboratory in Tennessee, U.S. between 2009 and 2013, and describes their potential for reducing the attic-generated space-conditioning loads. These roofs contained different combinations of phase-change material, rigid insulation, low emittance surface, and above-sheathing ventilation with standing-seam metal panels on top. These roofs were designed to be installed on existing roofs decks, or on top of asphalt shingles for retrofit construction. All the tested roofs showed the potential for substantial energy savings compared to an asphalt shingle roof, which was used as a control for comparison. The roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. The attics were built on top of a conditioned room. All attics were vented at the soffit and ridge. The test roofs and attics were instrumented with an array of thermocouples. Heat flux transducers were installed in the roof deck and attic floor (ceiling) to measure the heat flows through the roof and between the attic and conditioned space below. Temperature and heat flux data were collected during the heating, cooling and swing seasons over a three-year period. Data from previous years of testing have been published. Here, data from the latest roof configurations being tested in year three of the project are presented. All test roofs were highly effective in reducing the heat flows through the roof and ceiling, and in reducing the diurnal attic-temperature fluctuations.

  14. Building America Case Study: Field Testing an Unvented Roof with Fibrous Insulation and Tiles, Orlando, Florida

    SciTech Connect

    2015-11-01

    This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane. As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design. The unvented roof had extended winter periods of 95-100% RH, and wafer (wood surrogate RH sensor) measurements indicating possible condensation; high moisture levels were concentrated at the roof ridge. In contrast, the diffusion vent roofs had drier conditions, with most peak MCs (sheathing) below 20%. In the spring, as outdoor temperatures warmed, all roofs dried well into the safe range (10% MC or less). Some roof-wall interfaces showed moderately high MCs; this might be due to moisture accumulation at the highest point in the lower attic, and/or shading of the roof by the adjacent second story. Monitoring will be continued at least through spring 2016 (another winter and spring).

  15. Aboveground and belowground net primary production

    Treesearch

    Marianne K. Burke; Hal O. Liechty; Mark H. Eisenbies

    2000-01-01

    The relationship among net primary productivity (NPP), hydroperiod, and fertility in forested wetlands is poorly understood (Burke and others 1999), particularly with respect to belowground NPP (Megonigal and others 1997). Although some researchers have studied aboveground and belowground primary production in depressional, forested wetland systems, e.g., Day and...

  16. Reference electrodes for aboveground storage tanks

    SciTech Connect

    Ansuini, F.J.; Dimond, J.R.

    1995-12-31

    This paper discusses several factors affecting the reference potential established by copper/copper sulfate and silver/silver chloride reference electrodes. Guidelines for using references in aboveground storage tank applications are presented and some causes of misleading readings are discussed.

  17. Aboveground storage tanks -- Better safe than sorry

    SciTech Connect

    Rizzo, J.A.

    1995-12-31

    With the 1988 promulgation of the comprehensive Resource Conservation and Recovery Act (RCRA) regulations for underground storage of petroleum and hazardous substances, many existing underground storage tank (UST) owners have been considering making the move to aboveground storage. While on the surface, this may appear to be the cure-all to avoiding the underground leakage dilemma, there are many other new and different issues to consider with aboveground storage. The greatest misconception is that by storing materials above ground, there is no risk of subsurface environmental problems. It should be noted that with aboveground storage tank (AGST) systems, there is still considerable risk of environmental contamination, either by the failure of onground tank bottoms or the spillage of product onto the ground surface where it subsequently finds its way to the ground water. In addition, there are added safety concerns that must be addressed. So what are the other specific areas of concern besides environmental to be addressed when making the decision between underground and aboveground tanks? The primary issues that will be addressed in this presentation are: safety; product losses; cost comparison of UST vs AGSTs; space availability/accessibility; precipitation handling; aesthetics and security; and existing and pending regulations.

  18. Developing resilient green roofs in a dry climate.

    PubMed

    Razzaghmanesh, M; Beecham, S; Brien, C J

    2014-08-15

    Living roofs are an emerging green infrastructure technology that can potentially be used to ameliorate both climate change and urban heat island effects. There is not much information regarding the design of green roofs for dry climates and so the aim of this study was to develop low maintenance and unfertilized green roofs for a dry climate. This paper describes the effects of four important elements of green roofs namely slope, depth, growing media and plant species and their possible interactions in terms of plant growth responses in a dry climate. Sixteen medium-scale green roofs were set up and monitored during a one year period. This experiment consisted of twelve vegetated platforms and four non-vegetated platforms as controls. The design for the experiment was a split-split-plot design in which the factors Slope (1° and 25°) and Depth (100mm, 300 mm) were randomized to the platforms (main plots). Root depth and volume, average height of plants, final dry biomass and ground cover, relative growth rate, final dry shoot-root ratio, water use efficiency and leaf succulence were studied during a twelve month period. The results showed little growth of the plants in media type A, whilst the growth was significant in both media types B and C. On average, a 90% survival rate of plants was observed. Also the growth indices indicated that some plants can grow efficiently in the harsh environment created by green roofs in a dry climate. The root growth pattern showed that retained water in the drainage layer is an alternative source of water for plants. It was also shown that stormwater can be used as a source of irrigation water for green roofs during six months of the year at the study site. In summary, mild sloping intensive systems containing media type C and planted with either Chrysocephalum apiculatum or Disphyma crassifolium showed the best performance.

  19. Plant species and functional group combinations affect green roof ecosystem functions.

    PubMed

    Lundholm, Jeremy; Macivor, J Scott; Macdougall, Zachary; Ranalli, Melissa

    2010-03-12

    Green roofs perform ecosystem services such as summer roof temperature reduction and stormwater capture that directly contribute to lower building energy use and potential economic savings. These services are in turn related to ecosystem functions performed by the vegetation layer such as radiation reflection and transpiration, but little work has examined the role of plant species composition and diversity in improving these functions. We used a replicated modular extensive (shallow growing- medium) green roof system planted with monocultures or mixtures containing one, three or five life-forms, to quantify two ecosystem services: summer roof cooling and water capture. We also measured the related ecosystem properties/processes of albedo, evapotranspiration, and the mean and temporal variability of aboveground biomass over four months. Mixtures containing three or five life-form groups, simultaneously optimized several green roof ecosystem functions, outperforming monocultures and single life-form groups, but there was much variation in performance depending on which life-forms were present in the three life-form mixtures. Some mixtures outperformed the best monocultures for water capture, evapotranspiration, and an index combining both water capture and temperature reductions. Combinations of tall forbs, grasses and succulents simultaneously optimized a range of ecosystem performance measures, thus the main benefit of including all three groups was not to maximize any single process but to perform a variety of functions well. Ecosystem services from green roofs can be improved by planting certain life-form groups in combination, directly contributing to climate change mitigation and adaptation strategies. The strong performance by certain mixtures of life-forms, especially tall forbs, grasses and succulents, warrants further investigation into niche complementarity or facilitation as mechanisms governing biodiversity-ecosystem functioning relationships in green

  20. Plant Species and Functional Group Combinations Affect Green Roof Ecosystem Functions

    PubMed Central

    Lundholm, Jeremy; MacIvor, J. Scott; MacDougall, Zachary; Ranalli, Melissa

    2010-01-01

    Background Green roofs perform ecosystem services such as summer roof temperature reduction and stormwater capture that directly contribute to lower building energy use and potential economic savings. These services are in turn related to ecosystem functions performed by the vegetation layer such as radiation reflection and transpiration, but little work has examined the role of plant species composition and diversity in improving these functions. Methodology/Principal Findings We used a replicated modular extensive (shallow growing- medium) green roof system planted with monocultures or mixtures containing one, three or five life-forms, to quantify two ecosystem services: summer roof cooling and water capture. We also measured the related ecosystem properties/processes of albedo, evapotranspiration, and the mean and temporal variability of aboveground biomass over four months. Mixtures containing three or five life-form groups, simultaneously optimized several green roof ecosystem functions, outperforming monocultures and single life-form groups, but there was much variation in performance depending on which life-forms were present in the three life-form mixtures. Some mixtures outperformed the best monocultures for water capture, evapotranspiration, and an index combining both water capture and temperature reductions. Combinations of tall forbs, grasses and succulents simultaneously optimized a range of ecosystem performance measures, thus the main benefit of including all three groups was not to maximize any single process but to perform a variety of functions well. Conclusions/Significance Ecosystem services from green roofs can be improved by planting certain life-form groups in combination, directly contributing to climate change mitigation and adaptation strategies. The strong performance by certain mixtures of life-forms, especially tall forbs, grasses and succulents, warrants further investigation into niche complementarity or facilitation as mechanisms

  1. Linking evapotranspiration to stormwater reduction and attenuation in green roofs in Calgary, Alberta

    NASA Astrophysics Data System (ADS)

    Breach, P. A.; Robinson, C. E.; Voogt, J. A.; Smart, C. C.; O'Carroll, D. M.

    2013-12-01

    Green roofs have been used for centuries to insulate buildings and beautify urban environments. European countries, especially Germany, have adopted green roofs use in modern buildings, helping raise awareness of their many potential benefits. Green roofs have been shown to: effectively reduce and filter stormwater thereby decreasing the burden on urban sewer systems; provide insulation and lower roof surface temperature leading to a decrease in building energy load and reduced sensible heat flux to the urban atmosphere; and to extend the life of a roof by decreasing the temperature fluctuations which cause roof damage. Given that green buildings can mitigate against the negative impacts of storm water runoff and reduce the heating and cooling demands, use of green roofs in Canada might prove extremely beneficial due to our intense climate. However, the implementation of green roofs in North American urban environments remains underused, in part due to a lack of climate appropriate green roof design guidelines that are supported by scientific understanding of their performance in North American climates. The capacity of a green roof installation to moderate runoff depends on the storage capacity of the rooting medium at the start of the rainfall event which in turn is constrained by roof loading. The influence of medium depth is investigated through comparison to 15 cm and 10cm deep planting modules. Storage capacity has a finite limit, making rapid drainage and evapotranspiration loss essential to restore the retardation of a subsequent storm. Sustaining live plant cover requires avoidance of saturated conditions and retention of minimum soil moisture levels. These limits constrain the design options with distinctive climatic stresses. Here the performance of experimental green roof modules is investigated under particularly high climatic stressing at Calgary Alberta Canada. 10 cm modules show rapid drying to unacceptably low residual moisture content, whereas 15

  2. Empirically Derived Strength of Residential Roof Structures for Solar Installations.

    SciTech Connect

    Dwyer, Stephen F.; Sanchez, Alfred; Campos, Ivan A.; Gerstle, Walter H.

    2014-12-01

    Engineering certification for the installation of solar photovoltaic (PV) modules on wood roofs is often denied because existing wood roofs do not meet structural design codes. This work is intended to show that many roofs are actually sufficiently strong given the conservatism in codes, documented allowable strengths, roof structure system effects, and beam composite action produced by joist-sheathing interaction. This report provides results from a testing program to provide actual load carrying capacity of residential rooftops. The results reveal that the actual load carrying capacity of structural members and systems tested are significantly stronger than allowable loads provided by the International Residential Code (IRC 2009) and the national structural code found in Minimum Design Loads for Buildings and Other Structures (ASCE 7-10). Engineering analysis of residential rooftops typically ignores the system affects and beam composite action in determining rooftop stresses given a potential PV installation. This extreme conservatism combined with conservatism in codes and published allowable stress values for roof building materials (NDS 2012) lead to the perception that well built homes may not have adequate load bearing capacity to enable a rooftop PV installation. However, based on the test results presented in this report of residential rooftop structural systems, the actual load bearing capacity is several times higher than published values (NDS 2012).

  3. Roof Management Program--Three Steps to Success.

    ERIC Educational Resources Information Center

    Young, D. B., Jr.

    1987-01-01

    A roof management program protects the capital investment of a new roof. Steps to create a program are (1) assemble roof information files, (2) implement a roof inspection program with periodic inspection, and (3) establish maintenance scheduling and implementation. (MLF)

  4. Roof selection for rainwater harvesting: quantity and quality assessments in Spain.

    PubMed

    Farreny, Ramon; Morales-Pinzón, Tito; Guisasola, Albert; Tayà, Carlota; Rieradevall, Joan; Gabarrell, Xavier

    2011-05-01

    Roofs are the first candidates for rainwater harvesting in urban areas. This research integrates quantitative and qualitative data of rooftop stormwater runoff in an urban Mediterranean-weather environment. The objective of this paper is to provide criteria for the roof selection in order to maximise the availability and quality of rainwater. Four roofs have been selected and monitored over a period of 2 years (2008-2010): three sloping roofs - clay tiles, metal sheet and polycarbonate plastic - and one flat gravel roof. The authors offer a model for the estimation of the runoff volume and the initial abstraction of each roof, and assess the physicochemical contamination of roof runoff. Great differences in the runoff coefficient (RC) are observed, depending mostly on the slope and the roughness of the roof. Thus, sloping smooth roofs (RC>0.90) may harvest up to about 50% more rainwater than flat rough roofs (RC=0.62). Physicochemical runoff quality appears to be generally better than the average quality found in the literature review (conductivity: 85.0 ± 10.0 μS/cm, total suspended solids: 5.98 ± 0.95 mg/L, total organic carbon: 11.6 ± 1.7 mg/L, pH: 7.59 ± 0.07 upH). However, statistically significant differences are found between sloping and flat rough roofs for some parameters (conductivity, total organic carbon, total carbonates system and ammonium), with the former presenting better quality in all parameters (except for ammonium). The results have an important significance for local governments and urban planners in the (re)design of buildings and cities from the perspective of sustainable rainwater management. The inclusion of criteria related to the roof's slope and roughness in city planning may be useful to promote rainwater as an alternative water supply while preventing flooding and water scarcity.

  5. Learning-based roof style classification in 2D satellite images

    NASA Astrophysics Data System (ADS)

    Zang, Andi; Zhang, Xi; Chen, Xin; Agam, Gady

    2015-05-01

    Accurately recognizing building roof style leads to a much more realistic 3D building modeling and rendering. In this paper, we propose a novel system for image based roof style classification using machine learning technique. Our system is capable of accurately recognizing four individual roof styles and a complex roof which is composed of multiple parts. We make several novel contributions in this paper. First, we propose an algorithm that segments a complex roof to parts which enable our system to recognize the entire roof based on recognition of each part. Second, to better characterize a roof image, we design a new feature extracted from a roof edge image. We demonstrate that this feature has much better performance compared to recognition results generated by Histogram of Oriented Gradient (HOG), Scale-invariant Feature Transform (SIFT) and Local Binary Patterns (LBP). Finally, to generate a classifier, we propose a learning scheme that trains the classifier using both synthetic and real roof images. Experiment results show that our classifier performs well on several test collections.

  6. High Efficiency Solar Integrated Roof Membrane Product

    SciTech Connect

    Partyka, Eric; Shenoy, Anil

    2013-05-15

    This project was designed to address the Solar Energy Technology Program objective, to develop new methods to integrate photovoltaic (PV) cells or modules within a building-integrated photovoltaic (BIPV) application that will result in lower installed cost as well as higher efficiencies of the encapsulated/embedded PV module. The technology assessment and development focused on the evaluation and identification of manufacturing technologies and equipment capable of producing such low-cost, high-efficiency, flexible BIPV solar cells on single-ply roofing membranes.

  7. Comparison of Software Models for Energy Savings from Cool Roofs

    SciTech Connect

    New, Joshua Ryan; Miller, William A; Huang, Yu; Levinson, Ronnen

    2014-01-01

    A web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. This tool employs modern web technologies, usability design, and national average defaults as an interface to annual simulations of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim in order to provide estimated annual energy and cost savings. In addition to cool reflective roofs, RSC simulates multiple roof and attic configurations including different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. A base case and energy-efficient alternative can be compared side-by-side to estimate monthly energy. RSC was benchmarked against field data from demonstration homes in Ft. Irwin, California; while cooling savings were similar, heating penalty varied significantly across different simulation engines. RSC results reduce cool roofing cost-effectiveness thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC s projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus, and presents preliminary analyses. RSC s algorithms for capturing radiant heat transfer and duct interaction in the attic assembly are considered major contributing factors to increased cooling savings and heating penalties. Comparison to previous simulation-based studies, analysis on the force multiplier of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model are included.

  8. IDENTIFYING ROOF FALL PREDICTORS USING FUZZY CLASSIFICATION

    SciTech Connect

    Bertoncini, C. A.; Hinders, M. K.

    2010-02-22

    Microseismic monitoring involves placing geophones on the rock surfaces of a mine to record seismic activity. Classification of microseismic mine data can be used to predict seismic events in a mine to mitigate mining hazards, such as roof falls, where properly bolting and bracing the roof is often an insufficient method of preventing weak roofs from destabilizing. In this study, six months of recorded acoustic waveforms from microseismic monitoring in a Pennsylvania limestone mine were analyzed using classification techniques to predict roof falls. Fuzzy classification using features selected for computational ease was applied on the mine data. Both large roof fall events could be predicted using a Roof Fall Index (RFI) metric calculated from the results of the fuzzy classification. RFI was successfully used to resolve the two significant roof fall events and predicted both events by at least 15 hours before visual signs of the roof falls were evident.

  9. Cathodic protection maintenance for aboveground storage tanks

    SciTech Connect

    Koszewski, L.

    1995-12-31

    Cathodic protection systems are utilized to mitigate corrosion on the external bottom surfaces of aboveground storage tanks (ASTs). Cathodic protection systems should be part of a preventative maintenance program to minimize in-service failures. A good maintenance program will permit determination of continuous adequate cathodic protection of ASTs, through sustained operation and also provide the opportunity to detect cathodic protection system malfunctions, through periodic observations and testing.

  10. Self advancing mine roof supports

    SciTech Connect

    Seddon, J.; Jones, F.

    1985-03-19

    A self-advancing mine-roof-support for use in or aligned with a main roadway or gate has a floor-engaging part and a roof engaging part spaced apart by extensible load-bearing prop or jack means, and engagement means for a face-conveyor and a transversely acting transfer conveyor whereby their relative positions are constrained to facilitate discharge of mineral from one conveyor to the other. The engagement means for the face conveyor comprises sliding anchor beams that assure maintenance of the relative attitudes of the support and the face conveyor and the transfer conveyor is held fore and aft of the support.

  11. Common Roofing and Waterproofing Materials and Equipment. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This publication on common roofing and waterproofing materials and equipment is one of a series of units of instruction for roofing apprenticeship classes. The workbook portion is divided into eight topics: production of bitumens and asphalt roofing materials, built-up materials and adhesives, asphalt products and rigid roofing materials,…

  12. Roofing: Workbook and Tests. Common Roofing and Waterproofing Materials and Equipment.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This workbook on materials and equipment is one of a series of nine individual units of instruction for roofing apprenticeship classes in California. The workbook covers eight topics: production of bitumens and asphaltic roofing materials; built-up roofing materials and adhesives; asphaltic products and rigid roofing materials; elastomeric and…

  13. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects to...

  14. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 16 2014-07-01 2014-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects to...

  15. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 16 2013-07-01 2013-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects to...

  16. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects to...

  17. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  18. Common Roofing and Waterproofing Materials and Equipment. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This publication on common roofing and waterproofing materials and equipment is one of a series of units of instruction for roofing apprenticeship classes. The workbook portion is divided into eight topics: production of bitumens and asphalt roofing materials, built-up materials and adhesives, asphalt products and rigid roofing materials,…

  19. Cold-Applied Roofing Systems and Waterproofing and Dampproofing. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    Brown, Arthur

    This workbook for students in California roofing apprenticeship programs provides information for classroom work in the area of cold-applied roofing systems and waterproofing and dampproofing. Eight topics are covered: introduction to cold-applied roofing systems and waterproofing and dampproofing, tools and equipment used in cold-applied roofing,…

  20. The Effects of Infrared-Blocking Pigments and Deck Venting on Stone-Coated Metal Residential Roofs

    SciTech Connect

    Miller, William A

    2006-01-01

    Field data show that stone-coated metal shakes and S-mission tile, which exploit the use of infraredblocking color pigments (IrBCPs), along with underside venting reduce the heat flow penetrating the conditioned space of a residence by 70% compared with the amount of heat flow penetrating roofs with conventional asphalt shingles. Stone-coated metal roof products are typically placed on battens and counter-battens and nailed through the battens to the roof deck. The design provides venting on the underside of the metal roof that reduces the heat flow penetrating a home. The Metal Construction Association (MCA) and its affiliate members installed stone-coated metal roofs with shake and S-mission tile profiles and a painted metal shake roof on a fully instrumented attic test assembly at Oak Ridge National Laboratory (ORNL). Measurements of roof, deck, attic, and ceiling temperatures; heat flows; solar reflectance; thermal emittance; and ambient weather were recorded for each of the test roofs and also for an adjacent attic cavity covered with a conventional pigmented and direct nailed asphalt shingle roof. All attic assemblies had ridge and soffit venting; the ridge was open to the underside of the stone-coated metal roofs. A control assembly with a conventional asphalt shingle roof was used for comparing deck and ceiling heat transfer rates.

  1. Roofing Workbook and Tests: Entering the Roofing and Waterproofing Industry.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Vocational Education Services.

    This document is one of a series of nine individual units of instruction for use in roofing apprenticeship classes in California. The unit consists of a workbook and test, perforated for student use. Fourteen topics are covered in the workbook and corresponding multiple-choice tests. For each topic, objectives, information sheets, and study…

  2. Sloped Roof Conversions for Small, Flat-Roof Buildings.

    DTIC Science & Technology

    1984-12-01

    co solve other, unrelated Table 5 List of Contacts Involved in Roof Conversion Projects California AEP-Span, San Diego Florida Duval County...Survlvablllty Section, CCB-CPS Infrastructure Branch, LANDA HQ UsaUCOH 09128 ATTN: ECJ 4/7-LOE Fort Belvoir, VA 22060 (7) ATTN

  3. Roofing Materials Assessment: Investigation of Five Metals in Runoff from Roofing Materials.

    PubMed

    Winters, Nancy; Granuke, Kyle; McCall, Melissa

    2015-09-01

    To assess the contribution of five toxic metals from new roofing materials to stormwater, runoff was collected from 14 types of roofing materials and controls during 20 rain events and analyzed for metals. Many of the new roofing materials evaluated did not show elevated metals concentrations in the runoff. Runoff from several other roofing materials was significantly higher than the controls for arsenic, copper, and zinc. Notably, treated wood shakes released arsenic and copper, copper roofing released copper, PVC roofing released arsenic, and Zincalume® and EPDM roofing released zinc. For the runoff from some of the roofing materials, metals concentrations decreased significantly over an approximately one-year period of aging. Metals concentrations in runoff were demonstrated to depend on a number of factors, such as roofing materials, age of the materials, and climatic conditions. Thus, application of runoff concentrations from roofing materials to estimate basin-wide releases should be undertaken cautiously.

  4. GREEN ROOFS — A GROWING TREND

    EPA Science Inventory

    One of the most interesting stormwater control systems under evaluation by EPA are “green roofs”. Green roofs are vegetative covers applied to building roofs to slow, or totally absorb, rainfall runoff during storms. While the concept of over-planted roofs is very ancient, the go...

  5. GREEN ROOFS — A GROWING TREND

    EPA Science Inventory

    One of the most interesting stormwater control systems under evaluation by EPA are “green roofs”. Green roofs are vegetative covers applied to building roofs to slow, or totally absorb, rainfall runoff during storms. While the concept of over-planted roofs is very ancient, the go...

  6. Guidelines for Inspecting Your Roof Systems.

    ERIC Educational Resources Information Center

    Watkins, Daniel L.

    2003-01-01

    Provides guidelines for inspecting the roof of a facility. Suggests that periodic roof inspections should be performed on a quarterly or semi-annual basis and after severe storms. Proactively identifying potential problem areas is the best defense against roof leaks. (SLD)

  7. Keys to a Successful Roofing System.

    ERIC Educational Resources Information Center

    Kornahrens, Rob

    1999-01-01

    Provides advice on successfully managing an educational facility's roofing system by first getting the best roofing system possible, then undertaking regular precautionary measures to assure its peak performance. Specific points address such areas as choosing a roofing contractor, hiring a professional to create specifications, monitoring…

  8. Analytical study of residential building with reflecting roofs

    SciTech Connect

    Zarr, R.R.

    1998-10-01

    This report presents an analysis of the effect of roof solar reflectance on the annual heating (cooling) loads, peak heating (cooling) loads, and roof temperatures of the residential buildings. The annual heating (cooling) loads, peak heating (cooling) loads, and exterior roof temperatures for a small compact ranch house are computed using the Thermal Analysis Research Program (TARP). The residential models, with minor modifications in the thermal envelope for different locations, are subjected to hourly weather data for one year compiled in the Weather Year for Energy Calculation (WYEC) for in the following locations: Birmingham, Alabama; Bismarck, North Dakota; Miami, Florida; Phoenix, Arizona; Portland, Maine; and, Washington, D.C. Building loads have been determined for a full factorial experimental design that varies the following parameters of the residential model: solar reflectance of the roof, ceiling thermal resistance, attic ventilation, and attic mass framing area. The computed results for annual heating (cooling) loads and peak heating (cooling) loads are illustrated graphically, both globally for all cities and locally for each geographic location. The effect of peak parameter is ranked (highest to lowest) for effect on annual heating and cooling loads, and peak heating and cooling loads. A parametric study plots the building loads as a function of roof solar reflectance for different levels of ceiling thermal resistances and for each geographic location.

  9. The green roof dilemma - discussion of Francis and Lorimer (2011).

    PubMed

    Henry, Alexandre; Frascaria-Lacoste, Nathalie

    2012-08-15

    Urban ecosystems are the most complex mosaics of vegetative land cover that can be found. In a recent paper, Francis and Lorimer (2011) evaluated the reconciliation potential of living roofs and walls. For these authors, these two techniques for habitat improvement have strong potential for urban reconciliation ecology. However they have some ecological and societal limitations such as the physical extreme environmental characteristics, the monetary investment and the cultural perceptions of urban nature. We are interested in their results and support their conclusions. However, for a considerable time, green roofs have been designed to provide urban greenery for buildings and the green roof market has only focused on extensive roof at a restricted scale within cities. Thus, we have strong doubts about the relevance of their use as possible integrated elements of the network. Furthermore, without dynamic progress in research and the implementation of well-thought-out policies, what will be the real capital gain from green roofs with respect to land-use complementation in cities? If we agree with Francis and Lorimer (2011) considering that urban reconciliation ecology between nature and citizens is a current major challenge, then "adaptive collaborative management" is a fundamental requirement. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. A parametric study of the thermal performance of green roofs in different climates through energy modeling

    NASA Astrophysics Data System (ADS)

    Mukherjee, Sananda

    In recent years, there has been great interest in the potential of green roofs as an alternative roofing option to reduce the energy consumed by individual buildings as well as mitigate large scale urban environmental problems such as the heat island effect. There is a widespread recognition and a growing literature of measured data that suggest green roofs can reduce building energy consumption. This thesis investigates the potential of green roofs in reducing the building energy loads and focuses on how the different parameters of a green roof assembly affect the thermal performance of a building. A green roof assembly is modeled in Design Builder- a 3D graphical design modeling and energy use simulation program (interface) that uses the EnergyPlus simulation engine, and the simulated data set thus obtained is compared to field experiment data to validate the roof assembly model on the basis of how accurately it simulates the behavior of a green roof. Then the software is used to evaluate the thermal performance of several green roof assemblies under three different climate types, looking at the whole building energy consumption. For the purpose of this parametric simulation study, a prototypical single story small office building is considered and one parameter of the green roof is altered for each simulation run in order to understand its effect on building's energy loads. These parameters include different insulation thicknesses, leaf area indices (LAI) and growing medium or soil depth, each of which are tested under the three different climate types. The energy use intensities (EUIs), the peak and annual heating and cooling loads resulting from the use of these green roof assemblies are compared with each other and to a cool roof base case to determine the energy load reductions, if any. The heat flux through the roof is also evaluated and compared. The simulation results are then organized and finally presented as a decision support tool that would

  11. Roof temperatures in simulated attics

    Treesearch

    J. E. Winandy; R. Beaumont

    The degradation of wood treated with fire retardant (FR) chemicals in roof systems is a problem of major national significance. Understanding of this phenomenon is limited by lack of information on how the performance of FR-treated wood in the laboratory correlates to that of FR-treated wood in the field. In this study, five outdoor field exposure chambers were...

  12. Reducing roof fall accidents on retreat mining sections

    SciTech Connect

    Mark, C.; Zelanko, J.C.

    2005-12-15

    Pillar recovery continues to be one of the most hazardous activities in underground mining. Global stability, achieved through proper pillar design, is a necessary prerequisite for safe pillar recovery. Local stability means preventing roof falls in the working area. It is achieved by minimizing the 'risk factors' described in this paper. Roof Control Plans developed at each underground coal mine often address both engineering parameters and human behavior issues. These plans are essential to all mining activities, but nowhere are they more important than in pillar recovery. Pillaring leaves little tolerance for error, and mistakes can be deadly. Roof Control Plans must be carefully drawn up to address site-specific conditions, and then carefully implemented and followed. Miners and foremen involved in pillar extraction should be trained to know and understand the plan prior to beginning retreat mining. More details can be found at www.cdc.gov/niosh/mining/pubs/pdfs/rtrog.pdf. 3 figs.

  13. Quantitative analysis on the urban flood mitigation effect by the extensive green roof system.

    PubMed

    Lee, J Y; Moon, H J; Kim, T I; Kim, H W; Han, M Y

    2013-10-01

    Extensive green-roof systems are expected to have a synergetic effect in mitigating urban runoff, decreasing temperature and supplying water to a building. Mitigation of runoff through rainwater retention requires the effective design of a green-roof catchment. This study identified how to improve building runoff mitigation through quantitative analysis of an extensive green-roof system. Quantitative analysis of green-roof runoff characteristics indicated that the extensive green roof has a high water-retaining capacity response to rainfall of less than 20 mm/h. As the rainfall intensity increased, the water-retaining capacity decreased. The catchment efficiency of an extensive green roof ranged from 0.44 to 0.52, indicating reduced runoff comparing with efficiency of 0.9 for a concrete roof. Therefore, extensive green roofs are an effective storm water best-management practice and the proposed parameters can be applied to an algorithm for rainwater-harvesting tank design. © 2013 Elsevier Ltd. All rights reserved.

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

    ERIC Educational Resources Information Center

    Brown, Arthur

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

  15. 24 CFR 3280.402 - Test procedure for roof trusses.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Nondestructive test procedure—(1) Dead load plus live load. (i) Noting figure A-1, measure and record initial... the truss equal to the full dead load of roof and ceiling. Measure and record deflections. (iii) Maintaining the dead load, add live load in approximate 1/4 design live load increments. Measure the...

  16. 24 CFR 3280.402 - Test procedure for roof trusses.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Nondestructive test procedure—(1) Dead load plus live load. (i) Noting figure A-1, measure and record initial... the truss equal to the full dead load of roof and ceiling. Measure and record deflections. (iii) Maintaining the dead load, add live load in approximate 1/4 design live load increments. Measure...

  17. Habitat connectivity shapes urban arthropod communities: the key role of green roofs.

    PubMed

    Braaker, S; Ghazoul, J; Obrist, M K; Moretti, M

    2014-04-01

    that eventually even communities of low-mobility species become connected. Furthermore, improving the design of green roofs (composition and configuration of vegetation and soil types) could enhance the ecological value, particularly for low-mobility species.

  18. Two-dimensional modeling of water and heat fluxes in green roof substrates

    NASA Astrophysics Data System (ADS)

    Suarez, F. I.; Sandoval, V. P.

    2016-12-01

    Due to public concern towards sustainable development, greenhouse gas emissions and energy efficiency, green roofs have become popular in the last years. Green roofs integrate vegetation into infrastructures to reach additional benefits that minimize negative impacts of the urbanization. A properly designed green roof can reduce environmental pollution, noise levels, energetic requirements or surface runoff. The correct performance of green roofs depends on site-specific conditions and on each component of the roof. The substrate and the vegetation layers strongly influence water and heat fluxes on a green roof. The substrate is an artificial media that has an improved performance compared to natural soils as it provides critical resources for vegetation survival: water, nutrients, and a growing media. Hence, it is important to study the effects of substrate properties on green roof performance. The objective of this work is to investigate how the thermal and hydraulic properties affect the behavior of a green roof through numerical modeling. The substrates that were investigated are composed by: crushed bricks and organic soil (S1); peat with perlite (S2); crushed bricks (S3); mineral soil with tree leaves (S4); and a mixture of topsoil and mineral soil (S5). The numerical model utilizes summer-arid meteorological information to evaluate the performance of each substrate. Results show that the area below the water retention curve helps to define the substrate that retains more water. In addition, the non-linearity of the water retention curve can increment the water needed to irrigate the roof. The heat propagation through the roof depends strongly on the hydraulic behavior, meaning that a combination of a substrate with low thermal conductivity and more porosity can reduce the heat fluxes across the roof. Therefore, it can minimize the energy consumed of an air-conditioner system.

  19. Life-cycle cost-benefit analysis of extensive vegetated roof systems.

    PubMed

    Carter, Timothy; Keeler, Andrew

    2008-05-01

    The built environment has been a significant cause of environmental degradation in the previously undeveloped landscape. As public and private interest in restoring the environmental integrity of urban areas continues to increase, new construction practices are being developed that explicitly value beneficial environmental characteristics. The use of vegetation on a rooftop--commonly called a green roof--as an alternative to traditional roofing materials is an increasingly utilized example of such practices. The vegetation and growing media perform a number of functions that improve environmental performance, including: absorption of rainfall, reduction of roof temperatures, improvement in ambient air quality, and provision of urban habitat. A better accounting of the green roof's total costs and benefits to society and to the private sector will aid in the design of policy instruments and educational materials that affect individual decisions about green roof construction. This study uses data collected from an experimental green roof plot to develop a benefit cost analysis (BCA) for the life cycle of extensive (thin layer) green roof systems in an urban watershed. The results from this analysis are compared with a traditional roofing scenario. The net present value (NPV) of this type of green roof currently ranges from 10% to 14% more expensive than its conventional counterpart. A reduction of 20% in green roof construction cost would make the social NPV of the practice less than traditional roof NPV. Considering the positive social benefits and relatively novel nature of the practice, incentives encouraging the use of this practice in highly urbanized watersheds are strongly recommended.

  20. Aboveground pipeline response to random ground motion

    SciTech Connect

    Banerji, P.; Ghosh, A.

    1995-12-31

    Response of two types of aboveground pipelines--rigid, segmented pipelines, and flexible, continuous pipelines--to random ground motion are studied in this paper. The emphasis is on studying the effect of pipeline system parameters on its response. It is seen that pipe parameters, except for the pipe span, affect system response negligibly. Pier height and flexibility, and foundation-soil flexibility, however, affect response significantly. Furthermore, for practical situations, pipe and pier responses are decoupled, and the pier, therefore, behaves essentially as a point structure that is not affected by spatial variation of ground motion.

  1. The NDT perspective on aboveground storage tanks

    SciTech Connect

    Rusing, J.E. )

    1994-07-01

    This article is an overview of above-ground storage tank (AST) in the US. Tank numbers, size, construction, location, and material stored will be discussed. The present environment for nondestructive testing (NDT) technologies will also be explored. The present aging storage tank population presents an opportunity for the NDT community to provide the necessary technologies to verify storage tank reliability in a cost beneficial manner. The paper first explains terminology, definitions, and standards, then discusses estimates of the AST population, causes of petroleum spillage, and how the industry tests for leaks.

  2. Wind Tunnel Tests for Wind Pressure Distribution on Gable Roof Buildings

    PubMed Central

    2013-01-01

    Gable roof buildings are widely used in industrial buildings. Based on wind tunnel tests with rigid models, wind pressure distributions on gable roof buildings with different aspect ratios were measured simultaneously. Some characteristics of the measured wind pressure field on the surfaces of the models were analyzed, including mean wind pressure, fluctuating wind pressure, peak negative wind pressure, and characteristics of proper orthogonal decomposition results of the measured wind pressure field. The results show that extremely high local suctions often occur in the leading edges of longitudinal wall and windward roof, roof corner, and roof ridge which are the severe damaged locations under strong wind. The aspect ratio of building has a certain effect on the mean wind pressure coefficients, and the effect relates to wind attack angle. Compared with experimental results, the region division of roof corner and roof ridge from AIJ2004 is more reasonable than those from CECS102:2002 and MBMA2006.The contributions of the first several eigenvectors to the overall wind pressure distributions become much bigger. The investigation can offer some basic understanding for estimating wind load distribution on gable roof buildings and facilitate wind-resistant design of cladding components and their connections considering wind load path. PMID:24082851

  3. Wind tunnel tests for wind pressure distribution on gable roof buildings.

    PubMed

    Jing, Xiao-kun; Li, Yuan-qi

    2013-01-01

    Gable roof buildings are widely used in industrial buildings. Based on wind tunnel tests with rigid models, wind pressure distributions on gable roof buildings with different aspect ratios were measured simultaneously. Some characteristics of the measured wind pressure field on the surfaces of the models were analyzed, including mean wind pressure, fluctuating wind pressure, peak negative wind pressure, and characteristics of proper orthogonal decomposition results of the measured wind pressure field. The results show that extremely high local suctions often occur in the leading edges of longitudinal wall and windward roof, roof corner, and roof ridge which are the severe damaged locations under strong wind. The aspect ratio of building has a certain effect on the mean wind pressure coefficients, and the effect relates to wind attack angle. Compared with experimental results, the region division of roof corner and roof ridge from AIJ2004 is more reasonable than those from CECS102:2002 and MBMA2006.The contributions of the first several eigenvectors to the overall wind pressure distributions become much bigger. The investigation can offer some basic understanding for estimating wind load distribution on gable roof buildings and facilitate wind-resistant design of cladding components and their connections considering wind load path.

  4. Photovoltaic Roof Heat Flux

    NASA Astrophysics Data System (ADS)

    Samady, Mezhgan Frishta

    Solar panels were mounted with different designs onto 1:800 scale building models while temperature and radiation were measured. While there have been other studies aimed at finding the optimal angles for solar panels [9], in this study both the angle and the mounting method were tested. The three PV mounting designs that were considered to provide the most insulation to a building's rooftop were flush, offset (control), and angled. The solar panel offset height became a key component for rooftop insulation as well as the performance of the actual solar panel. Experimental results were given to verify the thermal behavior of the heat loads from the different designs of the photovoltaic panel. From the results, the angled PV design needed 16Z more heat extraction than the offset and flush PV design needed 60% more heat extracted than the offset. In addition to the heat transfer analysis, thermal models were performed to incorporate main atmospheric conditions which were based on the effects of PV mounting structure.

  5. Condition Assessment Survey (CAS) Program. Deficiency standards and inspections methods manual: Volume 5, 0.05 Roofing

    SciTech Connect

    Not Available

    1993-05-01

    General information is presented for asset determinant factor/CAS repair codes/CAS cost factors; guide sheet tool & material listing; testing methods; inspection frequency; standard system design life tables; and system work breakdown structure. Deficiency standards and inspection methods are presented for built-up membrane; single- ply membrane; metal roofing systems; coated foam membrane; shingles; tiles; parapets; roof drainage system; roof specialties; and skylights.

  6. Predictive Service Life Tests for Roofing Membranes

    NASA Astrophysics Data System (ADS)

    Bailey, David M.; Cash, Carl G.; Davies, Arthur G.

    2002-09-01

    The average service life of roofing membranes used in low-slope applications on U.S. Army buildings is estimated to be considerably shorter than the industry-presumed 20-year design life, even when installers carefully adhere to the latest guide specifications. This problem is due in large part to market-driven product development cycles, which do not include time for long-term field testing. To reduce delivery costs, contractors may provide untested, interior membranes in place of ones proven satisfactory in long-term service. Federal procurement regulations require that roofing systems and components be selected according to desired properties and generic type, not brand name. The problem is that a material certified to have satisfactory properties at installation time will not necessarily retain those properties in service. The overall objective of this research is to develop a testing program that can be executed in a matter of weeks to adequately predict a membrane's long-term performance in service. This report details accelerated aging tests of 12 popular membrane materials in the laboratory, and describes outdoor experiment stations set up for long-term exposure tests of those same membranes. The laboratory results will later be correlated with the outdoor test results to develop performance models and predictive service life tests.

  7. Spatial environmental heterogeneity affects plant growth and thermal performance on a green roof.

    PubMed

    Buckland-Nicks, Michael; Heim, Amy; Lundholm, Jeremy

    2016-05-15

    Green roofs provide ecosystem services, including stormwater retention and reductions in heat transfer through the roof. Microclimates, as well as designed features of green roofs, such as substrate and vegetation, affect the magnitude of these services. Many green roofs are partially shaded by surrounding buildings, but the effects of this within-roof spatial environmental heterogeneity on thermal performance and other ecosystem services have not been examined. We quantified the effects of spatial heterogeneity in solar radiation, substrate depth and other variables affected by these drivers on vegetation and ecosystem services in an extensive green roof. Spatial heterogeneity in substrate depth and insolation were correlated with differential growth, survival and flowering in two focal plant species. These effects were likely driven by the resulting spatial heterogeneity in substrate temperature and moisture content. Thermal performance (indicated by heat flux and substrate temperature) was influenced by spatial heterogeneity in vegetation cover and substrate depth. Areas with less insolation were cooler in summer and had greater substrate moisture, leading to more favorable conditions for plant growth and survival. Spatial variation in substrate moisture (7%-26% volumetric moisture content) and temperature (21°C-36°C) during hot sunny conditions in summer could cause large differences in stormwater retention and heat flux within a single green roof. Shaded areas promote smaller heat fluxes through the roof, leading to energy savings, but lower evapotranspiration in these areas should reduce stormwater retention capacity. Spatial heterogeneity can thus result in trade-offs between different ecosystem services. The effects of these spatial heterogeneities are likely widespread in green roofs. Structures that provide shelter from sun and wind may be productively utilized to design higher functioning green roofs and increase biodiversity by providing habitat

  8. The Trade-off between Solar Reflectance and Above-Sheathing Ventilation for Metal Roofs on Residential and Commercial Buildings

    SciTech Connect

    Desjarlais, Andre Omer; Kriner, Scott; Miller, William A

    2013-01-01

    An alternative to white and cool-color roofs that meets prescriptive requirements for steep-slope (residential and non-residential) and low-slope (non-residential) roofing has been documented. Roofs fitted with an inclined air space above the sheathing (herein termed above-sheathing ventilation, or ASV), performed as well as if not better than high-reflectance, high-emittance roofs fastened directly to the deck. Field measurements demonstrated the benefit of roofs designed with ASV. A computer tool was benchmarked against the field data. Testing and benchmarks were conducted at roofs inclined at 18.34 ; the roof span from soffit to ridge was 18.7 ft (5.7 m). The tool was then exercised to compute the solar reflectance needed by a roof equipped with ASV to exhibit the same annual cooling load as that for a direct-to-deck cool-color roof. A painted metal roof with an air space height of 0.75 in. (0.019 m) and spanning 18.7 ft (5.7 m) up the roof incline of 18.34 needed only a 0.10 solar reflectance to exhibit the same annual cooling load as a direct-to-deck cool-color metal roof (solar reflectance of 0.25). This held for all eight ASHRAE climate zones complying with ASHRAE 90.1 (2007a). A dark heat-absorbing roof fitted with 1.5 in. (0.038 m) air space spanning 18.7 ft (5.7 m) and inclined at 18.34 was shown to have a seasonal cooling load equivalent to that of a conventional direct-to-deck cool-color metal roof. Computations for retrofit application based on ASHRAE 90.1 (1980) showed that ASV air spaces of either 0.75 or 1.5 in. (0.019 and 0.038 m) would permit black roofs to have annual cooling loads equivalent to the direct-to-deck cool roof. Results are encouraging, and a parametric study of roof slope and ASV aspect ratio is needed for developing guidelines applicable to all steep- and low-slope roof applications.

  9. Performance Evaluation of Advanced Retrofit Roof Technologies Using Field-Test Data Phase Three Final Report, Volume 1

    SciTech Connect

    Biswas, Kaushik; Childs, Phillip W; Atchley, Jerald Allen

    2014-05-01

    This article presents various metal roof configurations that were tested at Oak Ridge National Laboratory in Tennessee, U.S.A. between 2009 and 2013, and describes their potential for reducing the attic-generated space conditioning loads. These roofs contained different combinations of phase change material, rigid insulation, low emittance surface and above-sheathing ventilation, with standing-seam metal panels on top. These roofs were designed to be installed on existing roofs decks, or on top of asphalt shingles for retrofit construction. All the tested roofs showed the potential for substantial energy savings compared to an asphalt shingle roof, which was used as a control for comparison. The roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. The attics were built on top of a conditioned room. All attics were vented at the soffit and ridge. The test roofs and attics were instrumented with an array of thermocouples. Heat flux transducers were installed in the roof deck and attic floor (ceiling) to measure the heat flows through the roof and between the attic and conditioned space below. Temperature and heat flux data were collected during the heating, cooling and swing seasons over a 3 year period. Data from previous years of testing have been published. Here, data from the latest roof configurations being tested in year 3 of the project are presented. All test roofs were highly effective in reducing the heat flows through the roof and ceiling, and in reducing the diurnal attic temperature fluctuations.

  10. Seismic performance of pendulum and translational roof-garden TMDs

    NASA Astrophysics Data System (ADS)

    Matta, Emiliano; De Stefano, Alessandro

    2009-04-01

    In a previous paper, the authors already introduced the concept of the roof-garden TMD, an innovative passive vibration absorber for building structures, meant to combine the dynamic response mitigation capabilities of traditional tuned mass dampers (TMDs) with the environmental advantages of traditional roof gardens. In order to limit the mistuning effect and control loss due to the intrinsic variability of its mass, a roof-garden TMD of the rolling-pendulum type, advantageously characterized by a mass-independent natural period although unfortunately inherently non-linear, was then proposed and its performance assessed for increasing values of mass uncertainty and excitation levels. In the present study, the rolling-pendulum type is compared with the well-known translational configuration, the latter expectedly more prone to mistuning and yet insensitive to seismic intensity because of its linear behaviour. The trade-off between the two schemes is first explored for the case of a single-degree-of-freedom (SDOF) structure under a variety of design scenarios and then demonstrated through simulations on a building structure recently completed in a seismic site in Central Italy and designed to host a roof-garden atop for architectural purposes.

  11. Retention performance of green roofs in representative climates worldwide

    NASA Astrophysics Data System (ADS)

    Viola, F.; Hellies, M.; Deidda, R.

    2017-10-01

    role of climatic conditions, namely annual rainfall, potential evapotranspiration and their seasonality cycles, we found that they drive green roofs retention performance, which are the maxima when rainfall and temperature are in phase. Finally, we provide design charts for a first approximation of possible hydrological benefits deriving from the implementation of intensive or extensive green roofs in different world areas. As an example, 25 big cities have been indicated as benchmark case studies.

  12. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure testing... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed...

  13. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  14. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2010-10-01 2010-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  15. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  16. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  17. A Fiber Bragg Grating-Based Monitoring System for Roof Safety Control in Underground Coal Mining

    PubMed Central

    Zhao, Yiming; Zhang, Nong; Si, Guangyao

    2016-01-01

    Monitoring of roof activity is a primary measure adopted in the prevention of roof collapse accidents and functions to optimize and support the design of roadways in underground coalmines. However, traditional monitoring measures, such as using mechanical extensometers or electronic gauges, either require arduous underground labor or cannot function properly in the harsh underground environment. Therefore, in this paper, in order to break through this technological barrier, a novel monitoring system for roof safety control in underground coal mining, using fiber Bragg grating (FBG) material as a perceived element and transmission medium, has been developed. Compared with traditional monitoring equipment, the developed, novel monitoring system has the advantages of providing accurate, reliable, and continuous online monitoring of roof activities in underground coal mining. This is expected to further enable the prevention of catastrophic roof collapse accidents. The system has been successfully implemented at a deep hazardous roadway in Zhuji Coal Mine, China. Monitoring results from the study site have demonstrated the advantages of FBG-based sensors over traditional monitoring approaches. The dynamic impacts of progressive face advance on roof displacement and stress have been accurately captured by the novel roadway roof activity and safety monitoring system, which provided essential references for roadway support and design of the mine. PMID:27775657

  18. Integration of active and passive cool roof system for attic temperature reduction

    NASA Astrophysics Data System (ADS)

    Yew, Ming Chian; Yew, Ming Kun; Saw, Lip Huat; Durairaj, Rajkumar

    2017-04-01

    The aim of this project is to study the capability of cool roof system in the reduction of heat transmission through metal roof into an attic. The cool roof system is designed in active and passive methods to reduce the thermal loads imposed to a building. Two main features are introduced to this cool roof system, which is thermal insulation coating (TIC) and moving air cavity (MAC) that served as active and passive manner, respectively. For MAC, two designs are introduced. Normal MAC is fabricated by six aluminium tubes whereby each aluminium tube is made up by sticking up of five aluminium cans. While improved MAC is also made by six aluminium tubes whereby each aluminium tube is custom made from steel rods and aluminium foils. MAC provides ventilation and heat reflection under the metal roof before the heat transfer into attic. It also coupled with three solar powered fans to increase heat flow inside the channel. The cool roof that incorporated TIC, MAC with solar powered fans and opened attic inlet showed a significant improvement with a reduction of up to 14 °C in the attic temperature compared to conventional roof system.

  19. A Fiber Bragg Grating-Based Monitoring System for Roof Safety Control in Underground Coal Mining.

    PubMed

    Zhao, Yiming; Zhang, Nong; Si, Guangyao

    2016-10-21

    Monitoring of roof activity is a primary measure adopted in the prevention of roof collapse accidents and functions to optimize and support the design of roadways in underground coalmines. However, traditional monitoring measures, such as using mechanical extensometers or electronic gauges, either require arduous underground labor or cannot function properly in the harsh underground environment. Therefore, in this paper, in order to break through this technological barrier, a novel monitoring system for roof safety control in underground coal mining, using fiber Bragg grating (FBG) material as a perceived element and transmission medium, has been developed. Compared with traditional monitoring equipment, the developed, novel monitoring system has the advantages of providing accurate, reliable, and continuous online monitoring of roof activities in underground coal mining. This is expected to further enable the prevention of catastrophic roof collapse accidents. The system has been successfully implemented at a deep hazardous roadway in Zhuji Coal Mine, China. Monitoring results from the study site have demonstrated the advantages of FBG-based sensors over traditional monitoring approaches. The dynamic impacts of progressive face advance on roof displacement and stress have been accurately captured by the novel roadway roof activity and safety monitoring system, which provided essential references for roadway support and design of the mine.

  20. Orbital dystopia due to orbital roof defect.

    PubMed

    Rha, Eun Young; Joo, Hong Sil; Byeon, Jun Hee

    2013-01-01

    We performed a retrospective review of patients who presented with delayed dystopia as a consequence of an orbital roof defect due to fractures and nontraumatic causes to search for a correlation between orbital roof defect size and surgical indications for the treatment thereof. Retrospective analyses were performed in 7 patients, all of whom presented with delayed dystopia due to orbital roof defects, between January 2001 and June 2011. The causes of orbital roof defects were displaced orbital roof fractures (5 cases), tumor (1 case), and congenital sphenoid dysplasia (1 case). All 7 patients had initially been treated conservatively and later presented with significant dystopia. The sizes of the defects were calculated on computed tomographic scans. Among the 7 patients, aspiration of cerebrospinal fluid, which caused ocular symptoms, in 1 patient with minimal displaced orbital roof and reconstruction with calvarial bone, titanium micromesh, or Medpor in 6 other patients were performed. The minimal size of the orbital roof in patients who underwent orbital roof reconstruction was 1.2 cm (defect height) x 1.0 cm (defect length), 0.94 cm(2). For all patients with orbital dystopia, displacement of the globe was corrected without any complications, regardless of whether the patient was evaluated grossly or by radiology. In this retrospective study, continuous monitoring of clinical signs and active surgical management should be considered for cases in which an orbital roof defect is detected, even if no definite symptoms are noted, to prevent delayed sequelae.

  1. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... floating roof shall be equipped with a closure device between the wall of the storage vessel and the floating roof edge and shall consist of one of the following devices: (i) A liquid-mounted seal. (ii) A... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Fixed roof with an internal...

  2. Thermal Infrared Inspection of Roof Insulation Using Unmanned Aerial Vehicles

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Jung, J.; Sohn, G.; Cohen, M.

    2015-08-01

    UAVs equipped with high-resolution thermal cameras provide an excellent investigative tool used for a multitude of building-specific applications, including roof insulation inspection. We have presented in this study a relative thermographic calibration algorithm and a superpixel Markov Random Field model to address problems in thermal infrared inspection of roof insulation using UAVs. The relative thermographic radiometric calibration algorithm is designed to address the autogain problem of the thermal camera. Results show the algorithm can enhance the contrast between warm and cool areas on the roof surface in thermal images, and produces more constant thermal signatures of different roof insulations or surfaces, which could facilitate both visual interpretation and computer-based thermal anomaly detection. An automatic thermal anomaly detection algorithm based on superpixel Markov Random Field is proposed, which is more computationally efficient than pixel based MRF, and can potentially improve the production throughput capacity and increase the detection accuracy for thermal anomaly detection. Experimental results show the effectiveness of the proposed method.

  3. A guidebook for insulated low-slope roof systems. IEA Annex 19, Low-slope roof systems: International Energy Agency Energy Conservation in Buildings and Community Systems Programme

    SciTech Connect

    Not Available

    1994-02-01

    Low-slope roof systems are common on commercial and industrial buildings and, to a lesser extent, on residential buildings. Although insulating materials have nearly always been a component of low-slope roofs, the amount of insulation used has increased in the past two decades because of escalation of heating and cooling costs and increased awareness of the need for energy conservation. As the amount of insulation has increased, the demand has intensified for design, installation, and maintenance information specifically for well-insulated roofs. Existing practices for design, installation, and maintenance of insulated roofs have evolved from experience. Typically, these practices feature compromises due to the different properties of materials making up a given roof system. Therefore, they should be examined from time to time to ensure that they are appropriate as new materials continue to enter the market and as the data base on existing systems expands. A primary purpose of this International Energy Agency (IEA) study is to assess current roofing insulation practices in the context of an accumulating data base on performance.

  4. 30 CFR 75.221 - Roof control plan information.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to be used in the roof, face and rib control system, including, if roof bolts are to be installed— (i... mining approaches within 150 feet of an outcrop. (12) A description of the roof and rib support necessary...

  5. 4 Living roofs in 3 locations: Does configuration affect runoff mitigation?

    NASA Astrophysics Data System (ADS)

    Fassman-Beck, Elizabeth; Voyde, Emily; Simcock, Robyn; Hong, Yit Sing

    2013-05-01

    Four extensive living roofs and three conventional (control) roofs in Auckland, New Zealand have been evaluated over periods of 8 months to over 2 yrs for stormwater runoff mitigation. Up to 56% cumulative retention was measured from living roofs with 50-150 mm depth substrates installed over synthetic drainage layers, and with >80% plant coverage. Variation in cumulative %-retention amongst sites is attributed to different durations of monitoring, rather than actual performance. At all sites, runoff rarely occurred at all from storms with less than 25 mm of precipitation, from the combined effects of substrates designed to maximize moisture storage and because >90% of individual events were less than 25 mm. Living roof runoff depth per event is predicted well by a 2nd order polynomial model (R2 = 0.81), again demonstrating that small storms are well managed. Peak flow per event from the living roofs was 62-90% less than a corresponding conventional roof's runoff. Seasonal retention performance decreased slightly in winter, but was nonetheless substantial, maintaining 66% retention at one site compared to 45-93% in spring-autumn at two sites. Peak flow mitigation did not vary seasonally. During a 4-month period of concurrent monitoring at all sites, varied substrate depth did not influence runoff depth (volume), %-retention, or %-peak flow mitigation compared to a control roof at the same site. The magnitude of peak flow was greater from garden shed-scale living roofs compared to the full-scale living roofs. Two design aspects that could be manipulated to increase peak flow mitigation include lengthening the flow path through the drainage layer to vertical gutters and use of flow-retarding drainage layer materials.

  6. Habitat connectivity and local conditions shape taxonomic and functional diversity of arthropods on green roofs.

    PubMed

    Braaker, Sonja; Obrist, Martin Karl; Ghazoul, Jaboury; Moretti, Marco

    2017-05-01

    by specific trait assemblages. The study also provides details on the environmental conditions that influence arthropod diversity and gives new perspectives on how the design of green roofs can be improved to increase their ecological value. Furthermore, the study highlights the importance of integrating green roofs in planning policies which aim to enhance urban habitat connectivity. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  7. Analysis of vkorc1 polymorphisms in Norway rats using the roof rat as outgroup

    PubMed Central

    2010-01-01

    Background Certain mutations in the vitamin K epoxide reductase subcomponent 1 gene (vkorc1) mediate rodent resistance to warfarin and other anticoagulants. Testing for resistance often involves analysis of the vkorc1. However, a genetic test for the roof rat (Rattus rattus) has yet to be developed. Moreover, an available roof rat vkorc1 sequence would enable species identification based on vkorc1 sequence and the evaluation of natural selection on particular vkorc1 polymorphisms in the Norway rat (R. norvegicus). Results We report the coding sequence, introns and 5' and 3' termini for the vkorc1 gene of roof rats (R. r. alexandrinus and R. r. frugivorus) from Uganda, Africa. Newly designed PCR primers now enable genetic testing of the roof rat and Norway rat. Only synonymous and noncoding polymorphisms were found in roof rats from Uganda. Both nominal subspecies of roof rats were indistinguishable from each other but were distinct from R. losea and R. flavipectus; however, the roof rat also shares at least three coding sequence polymorphisms with R. losea and R. flavipectus. Many of recently published vkorc1 synonymous and non-synonymous single nucleotide polymorphisms (SNPs) in Norway rats are likely SNPs from roof rats and/or other Rattus species. Tests applied to presumably genuine Norway rat vkorc1 SNPs are consistent with a role for selection in two populations carrying the derived Phe63Cys and Tyr139Cys mutations. Conclusion Geographic mapping of vkorc1 SNPs in roof rats should be facilitated by our report. Our assay should be applicable to most species of Rattus, which are intermediate in genetic distance from roof and Norway rats. Vkorc1-mediated resistance due to non-synonymous coding SNPs is not segregating in roof rats from Uganda. By using the roof rat sequence as a reference vkorc1, SNPs now can be assigned to the correct rat species with more confidence. Sampling designs and genotyping strategies employed so far have helped detect candidate mutations

  8. Analysis of vkorc1 polymorphisms in Norway rats using the roof rat as outgroup.

    PubMed

    Díaz, Juan C; Song, Ying; Moore, Anthony; Borchert, Jeff N; Kohn, Michael H

    2010-05-24

    Certain mutations in the vitamin K epoxide reductase subcomponent 1 gene (vkorc1) mediate rodent resistance to warfarin and other anticoagulants. Testing for resistance often involves analysis of the vkorc1. However, a genetic test for the roof rat (Rattus rattus) has yet to be developed. Moreover, an available roof rat vkorc1 sequence would enable species identification based on vkorc1 sequence and the evaluation of natural selection on particular vkorc1 polymorphisms in the Norway rat (R. norvegicus). We report the coding sequence, introns and 5' and 3' termini for the vkorc1 gene of roof rats (R. r. alexandrinus and R. r. frugivorus) from Uganda, Africa. Newly designed PCR primers now enable genetic testing of the roof rat and Norway rat. Only synonymous and noncoding polymorphisms were found in roof rats from Uganda. Both nominal subspecies of roof rats were indistinguishable from each other but were distinct from R. losea and R. flavipectus; however, the roof rat also shares at least three coding sequence polymorphisms with R. losea and R. flavipectus. Many of recently published vkorc1 synonymous and non-synonymous single nucleotide polymorphisms (SNPs) in Norway rats are likely SNPs from roof rats and/or other Rattus species. Tests applied to presumably genuine Norway rat vkorc1 SNPs are consistent with a role for selection in two populations carrying the derived Phe63Cys and Tyr139Cys mutations. Geographic mapping of vkorc1 SNPs in roof rats should be facilitated by our report. Our assay should be applicable to most species of Rattus, which are intermediate in genetic distance from roof and Norway rats. Vkorc1-mediated resistance due to non-synonymous coding SNPs is not segregating in roof rats from Uganda. By using the roof rat sequence as a reference vkorc1, SNPs now can be assigned to the correct rat species with more confidence. Sampling designs and genotyping strategies employed so far have helped detect candidate mutations underlying vkorc1-mediated

  9. Coal Mine Roof Rating (CMRR): A practical rock mass classification for coal mines. Information circular/1994

    SciTech Connect

    Molinda, G.M.; Mark, C.

    1994-01-01

    The Coal Mine Roof Rating (CMRR) was developed by the U.S. Bureau of Mines as an engineering tool to quantify descriptive geologic information for use in coal mine design and roof support selection. The CMRR system combines the results of many years of geologic ground control research with worldwide experience with rock mass classification systems. Like other classification systems, the CMRR begins with the premise that the structural competence of mine roof rock is determined primarily by the discontinuities that weaken the rock fabric. The CMRR makes four unique contributions: (1) it is specifically designed for bedded coal measure rocks, (2) it concentrates on the bolted interval and its ability to form a stable mine structure, (3) it is applicable to all U.S. coal seams, and (4) it provides a methodology for data collection. Using only simple field tests and observations, the CMRR can be calculated from roof falls, overcasts, and highwall exposures.

  10. Sloshing roof impact tests of a rectangular tank

    NASA Astrophysics Data System (ADS)

    Minowa, Chikahiro; Ogawa, Nobuyuki; Harada, Iki; Ma, David C.

    Some tanks have been damaged at the roofs due to sloshing impact caused by strong earthquakes. It is, therefore, necessary to consider the impact force in the aseismic design code for tank roofs. However, there are few studies on the earthquake responses of storage and process tank roofs. As a first step to investigate the effects of sloshing impact a series of the shaking table tests of a rectangular tank have been conducted at the National Research Institute for Earth Science and Disaster Prevention (NIED). The results of these shaking table tests are presented in the paper. The test tank is rectangular in shape having dimensions of 5 m x 3 m x 2 m (length x width x height). The tank was constructed of glass-fiber reinforced plastic panels. Every panel had a flange on four edges, and each panel was connected by bolts along the flange. The test tank was set on the NIED shaking table (15 m by 15 m). Two types of liquid were used, water and a viscous liquid (water mixed with polymeric powders). The roof impact pressures and other quantities were measured. During the tests using the 400 pi El-Centro excitation, the roof deformation sensor steel beam was damaged. The response of side walls with different rigidity were measured in the wall bulging tests. The measured vibrations within the panel plates were larger than those in the panel flanges. The viscous liquid of 100 cp had little influence on wall bulging responses. However, the viscous effects on sloshing responses were observed in the sloshing tests. Approximate analyses of rectangular tanks, considering the influence of static water pressure, are also presented in this paper.

  11. Sloshing roof impact tests of a rectangular tank

    SciTech Connect

    Minowa, C.; Ogawa, N.; Harada, I.; Ma, D.C.

    1994-06-01

    Some tanks have been damaged at the roofs due to sloshing impact caused by strong earthquakes. It is, therefore, necessary to consider the impact force in the aseismic design code for tank roofs. However, there are few studies on the earthquake responses of storage and process tank roofs. As a first step to investigate the effects of sloshing impact a series of the shaking table tests of a rectangular tank have been conducted at the National Research Institute for Earth Science and Disaster Prevention (NIED). The results of these shaking table tests are presented in the paper. The test tank is rectangular in shape having dimensions of 5 m {times} 3 m {times} 2 m length {times} width {times} height). The tank was constructed of glass-fiber reinforced plastic panels. Every panel had a flange on four edges, and each panel was connected by bolts along the flange. The test tank was set on the NIED shaking table (15 m by 15 m). Two types of liquid were used, water and a viscous liquid (water mixed with polymeric powders). The roof impact pressures and other quantities were measured. During the tests using the 400 pi El-Centro excitation, the roof deformation sensor steel beam was damaged. The response of side walls with different rigidity were measured in the wall bulging tests. The measured vibrations within the panel plates were larger than those in the panel flanges. The viscous liquid of 100 cp had little influence on wall bulging responses. However, the viscous effects on sloshing responses were observed in the sloshing tests. Approximate analyses of rectangular tanks, considering the influence of static water pressure, are also presented in this paper.

  12. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    Dinwoodie, T.L.

    1998-05-05

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the preformed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  13. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    Dinwoodie, Thomas L.

    1998-01-01

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the preformed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  14. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    Dinwoodie, Thomas L.

    2006-02-28

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the pre-formed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  15. Roofs--Their Problems and Solutions.

    ERIC Educational Resources Information Center

    Swentkofske, Carl J.

    Most roofs are meant to withstand the elements for a period of 20 years; to achieve this goal, however, school officials must believe in a dedicated maintenance program and sell it to their superiors and school boards. Establishment of a school district roof maintenance program is explained. Job qualifications and training methods for an inhouse…

  16. Roof management alternatives for aging launch infrastructure

    NASA Astrophysics Data System (ADS)

    Firman, Dennis

    This paper describes a Roof Management System approach to better cope with aging and deteriorating infrastructure support facilities at our national spaceports. It describes facility conditions at the two Air Force space launch complexes and highlights an innovative cradle-to-grave alternate approach for repair and maintenance of roofing assets.

  17. Roofs--Their Problems and Solutions.

    ERIC Educational Resources Information Center

    Swentkofske, Carl J.

    Most roofs are meant to withstand the elements for a period of 20 years; to achieve this goal, however, school officials must believe in a dedicated maintenance program and sell it to their superiors and school boards. Establishment of a school district roof maintenance program is explained. Job qualifications and training methods for an inhouse…

  18. Experimental polyurethane foam roof systems, part 2

    NASA Astrophysics Data System (ADS)

    Alumbaugh, R. L.; Keeton, J. R.; Humm, E. F.

    1983-01-01

    An experimental roofing installation is described in which polyurethane foam (PUF) was spray-applied directly to metal Butlerib-type metal decks, the roof divided into five approximately equal areas, and the PUF protected with five different elastomeric coating systems. Three of the coating systems were damaged by hailstones about a year after installation; these systems were recoated within 3 years of the initial installation. The current coatings include two of the original coating systems - a plural component silicone and a single component silicone - and those applied over the three systems damaged by hail - a single component silicone, an aluminum filled, hydrocarbon-extended catalyzed urethane, and a catalyzed urethane. The performance of these five PUF systems over a 7-year period is reported. The temperature distributions throughout the roof systems are described. The decay in the thermal conductivity of the PUF roof over a 5-year period is presented, and the energy savings realized by foaming the roof are presented.

  19. Aging of reflective roofs: soot deposition.

    PubMed

    Berdahl, Paul; Akbari, Hashem; Rose, Leanna S

    2002-04-20

    Solar-reflective roofs remain cooler than absorptive roofs and thus conserve electricity otherwise needed for air conditioning. A currently controversial aspect of solar-reflective cool roofing is the extent to which an initially high solar reflectance decreases with time. We present experimental data on the spectral absorption of deposits that accumulate on roofs, and we attribute most of the absorption to carbon soot originally produced by combustion. The deposits absorb more at short wavelengths (e.g., in the blue) than in the red and infrared, imparting a slightly yellow tinge to formerly white surfaces. The initial rate of reflectance reduction by soot accumulation is consistent with known emission rates that are due to combustion. The long-term reflectance change appears to be determined by the ability of the soot to adhere to the roof, resisting washout by rain.

  20. Performance of dryland and wetland plant species on extensive green roofs.

    PubMed

    MacIvor, J Scott; Ranalli, Melissa A; Lundholm, Jeremy T

    2011-04-01

    Green roofs are constructed ecosystems where plants perform valuable services, ameliorating the urban environment through roof temperature reductions and stormwater interception. Plant species differ in functional characteristics that alter ecosystem properties. Plant performance research on extensive green roofs has so far indicated that species adapted to dry conditions perform optimally. However, in moist, humid climates, species typical of wetter soils might have advantages over dryland species. In this study, survival, growth and the performance of thermal and stormwater capture functions of three pairs of dryland and wetland plant species were quantified using an extensive modular green roof system. Seedlings of all six species were germinated in a greenhouse and planted into green roof modules with 6 cm of growing medium. There were 34 treatments consisting of each species in monoculture and all combinations of wet- and dryland species in a randomized block design. Performance measures were survival, vegetation cover and roof surface temperature recorded for each module over two growing seasons, water loss (an estimate of evapotranspiration) in 2007, and albedo and water capture in 2008. Over two seasons, dryland plants performed better than wetland plants, and increasing the number of dryland species in mixtures tended to improve functioning, although there was no clear effect of species or habitat group diversity. All species had survival rates >75 % after the first winter; however, dryland species had much greater cover, an important indicator of green roof performance. Sibbaldiopsis tridentata was the top performing species in monoculture, and was included in the best treatments. Although dryland species outperformed wetland species, planting extensive green roofs with both groups decreased performance only slightly, while increasing diversity and possibly habitat value. This study provides further evidence that plant composition and diversity can

  1. Performance of dryland and wetland plant species on extensive green roofs

    PubMed Central

    MacIvor, J. Scott; Ranalli, Melissa A.; Lundholm, Jeremy T.

    2011-01-01

    Background and Aims Green roofs are constructed ecosystems where plants perform valuable services, ameliorating the urban environment through roof temperature reductions and stormwater interception. Plant species differ in functional characteristics that alter ecosystem properties. Plant performance research on extensive green roofs has so far indicated that species adapted to dry conditions perform optimally. However, in moist, humid climates, species typical of wetter soils might have advantages over dryland species. In this study, survival, growth and the performance of thermal and stormwater capture functions of three pairs of dryland and wetland plant species were quantified using an extensive modular green roof system. Methods Seedlings of all six species were germinated in a greenhouse and planted into green roof modules with 6 cm of growing medium. There were 34 treatments consisting of each species in monoculture and all combinations of wet- and dryland species in a randomized block design. Performance measures were survival, vegetation cover and roof surface temperature recorded for each module over two growing seasons, water loss (an estimate of evapotranspiration) in 2007, and albedo and water capture in 2008. Key Results Over two seasons, dryland plants performed better than wetland plants, and increasing the number of dryland species in mixtures tended to improve functioning, although there was no clear effect of species or habitat group diversity. All species had survival rates >75 % after the first winter; however, dryland species had much greater cover, an important indicator of green roof performance. Sibbaldiopsis tridentata was the top performing species in monoculture, and was included in the best treatments. Conclusions Although dryland species outperformed wetland species, planting extensive green roofs with both groups decreased performance only slightly, while increasing diversity and possibly habitat value. This study provides further

  2. Green roof impact on the hydrological cycle components

    NASA Astrophysics Data System (ADS)

    Lamera, Carlotta; Rulli, Maria Cristina; Becciu, Gianfranco; Rosso, Renzo

    2013-04-01

    In the last decades the importance of storm water management in urban areas has increased considerably, due to both urbanization extension and to a greater concern for environment pollution. Traditional storm water control practices, based on the "all to the sewer" attitude, rely on conveyance to route storm water runoff from urban impervious surfaces towards the nearby natural water bodies. In recent years, infiltration facilities are receiving an increasing attention, due to their particular efficiency in restoring a balance in hydrological cycle quite equal to quite pre-urbanization condition. In particular, such techniques are designed to capture, temporarily retain and infiltrate storm water, promote evapotranspiration and harvest water at the source, encouraging in general evaporation, evapotranspiration, groundwater recharge and the re-use of storm water. Green roofs are emerging as an increasingly popular Sustainable Urban Drainage Systems (SUDS) technique for urban storm water management. Indeed, they are able to operate hydrologic control over storm water runoff: they allow a significant reduction of peak flows and runoff volumes collected by drainage system, with a consequent reduction of flooding events and pollution masses discharges by CSO. Furthermore green roofs have a positive influence on the microclimate in urban areas by helping in lower urban air temperatures and mitigate the heat island effect. Last but not least, they have the advantage of improving the thermal insulation of buildings, with significant energy savings. A detailed analysis of the hydrological dynamics, connected both with the characteristics of the climatic context and with the green roof technical design, is essential in order to obtain a full characterization of the hydrologic behavior of a green roof system and its effects on the urban water cycle components. The purpose of this paper is to analysis the hydrological effects and urban benefits of the vegetation cover of a

  3. Unique Roll-Off Roof for Housing 1.3 m Telescope at Devasthal, Nainital

    NASA Astrophysics Data System (ADS)

    Bangia, Tarun

    2016-05-01

    Aryabhatta Research Institute of Observational Sciences (ARIES) had set up a 1.3 m telescope at Devasthal, Nainital, India in the year 2010. Country's largest roll-off roof was indigenously designed, fabricated and installed on top of a building (17 × 8 m) for housing 1.3 m telescope. Telescope was supplied by M/s DFM Engineering Inc., USA to ARIES and was installed in the building with unique roll-off roof to protect it from external environment. Roll-off roof was designed and fabricated considering various parameters and available manpower and resources at ARIES. This paper presents mechanical development work, simple but distinct design approach and innovative selection of materials to economically manufacture roll-off roof of large size (8 × 8 × 4 m) at hilly remote site of Devasthal situated in Central Himalayan region. All operations in the roof viz. opening of shutters and rolling of roof were motorized to facilitate observers during night observations.

  4. Unique Roll-Off Roof for Housing 1.3 m Telescope at Devasthal, Nainital

    NASA Astrophysics Data System (ADS)

    Bangia, Tarun

    2017-06-01

    Aryabhatta Research Institute of Observational Sciences (ARIES) had set up a 1.3 m telescope at Devasthal, Nainital, India in the year 2010. Country's largest roll-off roof was indigenously designed, fabricated and installed on top of a building (17 × 8 m) for housing 1.3 m telescope. Telescope was supplied by M/s DFM Engineering Inc., USA to ARIES and was installed in the building with unique roll-off roof to protect it from external environment. Roll-off roof was designed and fabricated considering various parameters and available manpower and resources at ARIES. This paper presents mechanical development work, simple but distinct design approach and innovative selection of materials to economically manufacture roll-off roof of large size (8 × 8 × 4 m) at hilly remote site of Devasthal situated in Central Himalayan region. All operations in the roof viz. opening of shutters and rolling of roof were motorized to facilitate observers during night observations.

  5. Green roof stormwater retention: effects of roof surface, slope, and media depth.

    PubMed

    VanWoert, Nicholaus D; Rowe, D Bradley; Andresen, Jeffrey A; Rugh, Clayton L; Fernandez, R Thomas; Xiao, Lan

    2005-01-01

    Urban areas generate considerably more stormwater runoff than natural areas of the same size due to a greater percentage of impervious surfaces that impede water infiltration. Roof surfaces account for a large portion of this impervious cover. Establishing vegetation on rooftops, known as green roofs, is one method of recovering lost green space that can aid in mitigating stormwater runoff. Two studies were performed using several roof platforms to quantify the effects of various treatments on stormwater retention. The first study used three different roof surface treatments to quantify differences in stormwater retention of a standard commercial roof with gravel ballast, an extensive green roof system without vegetation, and a typical extensive green roof with vegetation. Overall, mean percent rainfall retention ranged from 48.7% (gravel) to 82.8% (vegetated). The second study tested the influence of roof slope (2 and 6.5%) and green roof media depth (2.5, 4.0, and 6.0 cm) on stormwater retention. For all combined rain events, platforms at 2% slope with a 4-cm media depth had the greatest mean retention, 87%, although the difference from the other treatments was minimal. The combination of reduced slope and deeper media clearly reduced the total quantity of runoff. For both studies, vegetated green roof systems not only reduced the amount of stormwater runoff, they also extended its duration over a period of time beyond the actual rain event.

  6. Proven Alternatives for Aboveground Treatment of Arsenic in Groundwater

    EPA Pesticide Factsheets

    This issue paper, developed for EPA's Engineering Forum, identifies and summarizes experiences with proven aboveground treatment alternatives for arsenic in groundwater, and provides information on their relative effectiveness and cost.

  7. NORTH ELEVATION WITH GRADUATED MEASURING POLE. ABOVEGROUND PORTION IS ON ...

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

    NORTH ELEVATION WITH GRADUATED MEASURING POLE. ABOVE-GROUND PORTION IS ON THE LEFT. VIEW FACING SOUTH - U.S. Naval Base, Pearl Harbor, Ford Island 5-Inch Antiaircraft Battery, Battery Command Center, Ford Island, Pearl City, Honolulu County, HI

  8. OBLIQUE VIEW WITH ABOVEGROUND PORTION IN THE FOREGROUND. VIEW FACING ...

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

    OBLIQUE VIEW WITH ABOVE-GROUND PORTION IN THE FOREGROUND. VIEW FACING SOUTHWEST - U.S. Naval Base, Pearl Harbor, Ford Island 5-Inch Antiaircraft Battery, Battery Command Center, Ford Island, Pearl City, Honolulu County, HI

  9. Use of treated woods in roof assembly.

    PubMed

    Edlich, Richard F; Winters, Kathryne L; Long, William B; Gubler, K Dean; Britt, L D

    2005-01-01

    On February 12, 2002, the US Environmental Protection Agency (EPA) announced a voluntary decision by industry to move consumer use of treated lumber products away from a variety of pressure-treated wood that contains Arsenate (As) by December 31, 2003, in favor of new alternative wood preservatives. It is the purpose of this report to outline legislative efforts to ban the use of chromated copper arsenate (CCA)-treated wood for residential roofing in the State of Oregon. At the time that the legislation was introduced, it was coincidental that the National Roofing Contractors Association (NRCA) recommended that CCA-treated wood should not be used in residential roofing. A summary of the report is included in this review. Finally, we discuss some of the potentially harmful environmental hazards of wood preservatives on the environment. In addition to the toxicity of pressure-treated wood on our environment, we point out that wood as well as pressure-treated wood assemblies are highly flammable. Consequently, we recommend the use of residential roofing systems that have Class A fire protection for the homeowner. Because residential roof fires remain a life-threatening danger to residential homeowners in the United States, we describe a national fire prevention program for reducing residential roof fires by use of an Underwriters Laboratories Inc. (UL) and National Fire Protection Association Class A fire-rated roof system.

  10. A two-stage storage routing model for green roof runoff detention.

    PubMed

    Vesuviano, Gianni; Sonnenwald, Fred; Stovin, Virginia

    2014-01-01

    Green roofs have been adopted in urban drainage systems to control the total quantity and volumetric flow rate of runoff. Modern green roof designs are multi-layered, their main components being vegetation, substrate and, in almost all cases, a separate drainage layer. Most current hydrological models of green roofs combine the modelling of the separate layers into a single process; these models have limited predictive capability for roofs not sharing the same design. An adaptable, generic, two-stage model for a system consisting of a granular substrate over a hard plastic 'egg box'-style drainage layer and fibrous protection mat is presented. The substrate and drainage layer/protection mat are modelled separately by previously verified sub-models. Controlled storm events are applied to a green roof system in a rainfall simulator. The time-series modelled runoff is compared to the monitored runoff for each storm event. The modelled runoff profiles are accurate (mean Rt(2) = 0.971), but further characterization of the substrate component is required for the model to be generically applicable to other roof configurations with different substrate.

  11. Modeling the effects of reflective roofing

    SciTech Connect

    Gartland, L.M.; Konopacki, S.J.; Akbari, H.

    1996-08-01

    Roofing materials which are highly reflective to sunlight are currently being developed. Reflective roofing is an effective summertime energy saver in warm and sunny climates. It has been demonstrated to save up to 40% of the energy needed to cool a building during the summer months. Buildings without air conditioning can reduce their indoor temperatures and improve occupant comfort during the summer if highly reflective roofing materials are used. But there are questions about the tradeoff between summer energy savings and extra wintertime energy use due to reduced heat collection by the roof. These questions are being answered by simulating buildings in various climates using the DOE-2 program (version 2.1E). Unfortunately, DOE-2 does not accurately model radiative, convective and conductive processes in the roof-attic. Radiative heat transfer from the underside of a reflective roof is much smaller than that of a roof which absorbs heat from sunlight, and must be accounted for in the building energy model. Convection correlations for the attic and the roof surface must be fine tuned. An equation to model the insulation`s conductivity dependence on temperature must also be added. A function was written to incorporate the attic heat transfer processes into the DOE-2 building energy simulation. This function adds radiative, convective and conductive equations to the energy balance of the roof. Results of the enhanced DOE-2 model were compared to measured data collected from a school bungalow in a Sacramento Municipal Utility District monitoring project, with particular attention paid to the year-round energy effects.

  12. Timber volume and aboveground live tree biomass estimations for landscape analyses in the Pacific Northwest

    Treesearch

    Xiaoping Zhou; Miles A. Hemstrom

    2010-01-01

    Timber availability, aboveground tree biomass, and changes in aboveground carbon pools are important consequences of landscape management. There are several models available for calculating tree volume and aboveground tree biomass pools. This paper documents species-specific regional equations for tree volume and aboveground live tree biomass estimation that might be...

  13. Aboveground and belowground competition between willow Salix caprea its understory

    NASA Astrophysics Data System (ADS)

    Mudrák, Ondřej; Hermová, Markéta; Frouz, Jan

    2016-04-01

    The effects of aboveground and belowground competition with the willow S. caprea on its understory plant community were studied in unreclaimed post-mining sites. Belowground competition was evaluated by comparing (i) frames inserted into the soil that excluded woody roots (frame treatment), (ii) frames that initially excluded woody root growth but then allowed regrowth of the roots (open-frame treatment), and (iii) undisturbed soil (no-frame treatment). These treatments were combined with S. caprea thinning to assess the effect of aboveground competition. Three years after the start of the experiment, aboveground competition from S. caprea (as modified by thinning of the S. caprea canopy) had not affected understory biomass or species number but had affected species composition. In contrast, belowground competition significantly affected both the aboveground and belowground biomass of the understory. The aboveground biomass of the understory was greater in the frame treatment (which excluded woody roots) than in the other two treatments. The belowground biomass of the understory was greater in the frame than in the open-frame treatment. Unlike aboveground competition (light availability), belowground competition did not affect understory species composition. Our results suggest that S. caprea is an important component during plant succession on post-mining sites because it considerably modifies its understory plant community. Belowground competition is a major reason for the low cover and biomass of the herbaceous understory in S. caprea stands on post-mining sites.

  14. 30 CFR 75.221 - Roof control plan information.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Roof control plan information. 75.221 Section... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.221 Roof control plan information. (a) The following information shall be included in each roof control plan: (1) The name...

  15. 30 CFR 75.220 - Roof control plan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Roof control plan. 75.220 Section 75.220... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.220 Roof control plan. (a)(1) Each mine operator shall develop and follow a roof control plan, approved by the District Manager, that is...

  16. 30 CFR 75.213 - Roof support removal.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Roof support removal. 75.213 Section 75.213... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.213 Roof support removal. (a)(1) All persons who perform the work of removing permanent roof supports shall be supervised by a...

  17. 30 CFR 75.220 - Roof control plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Roof control plan. 75.220 Section 75.220... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.220 Roof control plan. (a)(1) Each mine operator shall develop and follow a roof control plan, approved by the District Manager, that is...

  18. 30 CFR 75.220 - Roof control plan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Roof control plan. 75.220 Section 75.220... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.220 Roof control plan. (a)(1) Each mine operator shall develop and follow a roof control plan, approved by the District Manager, that is...

  19. 30 CFR 75.206 - Conventional roof support.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Conventional roof support. 75.206 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.206 Conventional roof support. (a) Except in anthracite mines using non-mechanized mining systems, when conventional roof...

  20. 30 CFR 75.206 - Conventional roof support.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Conventional roof support. 75.206 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.206 Conventional roof support. (a) Except in anthracite mines using non-mechanized mining systems, when conventional roof...

  1. Multifunctionality is affected by interactions between green roof plant species, substrate depth, and substrate type.

    PubMed

    Dusza, Yann; Barot, Sébastien; Kraepiel, Yvan; Lata, Jean-Christophe; Abbadie, Luc; Raynaud, Xavier

    2017-04-01

    Green roofs provide ecosystem services through evapotranspiration and nutrient cycling that depend, among others, on plant species, substrate type, and substrate depth. However, no study has assessed thoroughly how interactions between these factors alter ecosystem functions and multifunctionality of green roofs. We simulated some green roof conditions in a pot experiment. We planted 20 plant species from 10 genera and five families (Asteraceae, Caryophyllaceae, Crassulaceae, Fabaceae, and Poaceae) on two substrate types (natural vs. artificial) and two substrate depths (10 cm vs. 30 cm). As indicators of major ecosystem functions, we measured aboveground and belowground biomasses, foliar nitrogen and carbon content, foliar transpiration, substrate water retention, and dissolved organic carbon and nitrates in leachates. Interactions between substrate type and depth strongly affected ecosystem functions. Biomass production was increased in the artificial substrate and deeper substrates, as was water retention in most cases. In contrast, dissolved organic carbon leaching was higher in the artificial substrates. Except for the Fabaceae species, nitrate leaching was reduced in deep, natural soils. The highest transpiration rates were associated with natural soils. All functions were modulated by plant families or species. Plant effects differed according to the observed function and the type and depth of the substrate. Fabaceae species grown on natural soils had the most noticeable patterns, allowing high biomass production and high water retention but also high nitrate leaching from deep pots. No single combination of factors enhanced simultaneously all studied ecosystem functions, highlighting that soil-plant interactions induce trade-offs between ecosystem functions. Substrate type and depth interactions are major drivers for green roof multifunctionality.

  2. Innovative Ballasted Flat Roof Solar PV Racking System

    SciTech Connect

    Peek, Richard T.

    2014-12-15

    The objective of this project was to reduce the cost of racking for PV solar on flat commercial rooftops. Cost reductions would come from both labor savings and material savings related to the installation process. The rack would need to accommodate the majority of modules available on the market. Cascade Engineering has a long history of converting traditional metal type applications over to plastic. Injection molding of plastics have numerous advantages including selection of resin for the application, placing the material exactly where it is needed, designing in features that will speed up the installation process, and weight reduction of the array. A plastic rack would need to meet the requirements of UL2703, Mounting systems, mounting devices, clamping/retention devices, and ground lugs for use with flat-plate photovoltaic modules and panels. Comparing original data to the end of project racking design, racking material costs were reduced 50% and labor costs reduced 64%. The racking product accommodates all 60 and 72 cell panels on the market, meets UL2703 requirements, contributes only 1.3 pounds per square foot of weight to the array, requires little ballast to secure the array, automatically grounds the module when the module is secured, stacks/nests well for shipping/fewer lifts to the roof, provides integrated wire routing, allows water to drain on the roof, and accommodates various seismic roof connections. Project goals were achieved as noted in the original funding application.

  3. Metal and nutrient dynamics on an aged intensive green roof.

    PubMed

    Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

    2014-01-01

    Runoff and rainfall quality was compared between an aged intensive green roof and an adjacent conventional roof surface. Nutrient concentrations in the runoff were generally below Environmental Quality Standard (EQS) values and the green roof exhibited NO3(-) retention. Cu, Pb and Zn concentrations were in excess of EQS values for the protection of surface water. Green roof runoff was also significantly higher in Fe and Pb than on the bare roof and in rainfall. Input-output fluxes revealed the green roof to be a potential source of Pb. High concentrations of Pb within the green roof soil and bare roof dusts provide a potential source of Pb in runoff. The origin of the Pb is likely from historic urban atmospheric deposition. Aged green roofs may therefore act as a source of legacy metal pollution. This needs to be considered when constructing green roofs with the aim of improving pollution remediation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Performance Evaluation of Advanced Retrofit Roof Technologies Using Field-Test Data Phase Three Final Report, Volume 2

    SciTech Connect

    Biswas, Kaushik; Childs, Phillip W.; Atchley, Jerald Allen

    2015-01-01

    This article presents some miscellaneous data from two low-slope and two steep-slope experimental roofs. The low-slope roofs were designed to compare the performance of various roof coatings exposed to natural weatherization. The steep-slope roofs contained different combinations of phase change material, rigid insulation, low emittance surface and above-sheathing ventilation, with standing-seam metal panels on top. The steep-slope roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. This article describes phase three (3) of a study that began in 2009 to evaluate the energy benefits of a sustainable re-roofing technology utilizing standing-seam metal roofing panels combined with energy efficient features like above-sheathing-ventilation (ASV), phase change material (PCM) and rigid insulation board. The data from phases 1 and 2 have been previously published and reported [Kosny et al., 2011; Biswas et al., 2011; Biswas and Childs, 2012; Kosny et al., 2012]. Based on previous data analyses and discussions within the research group, additional test roofs were installed in May 2012, to test new configurations and further investigate different components of the dynamic insulation systems. Some experimental data from phase 3 testing from May 2012 to December 2013 and some EnergyPlus modeling results have been reported in volumes 1 and 3, respectively, of the final report [Biswas et al., 2014; Biswas and Bhandari, 2014].

  5. Cool Roofs Through Time and Space

    ScienceCinema

    Levinson, Ronnen

    2016-07-12

    Ronnen Levinson, from the Lab's Heat Island Group, presents his research on cool roofs and introduces the California Cities Albedo Map at our '8 Big Ideas' Science at the Theater event on October 8th, 2014, in Oakland, California

  6. MC Contracting, Paint, & Roofing, LLC Information Sheet

    EPA Pesticide Factsheets

    MC Contracting, Paint, & Roofing, LLC, d/b/a M.C. Painting & Contractor and M.C. Painting Group (the Company) is located in Philadelphia, Pennsylvania. The settlement involves renovation activities conducted at property constructed prior to 1978.

  7. Cool Roofs Through Time and Space

    SciTech Connect

    Levinson, Ronnen

    2014-10-17

    Ronnen Levinson, from the Lab's Heat Island Group, presents his research on cool roofs and introduces the California Cities Albedo Map at our '8 Big Ideas' Science at the Theater event on October 8th, 2014, in Oakland, California

  8. Legislative and regulatory update of aboveground storage tank requirements

    SciTech Connect

    Howard, J.L. Jr.

    1995-12-31

    Today, a patchwork of federal and state requirements regulate the three general categories of aboveground storage tanks: petroleum tanks (which comprise about 90% of all ASTs in use), hazardous substances tanks, and hazardous waste tanks. Various federal regulatory programs address ASTs, including the Clean Water Act, the Clean Air Act, and the Resource Conservation and Recovery Act (RCRA). At the state or local level, regulations and building codes have incorporated industry guidelines for designing, building, and testing tanks for fire prevention and safety purposes. With respect to environmental protection requirements, only the hazardous waste tanks are subject to a comprehensive federal regulatory program, under RCRA, and the states have adopted these federal regulations or promulgated their own. Some states have enacted comprehensive tank programs governing petroleum, and a few have addressed hazardous substances. The prospects for comprehensive legislation or regulation for petroleum ASTs in 1995, however, are dim. Federal legislation has been introduced, the Environmental Protection Agency (EPA) is studying ASTs, and most states are waiting for Congress and EPA to act. The paper briefly summarizes the applicable federal and state regulations and then discusses federal legislative and regulatory developments.

  9. Effects of substrate properties on the hydraulic and thermal behavior of a green roof

    NASA Astrophysics Data System (ADS)

    Sandoval, V. P.; Suarez, F. I.; Victorero, F.; Bonilla, C.; Gironas, J. A.; Vera, S.; Bustamante, W.; Rojas, V.; Pasten, P.

    2014-12-01

    Green roofs are a sustainable urban development solution that incorporates a growing media (also known as substrate) and vegetation into infrastructures to reach additional benefits such as the reduction of: rooftop runoff peak flows, roof surface temperatures, energy utilized for cooling/heating buildings, and the heat island effect. The substrate is a key component of the green roof that allows achieving these benefits. It is an artificial soil that has an improved behavior compared to natural soils, facilitating vegetation growth, water storage and typically with smaller densities to reduce the loads over the structures. Therefore, it is important to study the effects of substrate properties on green roof performance. The objective of this study is to investigate the physical properties of four substrates designed to improve the behavior of a green roof, and to study their impact on the efficiency of a green roof. The substrates that were investigated are: organic soil; crushed bricks; a mixture of mineral soil with perlite; and a mixture of crushed bricks and organic soil. The thermal properties (thermal conductivity, volumetric heat capacity and thermal diffusivity) were measured using a dual needle probe (Decagon Devices, Inc.) at different saturation levels, and the hydraulic properties were measured with a constant head permeameter (hydraulic conductivity) and a pressure plate extractor (water retention curve). This characterization, combined with numerical models, allows understanding the effect of these properties on the hydraulic and thermal behavior of a green roof. Results show that substrates composed by crushed bricks improve the thermal insulation of infrastructures and at the same time, retain more water in their pores. Simulation results also show that the hydraulic and thermal behavior of a green roof strongly depends on the moisture content prior to a rainstorm.

  10. Laboratory measurements of the drying rates of low-slope roofing systems

    SciTech Connect

    Desjarlais, A.O.; Kyle, D.M.; Childs, P.W.; Christian, J.E.

    1994-05-01

    The service life of a roofing system typically ends when excessive amounts of water have entered the system. Roofing professionals determine whether the existing failed roofing system can be repaired or salvaged by recovering. A key element in this decision is whether the accumulated water will be able to leave the roofing system in a time frame that will prevent irreparable structural damage. There are several combined heat and mass transfer models that can be used to predict drying times for low-slope roofing systems. Very little experimental data exists that can be used to validate the performance of these models. To satisfy these needs, a series of laboratory experiments has been performed. Five test panels, comprised of a plywood deck, four types of roofing insulation, and a single ply membrane were installed in a climate simulator. The test panels were outfitted with temperature sensors and heat flux transducers, and were mounted on load cells. Water was added to the test panels and they were subjected to external diurnal cycles representative of summer and winter conditions for a southern US continental climate. The load cells supplied continuous records of the weights of the test panels; these data were used to compute the drying rates of the test panels. When these experiments were completed, the test panels were ``recovered`` with different thicknesses of insulation and the environmental conditions were reapplied to the test panels. This paper reports on the design and performance of these experiments. The data compiled during these tests supply insight into the effects of meteorological conditions, insulation R-value, insulation water vapor permeance, and roof recover on the rate that water will be removed from low-slope roofing systems.

  11. Evaluation of green roof as green technology for urban stormwater quantity and quality controls

    NASA Astrophysics Data System (ADS)

    Kok, K. H.; Sidek, L. M.; Abidin, M. R. Z.; Basri, H.; Muda, Z. C.; Beddu, S.

    2013-06-01

    Promoting green design, construction, reconstruction and operation of buildings has never been more critical than now due to the ever increasing greenhouse gas emissions and rapid urbanizations that are fuelling climate change more quickly. Driven by environmental needs, Green Building Index (GBI) was founded in Malaysia to drive initiative to lead the property industry towards becoming more environment-friendly. Green roof system is one of the assessment criteria of this rating system which is under category of sustainable site planning and management. An extensive green roof was constructed in Humid Tropics Center (HTC) Kuala Lumpur as one of the components for Stormwater Management Ecohydrology (SME) in order to obtain scientific data of the system. This paper evaluates the performance of extensive green roof at Humid Tropics Center with respect to urban heat island mitigation and stormwater quantity and quality controls. Findings indicate that there was a reduction of around 1.5°C for indoor temperature of the building after installation of green roof. Simulations showed that the peak discharge was reduced up to 24% relative to impervious brown roof. The results show an increment of pH and high concentration of phosphate for the runoff generated from the green roof and the runoff water quality ranged between class I and II under INWQS.

  12. Personal computer program and spreadsheet for calculating the coal mine roof rating (CMRR). Information circular/1994

    SciTech Connect

    Riefenberg, J.; Wuest, W.J.

    1994-01-01

    A family of personal computer programs that calculate the Coal Mine Roof Rating (CMRR) have been developed by the U.S. Bureau of Mines. The CMRR, rock mass classification system, was recently developed by Bureau researchers to provide a link between the qualitative geologists' description of coal mine roof and the quantitive mine engineers' needs for mine design, roof support selection, and hazard detection. The program CMRR, is a user-friendly, interactive program into which raw field data are input, and a CMRR is calculated and output along with two graphic displays. The first graphic display is a plan view map with the roof ratings displayed on a color-coded scale, and the second display shows a stratigraphic section of the bolted roof interval and its resultant roof rating. In addition, a Lotus 1-2-3 worksheet, BOM-CMRR.WK3, has been developed for easy storage of field data. The worksheet also includes macros developed for calculation and storage of the CMRR. Production of summary reports for analysis of site-specific information are readily generated using Lotus. These programs help to facilitate the engineer in utilizing the CMRR in ground control studies.

  13. Analysis of DOE s Roof Savings Calculator with Comparison to other Simulation Engines

    SciTech Connect

    New, Joshua Ryan; Huang, Yu; Levinson, Ronnen; Mellot, Joe; Sanyal, Jibonananda; Childs, Kenneth W

    2014-01-01

    A web-based Roof Savings Calculator (RSC) has been deployed for the Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. This tool employs the latest web technologies and usability design to provide an easy input interface to an annual simulation of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim. Building defaults were assigned based on national averages and can provide estimated annual energy and cost savings after the user selects nothing more than building location. In addition to cool reflective roofs, the RSC tool can simulate multiple roof and attic configurations including different roof slopes, above sheathing ventilation, radiant barriers, low-emittance surfaces, HVAC duct location, duct leakage rates, multiple layers of building materials, ceiling and deck insulation levels, and other parameters. A base case and energy-efficient alternative can be compared side-by-side to generate an energy/cost savings estimate between two buildings. The RSC tool was benchmarked against field data for demonstration homes in Ft. Irwin, CA. However, RSC gives different energy savings estimates than previous cool roof simulation tools so more thorough software and empirical validation proved necessary. This report consolidates much of the preliminary analysis for comparison of RSC s projected energy savings to that from other simulation engines.

  14. Liquid storage tank with floating roof structure

    SciTech Connect

    Vaughn, L.G.

    1993-07-27

    In a cylindrical wall storage tank for containing a liquid, said tank is described having a floor, a floatable roof supportable by said contained liquid, said roof including a peripheral seal for engaging the cylindrical wall to maintain a fluid-tight sliding seal therewith, and support means associated with said roof including, the improvement in said tank of, at least one cylindrical guide sleeve extending downwardly from said floatable roof; a shoe depending laterally from said at least one cylindrical guide sleeve's lower end for engaging the tank floor when the level of contained liquid is insufficient to support said floatable roof, said shoe having means forming a passage there through to register a support column and, an elongated support column removably positioned in said at least one cylindrical guide sleeve, of being sufficient length to extend downward beyond the shoe to engage the tank floor, whereby to sustain the floatable roof a predetermined distance above said floor after the contained liquid has drained from the tank.

  15. Study of water infiltration in a lightweight green roof substrate

    NASA Astrophysics Data System (ADS)

    Tomankova, Klara; Holeckova, Martina; Jelinkova, Vladimira; Snehota, Michal

    2015-04-01

    Green roofs have a positive impact on the environment (e.g. improving microclimate and air quality in cities, reducing solar absorbance and storm water). A laboratory infiltration experiment was conducted on the narrow flume serving as 2D vertical model of a green roof. The lightweight Optigreen substrate Type M was used (depth of 20 cm). The front wall of the flume was transparent and inspected by digital camera. The experiment was designed to measure pressure head, volumetric water content and calculate water retention in the substrate. Experiment comprised three artificial rainfall intensities with different values of initial water content of the substrate. The experimental results confirmed that green roofs have the ability to retain rainwater and thus have a beneficial effect on reducing runoff. In the experiment with the artificial 10 minutes rainfall event (total precipitation of 29 mm), the air dry substrate retained 95.9 % of precipitation. On the other hand for moist initial condition 4.2 % of precipitations amount was captured in the substrate. Additionally, the analysis of images taken during the experiment confirmed preferential flow and uneven advancement of the wetting front. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.

  16. 40 CFR 264.1201 - Design and operating standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) Earth-covered magazines. Earth-covered magazines must be: (i) Constructed of waterproofed, reinforced... of any explosion. (2) Above-ground magazines. Above-ground magazines must be located and designed...

  17. 40 CFR 264.1201 - Design and operating standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Earth-covered magazines. Earth-covered magazines must be: (i) Constructed of waterproofed, reinforced... of any explosion. (2) Above-ground magazines. Above-ground magazines must be located and designed...

  18. 40 CFR 264.1201 - Design and operating standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Earth-covered magazines. Earth-covered magazines must be: (i) Constructed of waterproofed, reinforced... of any explosion. (2) Above-ground magazines. Above-ground magazines must be located and designed...

  19. MODIS Based Estimation of Forest Aboveground Biomass in China.

    PubMed

    Yin, Guodong; Zhang, Yuan; Sun, Yan; Wang, Tao; Zeng, Zhenzhong; Piao, Shilong

    2015-01-01

    Accurate estimation of forest biomass C stock is essential to understand carbon cycles. However, current estimates of Chinese forest biomass are mostly based on inventory-based timber volumes and empirical conversion factors at the provincial scale, which could introduce large uncertainties in forest biomass estimation. Here we provide a data-driven estimate of Chinese forest aboveground biomass from 2001 to 2013 at a spatial resolution of 1 km by integrating a recently reviewed plot-level ground-measured forest aboveground biomass database with geospatial information from 1-km Moderate-Resolution Imaging Spectroradiometer (MODIS) dataset in a machine learning algorithm (the model tree ensemble, MTE). We show that Chinese forest aboveground biomass is 8.56 Pg C, which is mainly contributed by evergreen needle-leaf forests and deciduous broadleaf forests. The mean forest aboveground biomass density is 56.1 Mg C ha-1, with high values observed in temperate humid regions. The responses of forest aboveground biomass density to mean annual temperature are closely tied to water conditions; that is, negative responses dominate regions with mean annual precipitation less than 1300 mm y-1 and positive responses prevail in regions with mean annual precipitation higher than 2800 mm y-1. During the 2000s, the forests in China sequestered C by 61.9 Tg C y-1, and this C sink is mainly distributed in north China and may be attributed to warming climate, rising CO2 concentration, N deposition, and growth of young forests.

  20. MODIS Based Estimation of Forest Aboveground Biomass in China

    PubMed Central

    Sun, Yan; Wang, Tao; Zeng, Zhenzhong; Piao, Shilong

    2015-01-01

    Accurate estimation of forest biomass C stock is essential to understand carbon cycles. However, current estimates of Chinese forest biomass are mostly based on inventory-based timber volumes and empirical conversion factors at the provincial scale, which could introduce large uncertainties in forest biomass estimation. Here we provide a data-driven estimate of Chinese forest aboveground biomass from 2001 to 2013 at a spatial resolution of 1 km by integrating a recently reviewed plot-level ground-measured forest aboveground biomass database with geospatial information from 1-km Moderate-Resolution Imaging Spectroradiometer (MODIS) dataset in a machine learning algorithm (the model tree ensemble, MTE). We show that Chinese forest aboveground biomass is 8.56 Pg C, which is mainly contributed by evergreen needle-leaf forests and deciduous broadleaf forests. The mean forest aboveground biomass density is 56.1 Mg C ha−1, with high values observed in temperate humid regions. The responses of forest aboveground biomass density to mean annual temperature are closely tied to water conditions; that is, negative responses dominate regions with mean annual precipitation less than 1300 mm y−1 and positive responses prevail in regions with mean annual precipitation higher than 2800 mm y−1. During the 2000s, the forests in China sequestered C by 61.9 Tg C y−1, and this C sink is mainly distributed in north China and may be attributed to warming climate, rising CO2 concentration, N deposition, and growth of young forests. PMID:26115195

  1. Research on the compressive strength of a passenger vehicle roof

    NASA Astrophysics Data System (ADS)

    Zhao, Guanglei; Cao, Jianxiao; Liu, Tao; Yang, Na; Zhao, Hongguang

    2017-05-01

    To study the compressive strength of a passenger vehicle roof, this paper makes the simulation test on the static collapse of the passenger vehicle roof and analyzes the stress and deformation of the vehicle roof under pressure in accordance with the Roof Crush Resistance of Passenger Cars (GB26134-2010). It studies the optimization on the major stressed parts, pillar A, pillar B and the rail of roof, during the static collapse process of passenger vehicle roof. The result shows that the thickness of pillar A and the roof rail has significant influence on the compressive strength of the roof while that of pillar B has minor influence on the compressive strength of the roof.

  2. Green roof valuation: a probabilistic economic analysis of environmental benefits.

    PubMed

    Clark, Corrie; Adriaens, Peter; Talbot, F Brian

    2008-03-15

    Green (vegetated) roofs have gained global acceptance as a technologythat has the potential to help mitigate the multifaceted, complex environmental problems of urban centers. While policies that encourage green roofs exist atthe local and regional level, installation costs remain at a premium and deter investment in this technology. The objective of this paper is to quantitatively integrate the range of stormwater, energy, and air pollution benefits of green roofs into an economic model that captures the building-specific scale. Currently, green roofs are primarily valued on increased roof longevity, reduced stormwater runoff, and decreased building energy consumption. Proper valuation of these benefits can reduce the present value of a green roof if investors look beyond the upfront capital costs. Net present value (NPV) analysis comparing a conventional roof system to an extensive green roof system demonstrates that at the end of the green roof lifetime the NPV for the green roof is between 20.3 and 25.2% less than the NPV for the conventional roof over 40 years. The additional upfront investment is recovered at the time when a conventional roof would be replaced. Increasing evidence suggests that green roofs may play a significant role in urban air quality improvement For example, uptake of N0x is estimated to range from $1683 to $6383 per metric ton of NOx reduction. These benefits were included in this study, and results translate to an annual benefit of $895-3392 for a 2000 square meter vegetated roof. Improved air quality leads to a mean NPV for the green roof that is 24.5-40.2% less than the mean conventional roof NPV. Through innovative policies, the inclusion of air pollution mitigation and the reduction of municipal stormwater infrastructure costs in economic valuation of environmental benefits of green roofs can reduce the cost gap that currently hinders U.S. investment in green roof technology.

  3. Steering Soil Microbiomes to Suppress Aboveground Insect Pests.

    PubMed

    Pineda, Ana; Kaplan, Ian; Bezemer, T Martijn

    2017-09-01

    Soil-borne microbes affect aboveground herbivorous insects through a cascade of molecular and chemical changes in the plant, but knowledge of these microbe-plant-insect interactions is mostly limited to one or a few microbial strains. Yet, the soil microbial community comprises thousands of unique taxa interacting in complex networks, the so-called 'microbiome', which provides plants with multiple beneficial functions. There has been little exploration of the role and management of whole microbiomes in plant-insect interactions, calling for the integration of this complexity in aboveground-belowground research. Here, we propose holistic approaches to select soil microbiomes that can be used to protect plants from aboveground attackers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. The variable effects of soil nitrogen availability and insect herbivory on aboveground and belowground plant biomass in an old-field ecosystem.

    PubMed

    Blue, Jarrod D; Souza, Lara; Classen, Aimée T; Schweitzer, Jennifer A; Sanders, Nathan J

    2011-11-01

    Nutrient availability and herbivory can regulate primary production in ecosystems, but little is known about how, or whether, they may interact with one another. Here, we investigate how nitrogen availability and insect herbivory interact to alter aboveground and belowground plant community biomass in an old-field ecosystem. In 2004, we established 36 experimental plots in which we manipulated soil nitrogen (N) availability and insect abundance in a completely randomized plot design. In 2009, after 6 years of treatments, we measured aboveground biomass and assessed root production at peak growth. Overall, we found a significant effect of reduced soil N availability on aboveground biomass and belowground plant biomass production. Specifically, responses of aboveground and belowground community biomass to nutrients were driven by reductions in soil N, but not additions, indicating that soil N may not be limiting primary production in this ecosystem. Insects reduced the aboveground biomass of subdominant plant species and decreased coarse root production. We found no statistical interactions between N availability and insect herbivory for any response variable. Overall, the results of 6 years of nutrient manipulations and insect removals suggest strong bottom-up influences on total plant community productivity but more subtle effects of insect herbivores on aspects of aboveground and belowground production.

  5. Water quality and quantity investigation of green roofs in a dry climate.

    PubMed

    Beecham, S; Razzaghmanesh, M

    2015-03-01

    Low-energy pollutant removal strategies are now being sought for water sensitive urban design. This paper describes investigations into the water quality and quantity of sixteen, low-maintenance and unfertilized intensive and extensive green roof beds. The factors of Slope (1° and 25°), Depth (100 mm and 300 mm), Growing media (type A, type B and type C) and Species (P1, P2 and P3) were randomized according to a split-split plot design. This consisted of twelve vegetated green roof beds and four non-vegetated beds as controls. Stormwater runoff was collected from drainage points that were installed in each area. Samples of run-off were collected for five rainfall events and analysed for water retention capacity and the water quality parameters of NO₂, NO₃, NH₄, PO₄, pH, EC, TDS, Turbidity, Na, Ca, Mg and K. The results indicated significant differences in terms of stormwater water quality and quantity between the outflows of vegetated and non-vegetated systems. The water retention was between 51% and 96% and this range was attributed to the green roof configurations in the experiment. Comparing the quality of rainfall as inflow, and the quality of runoff from the systems showed that green roofs generally acted as a source of pollutants in this study. In the vegetated beds, the intensive green roofs performed better than the extensive beds with regard to outflow quality while in the non-vegetated beds, the extensive beds performed better than intensive systems. This highlights the importance of vegetation in improving water retention capacity as well as the role of vegetation in enhancing pollutant removal in green roof systems. In addition growing media with less organic matter had better water quality performance. Comparison of these results with national and international standards for water reuse confirmed that the green roof outflow was suitable for non-potable uses such as landscape irrigation and toilet flushing. Copyright © 2014 Elsevier Ltd. All

  6. The Development of a Roof Integrated Solar Hot Water System

    SciTech Connect

    Menicucci, David F.; Moss, Timothy A.; Palomino, G. Ernest

    2006-09-01

    The Salt River Project (SRP), in conjunction with Sandia National Laboratories (SNL) and Energy Laboratories, Inc. (ELI), collaborated to develop, test, and evaluate an advanced solar water-heating product for new homes. SRP and SNL collaborated under a Department of Energy Cooperative Research and Development Agreement (CRADA), with ELI as SRP's industry partner. The project has resulted in the design and development of the Roof Integrated Thermal Siphon (RITH) system, an innovative product that features complete roof integration, a storage tank in the back of the collector and below the roofline, easy installation by homebuilders, and a low installed cost. SRP's market research guided the design, and the laboratory tests conducted at SNL provided information used to refine the design of field test units and indicated that the RITH concept is viable. ELI provided design and construction expertise and is currently configured to manufacture the units. This final report for the project provides all of the pertinent and available materials connected to the project including market research studies, the design features and development of the system, and the testing and evaluation conducted at SNL and at a model home test site in Phoenix, Arizona.

  7. Fuel consumption impacts of auto roof racks

    DOE PAGES

    Chen, Yuche; Meier, Alan

    2016-03-23

    The after-market roof rack is one of the most common components attached to a vehicle for carrying over-sized items, such as bicycles and skis. It is important to understand these racks' fuel consumption impacts on both individual vehicles and the national fleet because they are widely used. We estimate the national fuel consumption impacts of roof racks using a bottom-up approach. Our model incorporates real-world data and vehicle stock information to enable assessing fuel consumption impacts for several categories of vehicles, rack configurations, and usage conditions. In addition, the model draws on two new data-gathering techniques, on-line forums and crowd-sourcing.more » The results show that nationwide, roof racks are responsible for 0.8‰ of light duty vehicle fuel consumption in 2015, corresponding to 100 million gallons of gasoline per year. Sensitivity analyses show that results are most sensitive to the fraction of vehicles with installed roof racks but carrying no equipment. Here, the aerodynamic efficiency of typical roof racks can be greatly improved and reduce individual vehicle fuel consumption; however, government policies to minimize extensive driving with empty racks--if successful--could save more fuel nationally.« less

  8. Fuel consumption impacts of auto roof racks

    SciTech Connect

    Chen, Yuche; Meier, Alan

    2016-03-23

    The after-market roof rack is one of the most common components attached to a vehicle for carrying over-sized items, such as bicycles and skis. It is important to understand these racks' fuel consumption impacts on both individual vehicles and the national fleet because they are widely used. We estimate the national fuel consumption impacts of roof racks using a bottom-up approach. Our model incorporates real-world data and vehicle stock information to enable assessing fuel consumption impacts for several categories of vehicles, rack configurations, and usage conditions. In addition, the model draws on two new data-gathering techniques, on-line forums and crowd-sourcing. The results show that nationwide, roof racks are responsible for 0.8‰ of light duty vehicle fuel consumption in 2015, corresponding to 100 million gallons of gasoline per year. Sensitivity analyses show that results are most sensitive to the fraction of vehicles with installed roof racks but carrying no equipment. Here, the aerodynamic efficiency of typical roof racks can be greatly improved and reduce individual vehicle fuel consumption; however, government policies to minimize extensive driving with empty racks--if successful--could save more fuel nationally.

  9. Fuel Consumption Impacts of Auto Roof Racks

    SciTech Connect

    Chen, Yuche; Meier, Alan

    2016-05-01

    The after-market roof rack is one of the most common components attached to a vehicle for carrying over-sized items, such as bicycles and skis. It is important to understand these racks' fuel consumption impacts on both individual vehicles and the national fleet because they are widely used. We estimate the national fuel consumption impacts of roof racks using a bottom-up approach. Our model incorporates real-world data and vehicle stock information to enable assessing fuel consumption impacts for several categories of vehicles, rack configurations, and usage conditions. In addition, the model draws on two new data-gathering techniques, on-line forums and crowd-sourcing. The results show that nationwide, roof racks are responsible for 0.8% of light duty vehicle fuel consumption in 2015, corresponding to 100 million gallons of gasoline per year. Sensitivity analyses show that results are most sensitive to the fraction of vehicles with installed roof racks but carrying no equipment. The aerodynamic efficiency of typical roof racks can be greatly improved and reduce individual vehicle fuel consumption; however, government policies to minimize extensive driving with empty racks--if successful--could save more fuel nationally.

  10. Green roof rainfall-runoff modelling: is the comparison between conceptual and physically based approaches relevant?

    NASA Astrophysics Data System (ADS)

    Versini, Pierre-Antoine; Tchiguirinskaia, Ioulia; Schertzer, Daniel

    2017-04-01

    Green roofs are commonly considered as efficient tools to mitigate urban runoff as they can store precipitation, and consequently provide retention and detention performances. Designed as a compromise between water holding capacity, weight and hydraulic conductivity, their substrate is usually an artificial media differentiating significantly from a traditional soil. In order to assess green roofs hydrological performances, many models have been developed. Classified into two categories (conceptual and physically based), they are usually applied to reproduce the discharge of a particular monitored green roof considered as homogeneous. Although the resulted simulations could be satisfactory, the question of robustness and consistency of the calibrated parameters is often not addressed. Here, a modeling framework has been developed to assess the efficiency and the robustness of both modelling approaches (conceptual and physically based) in reproducing green roof hydrological behaviour. SWMM and VS2DT models have been used for this purpose. This work also benefits from an experimental setup where several green roofs differentiated by their substrate thickness and vegetation cover are monitored. Based on the data collected for several rainfall events, it has been studied how the calibrated parameters are effectively linked to their physical properties and how they can vary from one green roof configuration to another. Although both models reproduce correctly the observed discharges in most of the cases, their calibrated parameters exhibit a high inconsistency. For a same green roof configuration, these parameters can vary significantly from one rainfall event to another, even if they are supposed to be linked to the green roof characteristics (roughness, residual moisture content for instance). They can also be different from one green roof configuration to another although the implemented substrate is the same. Finally, it appears very difficult to find any

  11. Mapping Aboveground Biomass in the Amazon Basin: Exploring Sensors, Scales, and Strategies for Optimal Data Linkage

    NASA Astrophysics Data System (ADS)

    Walker, W. S.; Baccini, A.

    2013-05-01

    Information on the distribution and density of carbon in tropical forests is critical to decision-making on a host of globally significant issues ranging from climate stabilization and biodiversity conservation to poverty reduction and human health. Encouraged by recent progress at both the international and jurisdictional levels on the design of incentive-based policy mechanisms to compensate tropical nations for maintaining their forests intact, governments throughout the tropics are moving with urgency to implement robust national and sub-national forest monitoring systems for operationally tracking and reporting on changes in forest cover and associated carbon stocks. Monitoring systems will be required to produce results that are accurate, consistent, complete, transparent, and comparable at sub-national to pantropical scales, and satellite-based remote sensing supported by field observations is widely-accepted as the most objective and cost-effective solution. The effectiveness of any system for large-area forest monitoring will necessarily depend on the capacity of current and near-future Earth observation satellites to provide information that meets the requirements of developing monitoring protocols. However, important questions remain regarding the role that spatially explicit maps of aboveground biomass and carbon can play in IPCC-compliant forest monitoring systems, with the majority of these questions stemming from doubts about the inherit sensitivity of satellite data to aboveground forest biomass, confusion about the relationship between accuracy and resolution, and a general lack of guidance on optimal strategies for linking field reference and remote sensing data sources. Here we demonstrate the ability of a state-of-the-art satellite radar sensor, the Japanese ALOS/PALSAR, and a venerable optical platform, Landsat 5, to support large-area mapping of aboveground tropical woody biomass across a 153,000-km2 region in the southwestern Amazon

  12. Roofing as a source of nonpoint water pollution.

    PubMed

    Chang, Mingteh; McBroom, Matthew W; Scott Beasley, R

    2004-12-01

    Sixteen wooden structures with two roofs each were installed to study runoff quality for four commonly used roofing materials (wood shingle, composition shingle, painted aluminum, and galvanized iron) at Nacogdoches, Texas. Each roof, either facing NW or SE, was 1.22 m wide x 3.66 m long with a 25.8% roof slope. Thus, there were 32 alternatively arranged roofs, consisting of four roof types x two aspects x four replicates, in the study. Runoff from the roofs was collected through galvanized gutters, downspouts, and splitters. The roof runoff was compared to rainwater collected by a wet/dry acid rain collector for the concentrations of eight water quality variables, i.e. Cu(2+), Mn(2+), Pb(2+), Zn(2+), Mg(2+), Al(3+), EC and pH. Based on 31 storms collected between October 1997 and December 1998, the results showed: (1) concentrations of pH, Cu, and Zn in rainwater already exceed the EPA freshwater quality standards even without pollutant inputs from roofs, (2) Zn and Cu, the two most serious pollutants in roof runoff, exceeded the EPA national freshwater water quality standards in virtually 100% and more than 60% of the samples, respectively, (3) pH, EC, and Zn were the only three variables significantly affected by roofing materials, (4) differences in Zn concentrations were significant among all roof types and between all roof runoff and rainwater samples, (5) although there were no differences in Cu concentrations among all roof types and between roof runoff and rainwater, all means and medians of runoff and rainwater exceeded the national water quality standards, (6) water quality from wood shingles was the worst among the roof types studied, and (7) although SE is the most frequent and NW the least frequent direction for incoming storms, only EC, Mg, Mn, and Zn in wood shingle runoff from the SE were significantly higher than those from the NW; the two aspects affected no other elements in runoff from the other three roof types. Also, Zn concentrations from

  13. Impact of Sustainable Cool Roof Technology on Building Energy Consumption

    NASA Astrophysics Data System (ADS)

    Vuppuluri, Prem Kiran

    Highly reflective roofing systems have been analyzed over several decades to evaluate their ability to meet sustainability goals, including reducing building energy consumption and mitigating the urban heat island. Studies have isolated and evaluated the effects of climate, surface reflectivity, and roof insulation on energy savings, thermal load mitigation and also ameliorating the urban heat island. Other sustainable roofing systems, like green-roofs and solar panels have been similarly evaluated. The motivation for the present study is twofold: the first goal is to present a method for simultaneous evaluation and inter-comparison of multiple roofing systems, and the second goal is to quantitatively evaluate the realized heating and cooling energy savings associated with a white roof system compared to the reduction in roof-top heat flux. To address the first research goal a field experiment was conducted at the International Harvester Building located in Portland, OR. Thermal data was collected for a white roof, vegetated roof, and a solar panel shaded vegetated roof, and the heat flux through these roofing systems was compared against a control patch of conventional dark roof membrane. The second research goal was accomplished using a building energy simulation program to determine the impact of roof area and roof insulation on the savings from a white roof, in both Portland and Phoenix. The ratio of cooling energy savings to roof heat flux reduction from replacing a dark roof with a white roof was 1:4 for the month of July, and 1:5 annually in Portland. The COP of the associated chillers ranges from 2.8-4.2, indicating that the ratio of cooling energy savings to heat flux reduction is not accounted for solely by the COP of the chillers. The results of the building simulation indicate that based on energy savings alone, white roofs are not an optimal choice for Portland. The benefits associated with cooling energy savings relative to a black roof are offset by

  14. Aboveground Whitefly Infestation-Mediated Reshaping of the Root Microbiota

    PubMed Central

    Kong, Hyun G.; Kim, Byung K.; Song, Geun C.; Lee, Soohyun; Ryu, Choong-Min

    2016-01-01

    Plants respond to various types of herbivore and pathogen attack using well-developed defensive machinery designed for self-protection. Infestation from phloem-sucking insects such as whitefly and aphid on plant leaves was previously shown to influence both the saprophytic and pathogenic bacterial community in the plant rhizosphere. However, the modulation of the root microbial community by plants following insect infestation has been largely unexplored. Only limited studies of culture-dependent bacterial diversity caused by whitefly and aphid have been conducted. In this study, to obtain a complete picture of the belowground microbiome community, we performed high-speed and high-throughput next-generation sequencing. We sampled the rhizosphere soils of pepper seedlings at 0, 1, and 2 weeks after whitefly infestation versus the water control. We amplified a partial 16S ribosomal RNA gene (V1–V3 region) by polymerase chain reaction with specific primers. Our analysis revealed that whitefly infestation reshaped the overall microbiota structure compared to that of the control rhizosphere, even after 1 week of infestation. Examination of the relative abundance distributions of microbes demonstrated that whitefly infestation shifted the proteobacterial groups at week 2. Intriguingly, the population of Pseudomonadales of the class Gammaproteobacteria significantly increased after 2 weeks of whitefly infestation, and the fluorescent Pseudomonas spp. recruited to the rhizosphere were confirmed to exhibit insect-killing capacity. Additionally, three taxa, including Caulobacteraceae, Enterobacteriaceae, and Flavobacteriaceae, and three genera, including Achromobacter, Janthinobacterium, and Stenotrophomonas, were the most abundant bacterial groups in the whitefly infested plant rhizosphere. Our results indicate that whitefly infestation leads to the recruitment of specific groups of rhizosphere bacteria by the plant, which confer beneficial traits to the host plant. This

  15. Adapting Roof Support Methods for Anchoring Satellites on Asteroids

    NASA Astrophysics Data System (ADS)

    Speer, Grant B.

    The use of anchorage in satellite and spacecraft design has been largely restricted to harpoon-inspired technology based on anticipated low strengths of cometary and asteroid material. Initial results from the Rosetta mission to comet 67P/Churyumov- Gerasimenko, however, have demonstrated both larger-than-expected compressive strengths of cometary materials and the importance of adequate anchorage to mitigate the risk of mission failure. The field of rock mechanics can provide unique insight into the design of these satellite and lander anchors by drawing on existing roof bolt technology. This study compared the behavior of tensioned point anchor and untensioned fully-grouted roof bolts with a polyurethane-anchored bolt under environmental conditions similar to those anticipated in space. These conditions include variation in possible material types as well as variations in regolith properties, anchorage length, and low operating temperatures. Using a Box-Behnken experimental design, this study first compared the effects of anchor depth and rock strength on each of the three anchorage types in a competent rock strength regime. The study then examined the effects of compaction, water content, and temperature on each anchor type in a regolith environment. The subsequent data analysis identified one anchor type as the overall best anchor for these environments. This finding has led to a preliminary design recommendation to advise space agencies on satellite anchor construction based on the target orbital body's anticipated environmental and "exogeologic" conditions.

  16. Weathering of Roofing Materials-An Overview

    SciTech Connect

    Berdahl, Paul; Akbari, Hashem; Levinson, Ronnen; Miller, William A.

    2006-03-30

    An overview of several aspects of the weathering of roofing materials is presented. Degradation of materials initiated by ultraviolet radiation is discussed for plastics used in roofing, as well as wood and asphalt. Elevated temperatures accelerate many deleterious chemical reactions and hasten diffusion of material components. Effects of moisture include decay of wood, acceleration of corrosion of metals, staining of clay, and freeze-thaw damage. Soiling of roofing materials causes objectionable stains and reduces the solar reflectance of reflective materials. (Soiling of non-reflective materials can also increase solar reflectance.) Soiling can be attributed to biological growth (e.g., cyanobacteria, fungi, algae), deposits of organic and mineral particles, and to the accumulation of flyash, hydrocarbons and soot from combustion.

  17. In-situ aging of roof systems containing polyisocyanurate roof insulation foamed with alternative blowing agents

    SciTech Connect

    Desjarlais, A.O.; Christian, J.E.; Graves, R.S.

    1993-10-01

    Experimental polyisocyanurate (PIR) foam roof insulations with permeable facers were installed in roofing systems and continuously monitored for thermal performance for four years. The foams were produced using a specific formulation that represented current technology in 1989 and were blown with CFC-11, HCFC-123, and HCFC-141b. These foams were installed in roof systems comprised of loosely-laid insulation boards covered by either a loosely-laid single ply white or black membrane. The in-situ testing was carried out on an outdoor test facility, the Roof Thermal Research Apparatus (RTRA). Additional specimens of these foams were aged in the laboratory and periodically evaluated using laboratory measurement equipment. This paper summarizes the in-situ data compiled to date, compares these data with the laboratory results, and examines whether the proposed laboratory procedure for accelerating the aging of foams by the slicing and scaling method accurately predicts the aging characteristics of these materials installed in roof systems. These experiments are part of a joint industry/government project established to evaluate the technical viability of alternative HCFC blowing agents for rigid closed-cell polyisocyanurate foam roof insulations. Members of the project are the US Department of Energy (DOE)/Oak Ridge National Laboratory (ORNL), the US Environmental Protection Agency (EPA), the Society of the Plastics Industry-Polyurethane Division (SPI), the Polyisocyanurate Insulation Manufacturers Association (PIMA), and the National Roofing Contractors Association (NRCA).

  18. WIPP supplementary roof support system Room 1, Panel 1: Geotechnical field data analysis report

    SciTech Connect

    Not Available

    1993-03-01

    The design of the Room 1, Panel 1, supplementary roof support system was finalized in September 1991, and the system successfully installed in the test bin area between the bulkheads by December 1991. Simultaneously with the support system installation, existing monitoring system was upgraded to meet the needs of the installed roof support. This included extensometers, closure stations, rockbolt load cells as well as survey measurements of roof sag and floor lift. A Project Control Group (PCG) was established in order to monitor room and support system performance. Weekly meetings of the PCG were held to review all monitored data against criteria set in the initial design, and to modify these where necessary. Records of these meetings have been kept, with copies of all data summaries and action notes. These data records are maintained in the Engineering data files. After more than ten months of monitoring and reviewing experience, several modifications have been made both to the way data has been reported as well as to the load adjustment criteria. The support system has performed as expected in the design, with no signs of instability developing considering the rates of roof deformation, the rock bolt loads and the observed fracture behavior in the roof. This is particularly true of the horizon in which the rockbolt anchors are located, the most critical part of the design. The distribution of load build-up, throughout the 286 rockbolt load cells installed, in the Room 1 has been found satisfactory, and the load increases as evaluated by the PCG on a weekly basis have been within the acceptable range. The minimum life of the installed support system is estimated at 15 years based on the highest roof expansion rate experienced to date. This report provides analysis of geotechnical field data collected up to December 1992.

  19. 46. C. 1854 BUILDING ATTIC ROOF SPACE, VIEW OF KING ...

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

    46. C. 1854 BUILDING ATTIC ROOF SPACE, VIEW OF KING POST TRUSS ALONG LENGTH OF THE BUILDING. RAILS ON FLOOR FOR MOVEMENT OF GOODS STORED IN ROOF SPACE. - Continental Gin Company, Prattville, Autauga County, AL

  20. Thermoplastic Single-Ply Roof Relieves Water Damage and Inconvenience.

    ERIC Educational Resources Information Center

    Williams, Jennifer Lynn

    2002-01-01

    Assesses use of thermoplastic single-ply roofs by North Carolina's Mars Hill College to prevent leaks, reduce maintenance costs, and enhance the value of their older historic buildings. Administrators comment on the roof's installation efficiency and cleanliness. (GR)

  1. BLACKSMITH SHOP ROOF STRUCTURE AT JUNCTION BETWEEN 60 FT. AND ...

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

    BLACKSMITH SHOP ROOF STRUCTURE AT JUNCTION BETWEEN 60 FT. AND 90 FT. SPAN ROOF TRUSSES, LOOKING SOUTH. - Southern Pacific, Sacramento Shops, Blacksmith Shop, 111 I Street, Sacramento, Sacramento County, CA

  2. 30 CFR 75.221 - Roof control plan information.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... address of the company. (2) The name, address, mine identification number and location of the mine. (3... to be used in the roof, face and rib control system, including, if roof bolts are to be installed— (i...

  3. 13. INTERIOR OF TAN 629 HANGAR, TAKEN ON LOW ROOF ...

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

    13. INTERIOR OF TAN 629 HANGAR, TAKEN ON LOW ROOF ON WEST SIDE, FACING SOUTH. SHOWS SMC ROOF UTILITY PAD. - Idaho National Engineering Laboratory, Test Area North, Hangar No. 629, Scoville, Butte County, ID

  4. Eastern portal, looking W. Note hipped roof covered with wood ...

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

    Eastern portal, looking W. Note hipped roof covered with wood shingles, added in 1993. The hipped roof is unique in U.S. covered bridges. - Doe River Bridge, Spanning Doe River, Third Avenue, Elizabethton, Carter County, TN

  5. 5. ROOF DETAIL, LOOKING EAST TOWARD SECOND FLOOR WAREHOUSE FROM ...

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

    5. ROOF DETAIL, LOOKING EAST TOWARD SECOND FLOOR WAREHOUSE FROM ROOF OF ASSEMBLY AREA. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  6. The Map to Cost-Effective Summer Roofing.

    ERIC Educational Resources Information Center

    Waldron, Larry W.

    1988-01-01

    Roofing is one of the major expense items in school district maintenance budgets. Outlines steps to take in project planning, developing budget estimates and specifications, and completing a roofing project on time. (MLF)

  7. Thermoplastic Single-Ply Roof Relieves Water Damage and Inconvenience.

    ERIC Educational Resources Information Center

    Williams, Jennifer Lynn

    2002-01-01

    Assesses use of thermoplastic single-ply roofs by North Carolina's Mars Hill College to prevent leaks, reduce maintenance costs, and enhance the value of their older historic buildings. Administrators comment on the roof's installation efficiency and cleanliness. (GR)

  8. Roofs That Last...And Last...And Last.

    ERIC Educational Resources Information Center

    Fickes, Michael

    1999-01-01

    Describes the benefits of using protected membrane roofing (PMR) systems as a means of cutting maintenance and repair costs over the roof's lifetime. Addresses responses to arguments against using PMR systems. (GR)

  9. Interior view of the Sheet Metal Shop showing the roof ...

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

    Interior view of the Sheet Metal Shop showing the roof trusses and corrugated metal roof covering, view facing northwest - Kahului Cannery, Plant No. 28, Boiler House, Sheet Metal and Electrical Shops, 120 Kane Street, Kahului, Maui County, HI

  10. 46. OCTAGONAL & WEST TOWERS FROM SOUTH TOWER ROOF, LOOKING ...

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

    46. OCTAGONAL & WEST TOWERS FROM SOUTH TOWER ROOF, LOOKING NORTHWEST, WITH WEST WING ROOF - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  11. 42. SOUTHEAST TOWER & EAST WING ROOF FROM SOUTH TOWER ...

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

    42. SOUTHEAST TOWER & EAST WING ROOF FROM SOUTH TOWER ROOF, LOOKING EAST BY NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  12. 14. DETAIL OF ROOF SUPPORT BEAMS BRACED AGAINST HEXAGONAL WOODEN ...

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

    14. DETAIL OF ROOF SUPPORT BEAMS BRACED AGAINST HEXAGONAL WOODEN COMPRESSION RING AT TOP OF CENTRAL ROOF TRUSS. - Saratoga Gas Light Company, Gasholder No. 2, Niagara Mohawk Power Corporation Substation Facility, intersection of Excelsior & East Avenues, Saratoga Springs, NY

  13. Inventory of Tank Farm equipment stored or abandoned aboveground

    SciTech Connect

    Hines, S.C.; Lakes, M.E.

    1994-10-12

    This document provides an inventory of Tank Farm equipment stored or abandoned aboveground and potentially subject to regulation. This inventory was conducted in part to ensure that Westinghouse Hanford Company (WHC) does not violate dangerous waste laws concerning storage of potentially contaminated equipment/debris that has been in contact with dangerous waste. The report identifies areas inventoried and provides photographs of equipment.

  14. WEAPONS STORAGE AREA. FROM RIGHT TO LEFT, ABOVEGROUND STORAGE MAGAZINE ...

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

    WEAPONS STORAGE AREA. FROM RIGHT TO LEFT, ABOVEGROUND STORAGE MAGAZINE (BUILDING 3568), SPARES INERT STORAGE BUILDING (BUILDING 3570), MISSILE ASSEMBLY SHOP (BUILDING 3578) AND SEGREGATED MAGAZINE STORAGE BUILDING (BUILDING 3572). VIEW TO NORTHWEST - Plattsburgh Air Force Base, U.S. Route 9, Plattsburgh, Clinton County, NY

  15. Family Differences Influence the Aboveground Biomass of Loblolly Pine Plantations

    Treesearch

    P.E. Pope; D.L. Graney

    1979-01-01

    We compared the aboveground biomass of 4 half-sib families of loblolly pine (Pinus taeda L.) 11 years after planting. Total dry weights differed significantly among families in plantations on the same soil type with the same site index. Differences in biomass resulted from differences in stem form and branch size. Distribution of growth -the proportion of tree weight...

  16. Aboveground growth interactions of paired conifer seedlings in close proximity

    Treesearch

    Warren D. Devine; Timothy B. Harrington

    2011-01-01

    Where belowground resources are relatively abundant, naturally established trees sometimes occur in very close proximity to one another. We conducted a two-year study to assess the aboveground interactions between Douglas-fir (Pseudotsuga menziesii), grand fir (Abies grandis) and noble fir (Abies procera)...

  17. Family Differences in Aboveground Biomass Allocation in Loblolly Pine

    Treesearch

    Scott D. Roberts

    2002-01-01

    The proportion of tree growth allocated to stemwood is an important economic component of growth efficiency. Differences in growth efficiency between species, or between families within species, may therefore be related to how growth is proportionally allocated between the stem and other aboveground biomass components. This study examines genetically related...

  18. Identifying aboveground wood fiber potentials in New York State

    Treesearch

    Eric H. Wharton

    1984-01-01

    New York forests are made up of more than just the growing stock that is measured during conventional forest inventories. A biomass inventory, completed in 1980, showed that New York commercial forest lands contain nearly 1,164.4 million green tons of aboveground tree biomass, or an average of 75.6 green tons per acre. Conventional growing stock accounted for 57...

  19. Estimates of forest canopy height and aboveground biomass using ICESat.

    Treesearch

    Michael A. Lefsky; David J. Harding; Michael Keller; Warren B. Cohen; Claudia C. Carabajal; Fernando Del Bom; Maria O. Hunter; Raimundo Jr. de Oliveira

    2005-01-01

    Exchange of carbon between forests and the atmosphere is a vital component of the global carbon cycle. Satellite laser altimetry has a unique capability for estimating forest canopy height, which has a direct and increasingly well understood relationship to aboveground carbon storage. While the Geoscience Laser Altimeter System (GLAS) onboard the Ice, Cloud and land...

  20. Forecasting annual aboveground net primary production in the intermountain west

    USDA-ARS?s Scientific Manuscript database

    For many land manager’s annual aboveground net primary production, or plant growth, is a key factor affecting business success, profitability and each land manager's ability to successfully meet land management objectives. The strategy often utilized for forecasting plant growth is to assume every y...

  1. Assessing aboveground tropical forest biomass using Google Earth canopy images.

    PubMed

    Ploton, Pierre; Pélissier, Raphaël; Proisy, Christophe; Flavenot, Théo; Barbier, Nicolas; Rai, S N; Couteron, Pierre

    2012-04-01

    Reducing Emissions from Deforestation and Forest Degradation (REDD) in efforts to combat climate change requires participating countries to periodically assess their forest resources on a national scale. Such a process is particularly challenging in the tropics because of technical difficulties related to large aboveground forest biomass stocks, restricted availability of affordable, appropriate remote-sensing images, and a lack of accurate forest inventory data. In this paper, we apply the Fourier-based FOTO method of canopy texture analysis to Google Earth's very-high-resolution images of the wet evergreen forests in the Western Ghats of India in order to (1) assess the predictive power of the method on aboveground biomass of tropical forests, (2) test the merits of free Google Earth images relative to their native commercial IKONOS counterparts and (3) highlight further research needs for affordable, accurate regional aboveground biomass estimations. We used the FOTO method to ordinate Fourier spectra of 1436 square canopy images (125 x 125 m) with respect to a canopy grain texture gradient (i.e., a combination of size distribution and spatial pattern of tree crowns), benchmarked against virtual canopy scenes simulated from a set of known forest structure parameters and a 3-D light interception model. We then used 15 1-ha ground plots to demonstrate that both texture gradients provided by Google Earth and IKONOS images strongly correlated with field-observed stand structure parameters such as the density of large trees, total basal area, and aboveground biomass estimated from a regional allometric model. Our results highlight the great potential of the FOTO method applied to Google Earth data for biomass retrieval because the texture-biomass relationship is only subject to 15% relative error, on average, and does not show obvious saturation trends at large biomass values. We also provide the first reliable map of tropical forest aboveground biomass predicted

  2. [Aboveground architecture and biomass distribution of Quercus variabilis].

    PubMed

    Yu, Bi-yun; Zhang, Wen-hui; Hu, Xiao-jing; Shen, Jia-peng; Zhen, Xue-yuan; Yang, Xiao-zhou

    2015-08-01

    The aboveground architecture, biomass and its allocation, and the relationship between architecture and biomass of Quercus variabilis of different diameter classes in Shangluo, south slope of Qinling Mountains were researched. The results showed that differences existed in the aboveground architecture and biomass allocation of Q. variabilis of different diameter classes. With the increase of diameter class, tree height, DBH, and crown width increased gradually. The average decline rate of each diameter class increased firstly then decreased. Q. variabilis overall bifurcation ratio and stepwise bifurcation ratio increased then declined. The specific leaf areas of Q. variabilis of all different diameter classes at vertical direction were 0.02-0.03, and the larger values of leaf mass ratio, LAI and leaf area ratio at vertical direction in diameter level I , II, III appeared in the middle and upper trunk, while in diameter level IV, V, VI, they appeared in the central trunk, with the increase of diameter class, there appeared two peaks in vertical direction, which located in the lower and upper trunk. The trunk biomass accounted for 71.8%-88.4% of Q. variabilis aboveground biomass, while the branch biomass accounted for 5.8%-19.6%, and the leaf biomass accounted for 4.2%-8.6%. With the increase of diameter class, stem biomass proportion of Q. variabilis decreased firstly then increased, while the branch and leaf biomass proportion showed a trend that increased at first then decreased, and then increased again. The aboveground biomass of Q. variabilis was significantly positively correlated to tree height, DBH, crown width and stepwise bifurcation ratio (R2:1), and positively related to the overall bifurcation ratio and stepwise bifurcation ratio (R3:2), but there was no significant correlation. Trunk biomass and total biomass aboveground were negatively related to the trunk decline rate, while branch biomass and leaf biomass were positively related to trunk decline

  3. Analysis of Wind Forces on Roof-Top Solar Panel

    NASA Astrophysics Data System (ADS)

    Panta, Yogendra; Kudav, Ganesh

    2011-03-01

    Structural loads on solar panels include forces due to high wind, gravity, thermal expansion, and earthquakes. International Building Code (IBC) and the American Society of Civil Engineers are two commonly used approaches in solar industries to address wind loads. Minimum Design Loads for Buildings and Other Structures (ASCE 7-02) can be used to calculate wind uplift loads on roof-mounted solar panels. The present study is primarily focused on 2D and 3D modeling with steady, and turbulent flow over an inclined solar panel on the flat based roof to predict the wind forces for designing wind management system. For the numerical simulation, 3-D incompressible flow with the standard k- ɛ was adopted and commercial CFD software ANSYS FLUENT was used. Results were then validated with wind tunnel experiments with a good agreement. Solar panels with various aspect ratios for various high wind speeds and angle of attacks were modeled and simulated in order to predict the wind loads in various scenarios. The present study concluded to reduce the strong wind uplift by designing a guide plate or a deflector before the panel. Acknowledgments to Northern States Metal Inc., OH (GK & YP) and School of Graduate Studies of YSU for RP & URC 2009-2010 (YP).

  4. 29 CFR 570.67 - Occupations in roofing operations and on or about a roof (Order 16).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... pitch, asphalt prepared paper, tile, composite roofing materials, slate, metal, translucent materials..., roofing helper, materials handler and tending a tar heater. (c) Exemptions. This section shall not apply...) and (c)....

  5. 29 CFR 570.67 - Occupations in roofing operations and on or about a roof (Order 16).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pitch, asphalt prepared paper, tile, composite roofing materials, slate, metal, translucent materials..., roofing helper, materials handler and tending a tar heater. (c) Exemptions. This section shall not apply...) and (c)....

  6. ROOFER Inventory Procedures and Inspection Manual for Metal Panel Roofing

    DTIC Science & Technology

    2012-12-01

    from the NRCA Roofing Manual: Metal Panel and SPF Roof Systems – 2012, with the permission of the Na- tional Roofing Contractor Association (NRCA...RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE ( DD -MM-YYYY) December 2012 2. REPORT TYPE Final 3. DATES COVERED (From - To) 4. TITLE

  7. 30 CFR 75.213 - Roof support removal.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... persons who perform the work of removing permanent roof supports shall be supervised by a management... mining experience shall perform permanent roof support removal work. (b) Prior to the removal of... where— (1) Roof bolt torque or tension measurements or the condition of conventional support...

  8. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a... they are closed. (iii) Except for automatic bleeder vents, rim space vents, roof drains, and leg... and rim space vents shall be equipped with a gasket. (v) Each roof drain that empties into the...

  9. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a... they are closed. (iii) Except for automatic bleeder vents, rim space vents, roof drains, and leg... and rim space vents shall be equipped with a gasket. (v) Each roof drain that empties into the...

  10. 49 CFR 238.441 - Emergency roof access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Emergency roof access. 238.441 Section 238.441... Equipment § 238.441 Emergency roof access. (a) Existing passenger cars and power cars. Each passenger car..., 2011, shall have a minimum of one roof hatch emergency access location with a minimum opening of...

  11. 49 CFR 238.123 - Emergency roof access.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Emergency roof access. 238.123 Section 238.123... § 238.123 Emergency roof access. Except as provided in § 238.441 of this chapter— (a) Number and... or after April 1, 2011, shall have a minimum of two emergency roof access locations, each with...

  12. 49 CFR 238.123 - Emergency roof access.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Emergency roof access. 238.123 Section 238.123... § 238.123 Emergency roof access. Except as provided in § 238.441 of this chapter— (a) Number and... or after April 1, 2011, shall have a minimum of two emergency roof access locations, each with...

  13. Which Roof is Tops? Grades PreK-2.

    ERIC Educational Resources Information Center

    Rushton, Erik; Ryan, Emily; Swift, Charles

    This introductory activity explores the advantages of different roof shapes for different climates or situations. It addresses questions such as "When you walk or drive around your neighborhood, what do the roofs look like?" and "What if you lived in an area with a different climate, how would that affect the style of roof that you might find?"…

  14. 49 CFR 238.441 - Emergency roof access.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Emergency roof access. 238.441 Section 238.441... Equipment § 238.441 Emergency roof access. (a) Existing passenger cars and power cars. Each passenger car..., 2011, shall have a minimum of one roof hatch emergency access location with a minimum opening of...

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

    SciTech Connect

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

    1984-02-02

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

  16. Full-scale tests of wind effects on a long span roof structure

    NASA Astrophysics Data System (ADS)

    Fu, Jiyang; Zheng, Qingxing; Wu, Jiurong; Xu, An

    2015-06-01

    Full-scale measurements are regarded as the most reliable method to evaluate wind effects on large buildings and structures. Some selected results are presented in this paper from the full-scale measurement of wind effects on a long-span steel roof structure during the passage of Typhoon Fanapi. Some field data, including wind speed and direction, acceleration responses, etc., were continuously and simultaneously recorded during the passage of the typhoon. Comprehensive analysis of the measured data is conducted to evaluate the typhoon-generated wind characteristics and its effects on a long-span steel roof. The first four natural frequencies and their vibration mode shapes of the Guangzhou International Sports Arena (GISA) roof are evaluated by the stochastic subspace identification (SSI) method and comparisons with those from finite element (FE) analysis are made. Meanwhile, damping ratios of the roof are also identified by the SSI method and compared with those identified by the random decrement method; the amplitude-dependent damping behaviors are also discussed. The fullscale measurement results are further compared with the corresponding wind tunnel test results to evaluate its reliability. The results obtained from this study are valuable for academic and professional engineers involved in the design of large-span roof structures.

  17. The growth and survival of plants in urban green roofs in a dry climate.

    PubMed

    Razzaghmanesh, M; Beecham, S; Kazemi, F

    2014-04-01

    Green roofs as one of the components of water-sensitive urban design have become widely used in recent years. This paper describes performance monitoring of four prototype-scale experimental green roofs in a northern suburb of Adelaide, South Australia, undertaken over a 1-year period. Four species of indigenous Australian ground cover and grass species comprising Carpobrotus rossii, Lomandra longifolia 'Tanika,' Dianella caerula 'Breeze' and Myoporum parvifolium were planted in extensive and intensive green roof configurations using two different growing media. The first medium consisted of crushed brick, scoria, coir fibre and composted organics while the second comprised scoria, composted pine bark and hydro-cell flakes. Plant growth indices including vertical and horizontal growth rate, leaf succulence, shoot and root biomasses, water use efficiency and irrigation regimes were studied during a 12-month period. The results showed that the succulent species, C. rossii, can best tolerate the hot, dry summer conditions of South Australia, and this species showed a 100% survival rate and had the maximum horizontal growth rate, leaf succulence, shoot biomass and water use efficiency. All of the plants in the intensive green roofs with the crushed brick mix media survived during the term of this study. It was shown that stormwater can be used as a source of irrigation water for green roofs during 8 months of the year in Adelaide. However, supplementary irrigation is required for some of the plants over a full annual cycle. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... drains, each opening shall be equipped with a gasketed cover or gasketed lid. (iii) Each penetration of... cover, access hatch, gauge float well, or lid on any opening in the internal floating roof shall...

  19. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... drains, each opening shall be equipped with a gasketed cover or gasketed lid. (iii) Each penetration of... cover, access hatch, gauge float well, or lid on any opening in the internal floating roof shall...

  20. Assessment of a fiber-optic distributed-temperature-sensing system to monitor the thermal dynamics of vegetated roof

    NASA Astrophysics Data System (ADS)

    Cousiño, J. A.; Hausner, M. B.; Victorero, F.; Bonilla, C.; Gironas, J. A.; Vera, S.; Bustamante, W.; Rojas, V.; Pasten, P.; Suarez, F. I.

    2014-12-01

    Vegetated (green) roofs include a growing media and vegetation layer, and offer a range of benefits such as the reduction of: the heat island effect, rooftop runoff peak flows, roof surface temperatures, energy used for cooling or heating buildings, and noise levels inside infrastructures. Vegetated roofs also offer aesthetic benefits and increase the biodiversity of the urban environment, and are increasingly used in sustainable urban development. Understanding the thermal dynamics of vegetated roofs will make it possible to improve their design and to better assess their impacts on energy efficiency. Here, we evaluate the first vertical high-resolution distributed-temperature-sensing (DTS) system installed in a vegetated roof. This system allows a continuous measurement of the thermal profile within a vegetated roof - going from the interior, upward through the drainage layers and soil substrate of the vegetated roof and ending in the air above the vegetation. Temperatures can be observed as frequently as every 30 s at a spatial resolution on the order of centimeters. This DTS system was installed in the "Laboratory of Vegetal Infrastructure of Buildings" (LIVE - its acronym in Spanish), located in the San Joaquín Campus of the Pontifical Catholic University, Santiago, Chile. The laboratory features 18 experimental modules to investigate different configurations of the vegetated roof layers. The LIVE was designed with the installation of the optical fibers in mind, and the DTS system allows simultaneous monitoring of three or four modules of the LIVE. In this work, we describe the design of this DTS deployment, the calibration metrics obtained using the software provided by the manufacturers, and other calibration algorithms previously developed. We compare the results obtained using single- and double-ended measurements, highlighting strengths and weaknesses of DTS methods. Finally, we present the observations obtained from this biophysical environment

  1. Practical aspects of mobile roof support usage

    SciTech Connect

    Chase, F.E.; Mark, C.; Barczak, T.M.

    1996-12-01

    Mobile roof supports are shield-type support units mounted on crawler tracks. Mobile roof support (MRS) units are used during retreat mining, and they eliminate the setting of roadway, turn, and crosscut breaker posts which are required during pillar recovery operations. Mobiles are a more effective ground support than timbers, and their usage enhance the safety of section personnel and reduces material handling injuries. MRS usage is rapidly increasing, and approximately 40 U.S. coal mines have successfully employed this relatively new technology. This paper is in response to increasing requests from operators, State and Federal Regulatory Agencies, and others on the practical aspects of MRS usage in underground coal mines. During this investigation, nearly half of the U.S. mines which have utilized mobiles were visited. This report depicts the more common pillar extraction methods which operators have found success. The Christmas tree and outside lift methods are illustrated and discussed. Roof control plans that do not require breaker posts or allow pillar extraction with fewer than four mobiles are also examined. In addition, operators` experiences with setting pressures, loads, and rates of loading during pillar extraction are addressed. Mining and support strategies to more effectively control hillseams, weak roof, and gob overrides which have entrapped equipment are also discussed.

  2. Waste and Abuse: Public School Roofing Projects.

    ERIC Educational Resources Information Center

    2000

    This report details the results of a comprehensive inquiry by New Jersey into one aspect of school construction, the repair and replacement of roof systems, which represents the single most expensive and integral component of a school's physical structure. The investigation began in late 1997 after confidential complaints suggested abuse in the…

  3. Thrust bolting: roof bolt support apparatus

    DOEpatents

    Tadolini, Stephen C.; Dolinar, Dennis R.

    1992-01-01

    A method of installing a tensioned roof bolt in a borehole of a rock formation without the aid of a mechanical anchoring device or threaded tensioning threads by applying thrust to the bolt (19) as the bonding material (7') is curing to compress the strata (3) surrounding the borehole (1), and then relieving the thrust when the bonding material (7') has cured.

  4. Roofing with Urethane: Pro and Con.

    ERIC Educational Resources Information Center

    Kinzer, Michael; Scott, Gerald P.E.

    1981-01-01

    Gerald Scott's favorable evaluation of the foamed polyurethane roofing system is based on experiences with 55 buildings at Texas A & M. Michael Kinzer, an architect at Colorado State University, disagrees and claims that the system is difficult to install and maintain, and the cost prohibitive. (MLF)

  5. Update on the Million Solar Roofs Initiative

    SciTech Connect

    Herig, C.

    1999-05-09

    The Million Solar Roofs Initiative, announced by the President in June of 1997, spans a period of twelve years and intends to increase domestic deployment of solar technologies. This paper presents an overview of the development of the initiative and significant activities to date.

  6. Roof Shield for Advance and Retreat Mining

    NASA Technical Reports Server (NTRS)

    Lewis, E. V.

    1985-01-01

    Shield sections change their configuration to suit mining mode. Articulation cylinders raise rear shield to advance position, and locking cylinders hold it there. To change to retreat position articulation cylinders lower shield. Locking pins at edge of outermost shield plate latch shield to chock base. Shield accommodates roof heights ranging from 36 to 60 inches (0.9 to 1.52 meters).

  7. Roofing with Urethane: Pro and Con.

    ERIC Educational Resources Information Center

    Kinzer, Michael; Scott, Gerald P.E.

    1981-01-01

    Gerald Scott's favorable evaluation of the foamed polyurethane roofing system is based on experiences with 55 buildings at Texas A & M. Michael Kinzer, an architect at Colorado State University, disagrees and claims that the system is difficult to install and maintain, and the cost prohibitive. (MLF)

  8. 7 CFR 2902.11 - Roof coatings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... single-coat monolith coating system. (b) Minimum biobased content. The minimum biobased content is 20... content product. Qualifying biobased products that fall under this item may, in some cases, overlap with... determining whether or not a qualifying biobased product overlaps with recovered content roofing materials and...

  9. 7 CFR 2902.11 - Roof coatings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... single-coat monolith coating system. (b) Minimum biobased content. The minimum biobased content is 20... content product. Qualifying biobased products that fall under this item may, in some cases, overlap with... determining whether or not a qualifying biobased product overlaps with recovered content roofing materials and...

  10. Environmental assessment of extensive green roofs in the UK

    NASA Astrophysics Data System (ADS)

    Ruan, Fei

    The advantages of the planted roofs are undoubtedly numerous from both the ecological and the social point of view. They act positively upon the climate of the city and its region, as well as upon the interior climate of the building beneath them. This dissertation, therefore, explores the environmental performance of the extensive green roofs in UK. The investigation was implemented in two phases: during the first phase, detailed introduction of green roofs with the emphasis on their thermal properties and behavior is provided with the support of literature review evidence. During the second phase of the study, the thermal properties of the green roof, as well as, the energy saving were examined, through two computer programs: Wufi and TAS. Two hypothetic models have been developed in these programs to evaluate thermal and energy performances of a building with a green roof, varying different parameters for the green roof or changing different internal condition for the building. The main conclusion of these analyses is that two parameters: vegetation solar absorptivity and water content of green roofs play significant role in the thermal performance of green roofs. Lower vegetation solar absorptivity and higher water content will help green roofs to further reduce the external heat flux and summer inward heat flux which consequently mitigate the urban heat island effect and summer energy consumption. On the other hand, in comparison with the traditional roofs, green roofs appear to have less heating loads but higher cooling loads when internal gain is higher. Finally, when comparing Wufi results to TAS results, both represent that featured as lower solar absorptivity and higher insulation value, green roofs do alleviate the urban heat island effect and reduce the heat flux through the roof. Nevertheless, by taking account of evaporative cooling effect of green roofs, Wufi provides a more accurate approach to simulate the performance of green roofs

  11. A field study to evaluate the impact of different factors on the nutrient pollutant concentrations in green roof runoff.

    PubMed

    Wang, Xiaochen; Zhao, Xinhua; Peng, Chenrui; Zhang, Xinbo; Wang, Jianghai

    2013-01-01

    The objectives of this study are to investigate the impact of different factors on the nutrient pollutant concentrations in green roof runoff and to provide reference data for the engineering design of dual substrate layer green roofs. The data were collected from eight different trays under three kinds of artificial rains. The results showed that except for total phosphorus, dual substrate layer green roofs behaved as a sink for most of the nutrient pollutants (significant at p < 0.05), and the first-flush effect did not occur during the 27 simulated rain events. The results also revealed that the concentration of these nutrient pollutants in the runoff strongly depended on the features of the nutrient substrates used in the green roof and the depth of the adsorption substrates. Compared with the influence of the substrates, the influence of the plant density and drainage systems was small.

  12. The role of above-ground competition and nitrogen vs. phosphorus enrichment in seedling survival of common European plant species of semi-natural grasslands.

    PubMed

    Ceulemans, Tobias; Hulsmans, Eva; Berwaers, Sigi; Van Acker, Kasper; Honnay, Olivier

    2017-01-01

    Anthropogenic activities have severely altered fluxes of nitrogen and phosphorus in ecosystems worldwide. In grasslands, subsequent negative effects are commonly attributed to competitive exclusion of plant species following increased above-ground biomass production. However, some studies have shown that this does not fully account for nutrient enrichment effects, questioning whether lowering competition by reducing grassland productivity through mowing or herbivory can mitigate the environmental impact of nutrient pollution. Furthermore, few studies so far discriminate between nitrogen and phosphorus pollution. We performed a full factorial experiment in greenhouse mesocosms combining nitrogen and phosphorus addition with two clipping regimes designed to relax above-ground competition. Next, we studied the survival and growth of seedlings of eight common European grassland species and found that five out of eight species showed higher survival under the clipping regime with the lowest above-ground competition. Phosphorus addition negatively affected seven plant species and nitrogen addition negatively affected four plant species. Importantly, the negative effects of nutrient addition and higher above-ground competition were independent of each other for all but one species. Our results suggest that at any given level of soil nutrients, relaxation of above-ground competition allows for higher seedling survival in grasslands. At the same time, even at low levels of above-ground competition, nutrient enrichment negatively affects survival as compared to nutrient-poor conditions. Therefore, although maintaining low above-ground competition appears essential for species' recruitment, for instance through mowing or herbivory, these management efforts are likely to be insufficient and we conclude that environmental policies aimed to reduce both excess nitrogen and particularly phosphorus inputs are also necessary.

  13. The role of above-ground competition and nitrogen vs. phosphorus enrichment in seedling survival of common European plant species of semi-natural grasslands

    PubMed Central

    Ceulemans, Tobias; Hulsmans, Eva; Berwaers, Sigi; Van Acker, Kasper; Honnay, Olivier

    2017-01-01

    Anthropogenic activities have severely altered fluxes of nitrogen and phosphorus in ecosystems worldwide. In grasslands, subsequent negative effects are commonly attributed to competitive exclusion of plant species following increased above-ground biomass production. However, some studies have shown that this does not fully account for nutrient enrichment effects, questioning whether lowering competition by reducing grassland productivity through mowing or herbivory can mitigate the environmental impact of nutrient pollution. Furthermore, few studies so far discriminate between nitrogen and phosphorus pollution. We performed a full factorial experiment in greenhouse mesocosms combining nitrogen and phosphorus addition with two clipping regimes designed to relax above-ground competition. Next, we studied the survival and growth of seedlings of eight common European grassland species and found that five out of eight species showed higher survival under the clipping regime with the lowest above-ground competition. Phosphorus addition negatively affected seven plant species and nitrogen addition negatively affected four plant species. Importantly, the negative effects of nutrient addition and higher above-ground competition were independent of each other for all but one species. Our results suggest that at any given level of soil nutrients, relaxation of above-ground competition allows for higher seedling survival in grasslands. At the same time, even at low levels of above-ground competition, nutrient enrichment negatively affects survival as compared to nutrient-poor conditions. Therefore, although maintaining low above-ground competition appears essential for species’ recruitment, for instance through mowing or herbivory, these management efforts are likely to be insufficient and we conclude that environmental policies aimed to reduce both excess nitrogen and particularly phosphorus inputs are also necessary. PMID:28333985

  14. Status of cool roof standards in the United States

    SciTech Connect

    Akbari, Hashem; Levinson, Ronnen

    2007-06-01

    Since 1999, several widely used building energy efficiency standards, including ASHRAE 90.1, ASHRAE 90.2, the International Energy Conservation Code, and California's Title 24 have adopted cool roof credits or requirements. We review the technical development of cool roof provisions in the ASHRAE 90.1, ASHRAE 90.2, and California Title 24 standards, and discuss the treatment of cool roofs in other standards and energy-efficiency programs. The techniques used to develop the ASHRAE and Title 24 cool roof provisions can be used as models to address cool roofs in building energy standards worldwide.

  15. Housing conditions and Plasmodium falciparum infection: protective effect of iron-sheet roofed houses.

    PubMed

    Yé, Yazoumé; Hoshen, Moshe; Louis, Valérie; Séraphin, Simboro; Traoré, Issouf; Sauerborn, Rainer

    2006-02-01

    Identification and better understanding of potential risk factors for malaria are important for targeted and cost-effective health interventions. Housing conditions have been suggested as one of the potential risk factors. This study aims to further investigate this risk factor, and is focused on the effect of the type of roof on Plasmodium falciparum infection among children below five years in the North West of Burkina Faso. In a cross-sectional study design, 661 children aged six to 60 months were randomly selected from three rural and one semi-urban site at the end of the rainy season (November 2003). The children were screened for fever and tested for Plasmodium falciparum infection. In addition, data on bed net use and house characteristics was collected from the household were each child lived. Using adjusted odds ratios, children living in house roofed with iron-sheet were compared with those in house with mud or grass roof. Overall P. falciparum infection prevalence was 22.8 % with a significant variation between (Chi-square, p < 0.0001). The prevalence in Cissé (33.3 %) and Goni (30.6 %) were twice times more than in Nouna (15.2 %) and Kodougou (13.2 %). After adjusting for age, sex, use of bed net and housing conditions, children living in houses with mud roofs had significantly higher risk of getting P. falciparum infection compared to those living in iron-sheet roofed houses (Odds Ratio 2.6; 95% Confidence Interval, 1.4-4.7). These results suggest that house characteristics should be taken into consideration when designing health intervention against P. falciparum infection and particular attention should be paid to children living in houses with mud roofs.

  16. Philips and BASF put a new spin on the car roof

    NASA Astrophysics Data System (ADS)

    Halper, Mark

    2012-03-01

    At first glance it may look more like a fancy paint job but a new car roof designed by researchers at Philips and chemical giant BASF has the unusual property of giving drivers and passengers a clear view by day before turning into an interior light at night.

  17. Evaluation of the High-Heel Roof-to-Wall Connection with Extended OSB Wall Sheathing

    Treesearch

    Andrew DeRenzis; Vladimir Kochkin; Xiping Wang

    2013-01-01

    A recently completed testing project conducted to evaluate optimized structural roof-to-wall attachment solutions demonstrated the effectiveness of wood structural panels in restraining high-heel trusses against rotation. This study was designed to further evaluate the performance of OSB wall sheathing panels extended over the high-heel truss in resisting combined...

  18. A new look at moisture control in low slope roofing

    SciTech Connect

    Desjarlais, A.O.; Byars, N.A.

    1997-03-01

    One of the criteria for a moisture-tolerant roof is that moisture accumulation in a roofing system must not be large enough to cause condensation within the roof, since this can damage the insulation and reduce its effectiveness. Failing this criterion would require the inclusion of a vapor retarder into the roofing system. We have tested this requirement using computer simulations for a series of new roofing systems and environmental conditions. This paper uses the database from those simulations to develop a simplified method to predict condensation control using only variables associated with the roof and environmental conditions. This method assesses the potential for condensation within the roof assembly without having to perform a computer simulation. Using the computer simulation output data, the moisture accumulation inside each of the roofing systems was calculated. A critical threshold of moisture accumulation was assigned by analyzing the roofing systems which fail to prevent condensation from occurring within the roofing system. An empirical equation for moisture accumulation as a function of roof system and environmental condition variables is developed. The moisture accumulation calculated using this relationship correlates well with the moisture accumulation based on the results of computer simulations. The ability of these two different relationships for moisture accumulation to predict condensation control using the established critical threshold is assessed. Accuracy of both methods is over 95%.

  19. Green roofs as a means of pollution abatement.

    PubMed

    Rowe, D Bradley

    2011-01-01

    Green roofs involve growing vegetation on rooftops and are one tool that can help mitigate the negative effects of pollution. This review encompasses published research to date on how green roofs can help mitigate pollution, how green roof materials influence the magnitude of these benefits, and suggests future research directions. The discussion concentrates on how green roofs influence air pollution, carbon dioxide emissions, carbon sequestration, longevity of roofing membranes that result in fewer roofing materials in landfills, water quality of stormwater runoff, and noise pollution. Suggestions for future directions for research include plant selection, development of improved growing substrates, urban rooftop agriculture, water quality of runoff, supplemental irrigation, the use of grey water, air pollution, carbon sequestration, effects on human health, combining green roofs with complementary related technologies, and economics and policy issues. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Establishing Green Roof Infrastructure Through Environmental Policy Instruments

    NASA Astrophysics Data System (ADS)

    Carter, Timothy; Fowler, Laurie

    2008-07-01

    Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated

  1. Establishing green roof infrastructure through environmental policy instruments.

    PubMed

    Carter, Timothy; Fowler, Laurie

    2008-07-01

    Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated

  2. Aboveground tree biomass on productive forest land in Alaska.

    Treesearch

    John Yarie; Delbert. Mead

    1982-01-01

    Total aboveground woody biomass of trees on forest land that can produce 1.4 cubic m eters per hectare per year of industrial wood in Alaska is 1.33 billion metric tons green weight. The estimated energy value of the standing woody biomass is 11.9 x 10'5 Btu's. Statewide tables of biomass and energy values for softwoods, hardwoods, and species groups are...

  3. Potato tuber herbivory increases resistance to aboveground lepidopteran herbivores.

    PubMed

    Kumar, Pavan; Ortiz, Erandi Vargas; Garrido, Etzel; Poveda, Katja; Jander, Georg

    2016-09-01

    Plants mediate interactions between aboveground and belowground herbivores. Although effects of root herbivory on foliar herbivores have been documented in several plant species, interactions between tuber-feeding herbivores and foliar herbivores are rarely investigated. We report that localized tuber damage by Tecia solanivora (Guatemalan tuber moth) larvae reduced aboveground Spodoptera exigua (beet armyworm) and Spodoptera frugiperda (fall armyworm) performance on Solanum tuberosum (potato). Conversely, S. exigua leaf damage had no noticeable effect on belowground T. solanivora performance. Tuber infestation by T. solanivora induced systemic plant defenses and elevated resistance to aboveground herbivores. Lipoxygenase 3 (Lox3), which contributes to the synthesis of plant defense signaling molecules, had higher transcript abundance in T. solanivora-infested leaves and tubers than in equivalent control samples. Foliar expression of the hydroxycinnamoyl-CoA quinate hydroxycinnamoyl transferase (HQT) and 3-hydroxy-3-methylglutaryl CoA reductase I (HMGR1) genes, which are involved in chlorogenic acid and steroidal glycoalkaloid biosynthesis, respectively, also increased in response to tuber herbivory. Leaf metabolite profiling demonstrated the accumulation of unknown metabolites as well as the known potato defense compounds chlorogenic acid, α-solanine, and α-chaconine. When added to insect diet at concentrations similar to those found in potato leaves, chlorogenic acid, α-solanine, and α-chaconine all reduced S. exigua larval growth. Thus, despite the fact that tubers are a metabolic sink tissue, T. solanivora feeding elicits a systemic signal that induces aboveground resistance against S. exigua and S. frugiperda by increasing foliar abundance of defensive metabolites.

  4. Impact of climate and vegetation type on evapotranspiration from green roofs

    NASA Astrophysics Data System (ADS)

    Sia, M. E.; Robinson, C. E.; O'Carroll, D. M.; Voogt, J. A.; Smart, C. C.; Way, D. A.

    2015-12-01

    Green roofs are an increasingly popular low impact development tool used to mitigate the adverse effects of urbanization and the loss of vegetated spaces. The benefits of green roofs include reducing stormwater volume and peak flows, reducing building energy loads, and mitigating the urban heat island effect. Evapotranspiration (ET) is a key process fundamental to hydrologic and thermal performance of green roofs. For example, ET governs the water storage volume available in the soil medium and thus the ability of the green roof to retain and attenuate stormwater. Green roof design considerations such as soil medium depth and plant type impact ET rates. Additionally, climate has a strong impact on ET rates. To date, the influence between climate and green roof design factors (e.g. vegetation type and soil medium depth) on ET rates have not been well quantified. We performed a field study to evaluate the impact of climate, vegetation type, and soil medium depth on ET rates from extensive modular green roofs over prolonged drying periods. Three Canadian cities with distinct climates were chosen as field sites: London, ON, Calgary, AB, and Halifax, NS. At each site, daily module weights were recorded from May to August in 2013 and 2014 for approximately 40 green roof modules. These modules were divided into four vegetation treatments (three single species and one mixed species), and each treatment was divided into two groups of soil medium depth (10 cm or 15 cm). Daily ET rates and seasonal moisture loss were calculated and compared for the modules to determine which treatment provided the highest ET rates. The root depth profile, leaf area index, and stomatal resistance were also measured. On average, daily ET rates among the vegetation treatments did not vary greatly, however, observations on plant survival indicate which plant types are best suited for each site. In all three sites, mixed species in 15 cm of soil medium had higher seasonal moisture loss compared to

  5. Estimating above-ground biomasss using lidar remote sensing

    NASA Astrophysics Data System (ADS)

    Lim, Kevin S.; Treitz, Paul; Morrison, Ian; Baldwin, Ken

    2003-03-01

    Previous forest research using time-of-flight lidar suggests that there exists some quantile of the distribution of laser canopy heights that could provide an estimate of various forest biophysical properties. The results presented here not only support this theory, but also extend it by suggesting that a quantile of the distribution of all laser heights could provide estimates of aboveground biomass for forests with similar stand structure. Tolerant northern hardwood forests, composed predominantly of mature sugar maple (Acer saccharum Marsh.) and yellow birch (Betula alleghaniensis Britton), were surveyed using an ALTM 1225 (Optech Inc.) in August 2000. Field data for 49 circular plots, each 400 m2 in area, were collected in July 2000. Using site-specific allometric equations, total aboveground biomass and biomass components (i.e., stem wood, stem bark, live branches, and foliage) were derived for each plot. Three laser height metrics were derived from the lidar data: (i) maximum laser height; (ii) mean laser height; and (iii) mean laser height calculated from lidar returns filtered based on a threshold applied to the intensity return data LhIR). LhIR was identified as the best predictor of total aboveground biomass (R2 = 0.85) and biomass components (R2 between 0.84 to 0.85) when all plot types were considered.

  6. Using soil microbial inoculations to enhance substrate performance on extensive green roofs.

    PubMed

    Molineux, Chloe J; Gange, Alan C; Newport, Darryl J

    2017-02-15

    Green roofs are increasing in popularity in the urban environment for their contribution to green infrastructure; but their role for biodiversity is not often a design priority. Maximising biodiversity will impact positively on ecosystem services and is therefore fundamental for achieving the greatest benefits from green roofs. Extensive green roofs are lightweight systems generally constructed with a specialised growing medium that tends to be biologically limited and as such can be a harsh habitat for plants to thrive in. Thus, this investigation aimed to enhance the soil functioning with inoculations of soil microbes to increase plant diversity, improve vegetation health/performance and maximise access to soil nutrients. Manipulations included the addition of mycorrhizal fungi and a microbial mixture ('compost tea') to green roof rootzones, composed mainly of crushed brick or crushed concrete. The study revealed that growing media type and depth play a vital role in the microbial ecology of green roofs, with complex relationships between depth and type of substrate and the type of microbial inoculant applied, with no clear pattern being observed. For bait plant measurements (heights, leaf numbers, root/shoot biomass, leaf nutrients), a compost tea may have positive effects on plant performance when grown in substrates of shallower depths (5.5cm), even one year after inoculums are applied. Results from the species richness surveys show that diversity was significantly increased with the application of an AM fungal treatment and that overall, results suggest that brick-based substrate blends are most effective for vegetation performance as are deeper depths (although this varied with time). Microbial inoculations of green roof habitats appeared to be sustainable; they need only be done once for benefits to still been seen in subsequent years where treatments are added independently (not in combination). They seem to be a novel and viable method of enhancing

  7. The hydrological behaviour of extensive and intensive green roofs in a dry climate.

    PubMed

    Razzaghmanesh, M; Beecham, S

    2014-11-15

    This paper presents the results of a hydrological investigation of four medium scale green roofs that were set up at the University of South Australia. In this study, the potential of green roofs as a source control device was investigated over a 2 year period using four medium size green roof beds comprised of two growth media types and two media depths. During the term of this study, 226 rainfall events were recorded and these were representative of the Adelaide climate. In general, there were no statistically significant differences between the rainfall and runoff parameters for the intensive and extensive beds except for peak attenuation and peak runoff delay, for which higher values were recorded in the intensive beds. Longer dry periods generally resulted in higher retention coefficients and higher retention was also recorded in warmer seasons. The average retention coefficient for intensive systems (89%) was higher than for extensive systems (74%). It was shown that rainfall depth, intensity, duration and also average dry weather period between events can change the retention performance and runoff volume of the green roofs. Comparison of green and simulated conventional roofs indicated that the former were able to mitigate the peak of runoff and could delay the start of runoff. These characteristics are important for most source control measures. The recorded rainfall and runoff data displayed a non-linear relationship. Also, the results indicated that continuous time series modelling would be a more appropriate technique than using peak rainfall intensity methods for green roof design and simulation. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. PERFORMANCE OF AN EARTHQUAKE EXCITED ROOF DIAPHRAGM.

    USGS Publications Warehouse

    Celebi, M.; Brady, G.; Safak, E.; Converse, A.; ,

    1986-01-01

    The objective of this paper is to study the earthquake performance of the roof diaphragm of the West Valley College gymnasium in Saratoga, California through a complete set of acceleration records obtained during the 24 April 1984 Morgan Hill Earthquake (M equals 6. 1). The roof diaphragm of the 112 ft. multiplied by 144 ft. rectangular, symmetric gymnasium consists of 3/8 in. plywood over tongue-and-groove sheathing attached to steel trusses supported by reinforced concrete columns and walls. Three sensors placed in the direction of each of the axes of the diaphragm facilitate the evaluation of in-plane deformation of the diaphragm. Other sensors placed at ground level measure vertical and horizontal motion of the building floor, and consequently allow the calculation of the relative motion of the diaphragm with respect to the ground level.

  9. Demonstration of energy savings of cool roofs. Executive summary

    SciTech Connect

    Konopacki, S.; Gartland, L.; Akbari, H.; Rainer, L.

    1998-06-01

    The use of dark roofs affects cooling and heating energy use in buildings and the urban climate. At the building scale, dark roofs are heated by the summer sun and thus raise the summertime air-conditioning (a/c) demand. For highly-absorptive (low-albedo) roofs the difference between the surface and ambient air temperatures may be as high as 90 F on a summer afternoon. While for less absorptive (high-albedo) surfaces with similar insulative properties, such as roofs covered with a white coating, the difference is only about 20 F. For this reason, cool roofs (which absorb little insolation) can be effective in reducing cooling energy use. Earlier studies have suggested that cool roofs incur no additional cost if color changes are incorporated into routine re-roofing and re-surfacing schedules. There is a sizable body of measured data (primarily collected for residential sector) documenting energy-saving effects of cool roofs as shown. Both measured data and simulations clearly demonstrate that increasing the albedo of roofs is an attractive (and cost-effective) way of reducing the net radiative heat gains through the roof and hence, reducing building cooling loads. To change the albedo, the rooftops of buildings may be painted with reflective coatings or covered with a new light-colored material. Since most roofs have regular maintenance schedules or need to be re-roofed or re-coated periodically, the change of the albedo should be done then. In that case, the cost would be limited to the incremental cost associated with the high-albedo material. In buildings and climates with significant air-conditioning use, increasing the albedo of roofs will reduce energy use and produce a stream of savings immediately.

  10. Thermal Conductivity of Weathered Polyurethane Foam Roofing.

    DTIC Science & Technology

    1982-09-01

    Experimental polyurethane foam roofing systems, by J. R. Keeton , R. L. Alumbaugh, Ph.D , and E. F. Humm. Port Hueneme, Calif., Aug 1976. 2. . Purchase...101. Pearl Harbor, HI; CODE 09P PEARL HARBOR HI: Code 2011 Pearl Harbor. HI; Code 402. RDT&E. Pearl Harbor HI; Commander. Pearl Harbor. HI: Library...Code 2011 San Bruno, CA NAVFACENGCOM CONTRACTS AROICC MCAS El Toro; AROICC, NAVSTA Brooklyn, NY; AROICC, Point Mugu CA; AROICC, Quantico, VA; Colts

  11. Installation of a Roof Mounted Photovoltaic System

    NASA Astrophysics Data System (ADS)

    Lam, M.

    2015-12-01

    In order to create a safe and comfortable environment for students to learn, a lot of electricity, which is generated from coal fired power plants, is used. Therefore, ISF Academy, a school in Hong Kong with approximately 1,500 students, will be installing a rooftop photovoltaic (PV) system with 302 solar panels. Not only will these panels be used to power a classroom, they will also serve as an educational opportunity for students to learn about the importance of renewable energy technology and its uses. There were four different options for the installation of the solar panels, and the final choice was made based on the loading capacity of the roof, considering the fact that overstressing the roof could prove to be a safety hazard. Moreover, due to consideration of the risk of typhoons in Hong Kong, the solar panel PV system will include concrete plinths as counterweights - but not so much that the roof would be severely overstressed. During and after the installation of the PV system, students involved would be able to do multiple calculations, such as determining the reduction of the school's carbon footprint. This can allow students to learn about the impact renewable energy can have on the environment. Another project students can participate in includes measuring the efficiency of the solar panels and how much power can be produced per year, which in turn can help with calculate the amount of money saved per year and when we will achieve economic parity. In short, the installation of the roof mounted PV system will not only be able to help save money for the school but also provide learning opportunities for students studying at the ISF Academy.

  12. Thrust bolting: Roof-bolt-support apparatus

    SciTech Connect

    Tadolini, S.C.; Dolinar, D.R.

    1991-01-01

    The invention relates to a method for installing a roof bolt in a borehole of a rock formation and more specifically to tensioning the unit without the aid of a mechanical anchoring device or threaded tensioning threads. The bolt is capable of being placed into tension along the length and the levels of active support can be controlled by varying the length of the grouted portion and the level of thrust applied to the bolt during installation.

  13. Experimental Polyurethane Foam Roof Systems - II.

    DTIC Science & Technology

    1983-01-01

    reflect the effects of cloud cover, windspeed, and radiation from the roof during early morning and late evening hours. Measurement of the area under the...INN \\k I, N’. tlir’I’iii V A I \\’A SIurelS42r. K110i tlIe. I ct Ili Solair i imip .\\r nill. Kiw\\\\, tMe. I N I C(I’ 0)1,4 (IC, Ni’rtolk. \\.A ( ( I

  14. Final Technical Report for CENTRIA's EnergyPeak Building Integrated Photovoltaics ( BIPV ) for Standing Seam Metal Roofing Project (DE-FG36-08GO88131)

    SciTech Connect

    Mowrey, Rick

    2010-07-31

    Architects have said they will adopt Solar Roofs when they are integrated into roofing systems, building design, plans and specifications, and bidding procedures . Standing Seam Metal Roof manufacturers will answer these architects needs if someone will establish standards, pre-design systems, write specifications, tests systems, meet codes, etc. Energypeak was developed to provide the above so Architects can specify BIPV Standing Seam Roof Systems and Manufacturers can brand, market, sell, manufacture and deliver these systems. EnergyPeak took on the challenge to design BIPV modules using current PV technology, design electrical components, develop wire management systems, test, meet codes, write cad drawings and specifications, commercialize and deliver complete standards to the Industry.

  15. Aging and weathering of cool roofing membranes

    SciTech Connect

    Akbari, Hashem; Berhe, Asmeret A.; Levinson, Ronnen; Graveline,Stanley; Foley, Kevin; Delgado, Ana H.; Paroli, Ralph M.

    2005-08-23

    Aging and weathering can reduce the solar reflectance of cool roofing materials. This paper summarizes laboratory measurements of the solar spectral reflectance of unweathered, weathered, and cleaned samples collected from single-ply roofing membranes at various sites across the United States. Fifteen samples were examined in each of the following six conditions: unweathered; weathered; weathered and brushed; weathered, brushed and then rinsed with water; weathered, brushed, rinsed with water, and then washed with soap and water; and weathered, brushed, rinsed with water, washed with soap and water, and then washed with an algaecide. Another 25 samples from 25 roofs across the United States and Canada were measured in their unweathered state, weathered, and weathered and wiped. We document reduction in reflectivity resulted from various soiling mechanisms and provide data on the effectiveness of various cleaning approaches. Results indicate that although the majority of samples after being washed with detergent could be brought to within 90% of their unweathered reflectivity, in some instances an algaecide was required to restore this level of reflectivity.

  16. Floating roof tank with rim space seal

    SciTech Connect

    Grove, R.B.; Peters, S.W.; Tellalian, M.L.

    1986-10-07

    This patent describes a vertical cylindrical liquid storage tank having a circular floating roof of smaller diameter than the tank thereby defining a clearance space between the roof edge and the tank wall; a seal joined to the roof and extending upwardly therefrom into slidable contact with the tank wall; the seal completely covering the clearance space; the seal comprising a plurality of individual flexible sections of sheet material in substantially side-by-side arrangement but with adjacent section side edge portions overlapping each other; a gasket between the overlapping side edge portions; a clip attached to each section adjacent its edge portion which is overlapped by the edge portion of an adjacent section; the clip having a wing spaced upward from the section to which it is attached and extending over the edge portion of the adjacent section to press the edge portions together, but permit the edge portions to slide laterally with respect to each other; and a flexible elastometric tip joined to the outer end of the sections and in slidable contact with the tank wall.

  17. Results for the Aboveground Configuration of the Boiling Water Reactor Dry Cask Simulator

    SciTech Connect

    Durbin, Samuel G.; Lindgren, Eric R.

    2016-09-30

    The thermal performance of commercial nuclear spent fuel dry storage casks is evaluated through detailed numerical analysis. These modeling efforts are completed by the vendor to demonstrate performance and regulatory compliance. The calculations are then independently verified by the Nuclear Regulatory Commission (NRC). Carefully measured data sets generated from testing of full sized casks or smaller cask analogs are widely recognized as vital for validating these models. Recent advances in dry storage cask designs have significantly increased the maximum thermal load allowed in a cask in part by increasing the efficiency of internal conduction pathways and also by increasing the internal convection through greater canister helium pressure. These same canistered cask systems rely on ventilation between the canister and the overpack to convect heat away from the canister to the environment for both above and belowground configurations. While several testing programs have been previously conducted, these earlier validation attempts did not capture the effects of elevated helium pressures or accurately portray the external convection of aboveground and belowground canistered dry cask systems. The purpose of the current investigation was to produce data sets that can be used to test the validity of the assumptions associated with the calculations used to determine steady-state cladding temperatures in modern dry casks that utilize elevated helium pressure in the sealed canister in an aboveground configuration.

  18. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2005-01-15

    In this quarter, the field, theoretical and programming works have been performed toward achieving the research goals set in the proposal. The main accomplishments in this quarter included: (1) one more field test has been conducted in an underground coal mine, (2) optimization studies of the control parameters have been conducted, (3) method to use torque to thrust ratio as indicator of rock relative hardness has also been explored, and (4) about 98% of the development work for the roof geology mapping program, MRGIS, has completed, (5) A real time roof geology mapping system for roof bolters in limestone mine, including a special version of the geology mapping program and hardware, has already been verified to perform very well in underground production condition.

  19. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or... roof, face or ribs and coal or rock bursts. (b) No person shall work or travel under unsupported roof...

  20. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or... roof, face or ribs and coal or rock bursts. (b) No person shall work or travel under unsupported roof...

  1. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or... roof, face or ribs and coal or rock bursts. (b) No person shall work or travel under unsupported roof...

  2. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or... roof, face or ribs and coal or rock bursts. (b) No person shall work or travel under unsupported roof...

  3. Development of a roof bolter canopy air curtain for respirable dust control

    PubMed Central

    Reed, W.R.; Joy, G.J.; Kendall, B.; Bailey, A.; Zheng, Y.

    2017-01-01

    Testing of the roof bolter canopy air curtain (CAC) designed by the U.S. National Institute for Occupational Safety and Health (NIOSH) has gone through many iterations, demonstrating successful dust control performance under controlled laboratory conditions. J.H. Fletcher & Co., an original equipment manufacturer of mining equipment, further developed the concept by incorporating it into the design of its roof bolting machines. In the present work, laboratory testing was conducted, showing dust control efficiencies ranging from 17.2 to 24.5 percent. Subsequent computational fluid dynamics (CFD) analysis revealed limitations in the design, and a potential improvement was analyzed and recommended. As a result, a new CAC design is being developed, incorporating the results of the testing and CFD analysis.

  4. Relationship of roof rat population indices with damage to sugarcane

    USGS Publications Warehouse

    Lefebvre, Lynn W.; Engeman, Richard M.; Decker, David G.; Holler, Nicholas R.

    1989-01-01

    Roof rats (Rattus rattus) cause substantial damage to sugarcane in South Florida (Samol 1972; Lefebvre et al. 1978, 1985). Accurate estimates of roof rat populations in sugarcane fields would be useful for determining when to to treat a field to control roof rats and for assessing the efficacy of control. However, previous studies have indicated that roof rats exhibit trap shyness, which makes capture-recapture population estimates difficult (Lefebvre et al. 1978, 1985; Holler et al., 1981). Until trapping methods are sufficiently improved to allow accurate population estimates, indices of population size that relate to damage need to be developed. The objectives of our study were to examine the relationship of several indices of roof rat populations to the percentage of sugarcane stalks damaged at harvest; to determine which population index would be most useful for sugarcane growers; and to report on a test of several types of live traps for roof rats.

  5. Cool roofs as an energy conservation measure for federal buildings

    SciTech Connect

    Taha, Haider; Akbari, Hashem

    2003-04-07

    We have developed initial estimates of the potential benefits of cool roofs on federal buildings and facilities (building scale) as well as extrapolated the results to all national facilities under the administration of the Federal Energy Management Program (FEMP). In addition, a spreadsheet ''calculator'' is devised to help FEMP estimate potential energy and cost savings of cool roof projects. Based on calculations for an average insulation level of R-11 for roofs, it is estimated that nationwide annual savings in energy costs will amount to $16M and $32M for two scenarios of increased roof albedo (moderate and high increases), respectively. These savings, corresponding to about 3.8 percent and 7.5 percent of the base energy costs for FEMP facilities, include the increased heating energy use (penalties) in winter. To keep the cost of conserved energy (CCE) under $0.08 kWh-1 as a nationwide average, the calculations suggest that the incremental cost for cool roofs should not exceed $0.06 ft-2, assuming that cool roofs have the same life span as their non-cool counterparts. However, cool roofs usually have extended life spans, e.g., 15-30 years versus 10 years for conventional roofs, and if the costs of re-roofing are also factored in, the cutoff incremental cost to keep CCE under $0.08 kWh-1 can be much higher. In between these two ends, there is of course a range of various combinations and options.

  6. Interior Cornice Profile, Interior Pilaster Profile, Lions Head Roof Scupper, ...

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

    Interior Cornice Profile, Interior Pilaster Profile, Lions Head Roof Scupper, and Interior Panel Moulding - Flanders Field American Cemetery & Memorial, Chapel, Wortegemseweg 117, Waregem, West Flanders (Belgium)

  7. 5. VIEW OF VENTILATION HOUSES AND ROOF MONITOR FROM SOUTHEAST ...

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

    5. VIEW OF VENTILATION HOUSES AND ROOF MONITOR FROM SOUTHEAST CORNER OF ROOF. ROOF MONITOR WINDOWS HAVE BEEN INFILLED WITH BRICK. THE VENTILATION HOUSES ARE PART OF THE ORIGINAL CENTRAL AIR CONDITIONING SYSTEM AND CONTAINED AIR WASHERS, FANS AND OTHER HUMIDFYING EQUIPMENT FROM PARKS-CRAMER COMPANY OF FITCHBURG, MASSACHUSETTS. LOCATING THIS EQUIPMENT ON THE ROOF MADE IT UNNECESSARY TO CONSTRUCT A FULL BASEMENT, AND THEREFORE LOWERED CONSTRUCTION COSTS. THIS ARRANGEMENT ALSO PUT THE AIR CONDITIONING EQUIPMENT CLOSEST TO THE TOP FLOOR SPINNING ROOM, WHICH HAD THE GREATEST COOLING REQUIREMENTS. - Stark Mill, 117 Corinth Road, Hogansville, Troup County, GA

  8. 71. Joe Moore, Photographer. September, 1996. BEVATRON ROOF SHIELDING AND ...

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

    71. Joe Moore, Photographer. September, 1996. BEVATRON ROOF SHIELDING AND BUILDING TRUSS STRUCTURE - University of California Radiation Laboratory, Bevatron, 1 Cyclotron Road, Berkeley, Alameda County, CA

  9. Cool Roof Systems; What is the Condensation Risk?

    SciTech Connect

    Kehrer, Manfred; Pallin, Simon B

    2014-01-01

    A white roof, or cool roof, is constructed to decrease thermal loads from solar radiation, therefore saving energy by decreasing the cooling demands. Unfortunately, cool roofs with a mechanically attached membrane have shown a higher risk of intermediate condensation in the materials below the membrane in certain climates (Ennis & Kehrer, 2011) and in comparison with similar constructions with a darker exterior surface (Bludau, Zirkelbach, & Kuenzel, 2009). As a consequence, questions have been raised regarding the sustainability and reliability of using cool roof membranes in northern U.S. climate zones.

  10. 43. TOP OF SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING ...

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

    43. TOP OF SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING EAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  11. 36. FLAG TOWER CLOCK ZONE FROM SOUTH TOWER ROOF, LOOKING ...

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

    36. FLAG TOWER CLOCK ZONE FROM SOUTH TOWER ROOF, LOOKING NORTH - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  12. 39. CLOSER VIEW OF CAMPANILE FROM SOUTH TOWER ROOF, LOOKING ...

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

    39. CLOSER VIEW OF CAMPANILE FROM SOUTH TOWER ROOF, LOOKING NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  13. 44. ARTS AND INDUSTRIES BUILDING FROM SOUTH TOWER ROOF, LOOKING ...

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

    44. ARTS AND INDUSTRIES BUILDING FROM SOUTH TOWER ROOF, LOOKING SOUTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  14. 37. NORTH TOWER UPPER ZONE FROM SOUTH TOWER ROOF, LOOKING ...

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

    37. NORTH TOWER UPPER ZONE FROM SOUTH TOWER ROOF, LOOKING NORTH - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  15. 47. NORTHWEST TOWER FROM SOUTH TOWER ROOF, LOOKING NORTH BY ...

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

    47. NORTHWEST TOWER FROM SOUTH TOWER ROOF, LOOKING NORTH BY NORTHWEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  16. 40. CAMPANILE & SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING ...

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

    40. CAMPANILE & SOUTHEAST TOWER FROM SOUTH TOWER ROOF, LOOKING EAST BY NORTHEAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  17. Air-quality implications of widespread adoption of cool roofs on ozone and particulate matter in southern California.

    PubMed

    Epstein, Scott A; Lee, Sang-Mi; Katzenstein, Aaron S; Carreras-Sospedra, Marc; Zhang, Xinqiu; Farina, Salvatore C; Vahmani, Pouya; Fine, Philip M; Ban-Weiss, George

    2017-08-22

    The installation of roofing materials with increased solar reflectance (i.e., "cool roofs") can mitigate the urban heat island effect and reduce energy use. In addition, meteorological changes, along with the possibility of enhanced UV reflection from these surfaces, can have complex impacts on ozone and PM2.5 concentrations. We aim to evaluate the air-quality impacts of widespread cool-roof installations prescribed by California's Title 24 building energy efficiency standards within the heavily populated and polluted South Coast Air Basin (SoCAB). Development of a comprehensive rooftop area database and evaluation of spectral reflectance measurements of roofing materials allows us to project potential future changes in solar and UV reflectance for simulations using the Weather Research Forecast and Community Multiscale Air Quality (CMAQ) models. 2012 meteorological simulations indicate a decrease in daily maximum temperatures, daily maximum boundary layer heights, and ventilation coefficients throughout the SoCAB upon widespread installation of cool roofs. CMAQ simulations show significant increases in PM2.5 concentrations and policy-relevant design values. Changes in 8-h ozone concentrations depend on the potential change in UV reflectance, ranging from a decrease in population-weighted concentrations when UV reflectance remains unchanged to an increase when changes in UV reflectance are at an upper bound. However, 8-h policy-relevant ozone design values increase in all cases. Although the other benefits of cool roofs could outweigh small air-quality penalties, UV reflectance standards for cool roofing materials could mitigate these negative consequences. Results of this study motivate the careful consideration of future rooftop and pavement solar reflectance modification policies.

  18. Corrosion fundamentals and corrosion effects on aboveground storage tanks

    SciTech Connect

    Fitzgerald, J.H. III

    1995-12-31

    Corrosion is an electrochemical process that involves ion migration and electron flow. The electrochemical process is explained and the four elements of the basic cell are described--anode, cathode, electrolyte and return circuit. The corrosion mechanisms affecting underground structures can be divided into two main categories--naturally occurring corrosion and stray current corrosion. Several examples of each are shown. These mechanisms of corrosion are applicable to aboveground storage tanks. Various types of exterior and interior corrosion of ASTs are explained in the light of electrochemical theory.

  19. Structure, Aboveground Biomass, and Soil Characterization of Avicennia marina in Eastern Mangrove Lagoon National Park, Abu Dhabi

    NASA Astrophysics Data System (ADS)

    Alsumaiti, Tareefa Saad Sultan

    Mangrove forests are national treasures of the United Arab Emirates (UAE) and other arid countries with limited forested areas. Mangroves form a crucial part of the coastal ecosystem and provide numerous benefits to society, economy, and especially the environment. Mangrove trees, specifically Avicennia marina, are studied in their native habitat in order to characterize their population structure, aboveground biomass, and soil properties. This study focused on Eastern Mangrove Lagoon National Park in Abu Dhabi, which was the first mangrove protected area to be designated in UAE. In situ measurements were collected to estimate Avicennia marina status, mortality rate (%), height (m), crown spread (m), stem number, diameter at breast height (cm), basal area (m), and aboveground biomass (t ha-1 ). Small-footprint aerial light detection and ranging (LIDAR) data acquired by UAE were processed to characterize mangrove canopy height and aboveground biomass density. This included extraction of LIDAR-derived height percentile statistics, segmentation of the forest into structurally homogenous units, and development of regression relationships between in situ reference and remote sensing data using a machine learning approach. An in situ soil survey was conducted to examine the soils' physical and chemical properties, fertility status, and organic matter. The data of soil survey were used to create soil maps to evaluate key characteristics of soils, and their influence on Avicennia marina in Eastern Mangrove Lagoon National Park. The results of this study provide new insights into Avicennia marina canopy population, structure, aboveground biomass, and soil properties in Abu Dhabi, as data in such arid environments is lacking. This valuable information can help in managing and preserving this unique ecosystem.

  20. Closure Report for Corrective Action Unit 134: Aboveground Storage Tanks, Nevada Test Site, Nevada

    SciTech Connect

    NSTec Environmental Restoration

    2009-06-30

    Corrective Action Unit (CAU) 134 is identified in the Federal Facility Agreement and Consent Order (FFACO) as “Aboveground Storage Tanks” and consists of the following four Corrective Action Sites (CASs), located in Areas 3, 15, and 29 of the Nevada Test Site: · CAS 03-01-03, Aboveground Storage Tank · CAS 03-01-04, Tank · CAS 15-01-05, Aboveground Storage Tank · CAS 29-01-01, Hydrocarbon Stain

  1. A graph edit dictionary for correcting errors in roof topology graphs reconstructed from point clouds

    NASA Astrophysics Data System (ADS)

    Xiong, B.; Oude Elberink, S.; Vosselman, G.

    2014-07-01

    In the task of 3D building model reconstruction from point clouds we face the problem of recovering a roof topology graph in the presence of noise, small roof faces and low point densities. Errors in roof topology graphs will seriously affect the final modelling results. The aim of this research is to automatically correct these errors. We define the graph correction as a graph-to-graph problem, similar to the spelling correction problem (also called the string-to-string problem). The graph correction is more complex than string correction, as the graphs are 2D while strings are only 1D. We design a strategy based on a dictionary of graph edit operations to automatically identify and correct the errors in the input graph. For each type of error the graph edit dictionary stores a representative erroneous subgraph as well as the corrected version. As an erroneous roof topology graph may contain several errors, a heuristic search is applied to find the optimum sequence of graph edits to correct the errors one by one. The graph edit dictionary can be expanded to include entries needed to cope with errors that were previously not encountered. Experiments show that the dictionary with only fifteen entries already properly corrects one quarter of erroneous graphs in about 4500 buildings, and even half of the erroneous graphs in one test area, achieving as high as a 95% acceptance rate of the reconstructed models.

  2. Modelling runoff on ceramic tile roofs using the kinematic wave equations

    NASA Astrophysics Data System (ADS)

    Silveira, Alexandre; Abrantes, João; de Lima, João; Lira, Lincoln

    2016-04-01

    Rainwater harvesting is a water saving alternative strategy that presents many advantages and can provide solutions to address major water resources problems, such as fresh water scarcity, urban stream degradation and flooding. In recent years, these problems have become global challenges, due to climatic change, population growth and increasing urbanisation. Generally, roofs are the first to come into contact with rainwater; thus, they are the best candidates for rainwater harvesting. In this context, the correct evaluation of roof runoff quantity and quality is essential to effectively design rainwater harvesting systems. Despite this, many studies usually focus on the qualitative aspects in detriment of the quantitative aspects. Laboratory studies using rainfall simulators have been widely used to investigate rainfall-runoff processes. These studies enabled a detailed exploration and systematic replication of a large range of hydrologic conditions, such as rainfall spatial and temporal characteristics, providing for a fast way to obtain precise and consistent data that can be used to calibrate and validate numerical models. This study aims to evaluate the performance of a kinematic wave based numerical model in simulating runoff on sloping roofs, by comparing the numerical results with the ones obtained from laboratory rainfall simulations on a real-scale ceramic tile roof (Lusa tiles). For all studied slopes, simulated discharge hydrographs had a good adjust to observed ones. Coefficient of determination and Nash-Sutcliffe efficiency values were close to 1.0. Particularly, peak discharges, times to peak and peak durations were very well simulated.

  3. Linkages between below and aboveground communities: Decomposer responses to simulated tree species loss are largely additive.

    Treesearch

    Becky A. Ball; Mark A. Bradford; Dave C. Coleman; Mark D. Hunter

    2009-01-01

    Inputs of aboveground plant litter influence the abundance and activities of belowground decomposer biota. Litter-mixing studies have examined whether the diversity and heterogeneity of litter inputs...

  4. Estimating Heat and Mass Transfer Processes in Green Roof Systems: Current Modeling Capabilities and Limitations (Presentation)

    SciTech Connect

    Tabares Velasco, P. C.

    2011-04-01

    This presentation discusses estimating heat and mass transfer processes in green roof systems: current modeling capabilities and limitations. Green roofs are 'specialized roofing systems that support vegetation growth on rooftops.'

  5. 40 CFR 427.60 - Applicability; description of the asbestos roofing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asbestos roofing subcategory. 427.60 Section 427.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Roofing Subcategory § 427.60 Applicability; description of the asbestos roofing subcategory....

  6. TASK 2.5.7 FIELD EXPERIMENTS TO EVALUATE COOL-COLORED ROOFING

    SciTech Connect

    Miller, William A; Cherry, Nigel J; Allen, Richard Lowell; Childs, Phillip W; Atchley, Jerald Allen; Ronnen, Levinson; Akbari, Hashem; Berhahl, Paul

    2010-03-01

    counter battens, providing a nailing surface for the concrete tile. This double batten construction forms an inclined air channel running from the soffit to the ridge. The bottom surface of the channel is formed by the roof decking and is relatively flat and smooth. The top surface is created by the underside of the roofing tiles, and is designed to be an air permeable covering to alleviate the underside air pressure and minimize wind uplift on the tiles. The resulting air flows also have a cooling influence which further complicates prediction of the heat penetrating through the deck because an accurate measure of the airflow is required to predict the heat transfer. Measured temperatures and heat flows at the roof surface, within the attic and at the ceiling of the houses are discussed as well as the power usage to help gauge the benefit of cool-pigmented reflective roof products fitted with and without ventilation above the roof deck. Ventilation occurring above the deck is an inherent feature for tile roof assemblies, and is formed by an air space between the exterior face of the roof sheathing and the underside of the tile. The greater the tile s profile the greater is the effect of the ventilation which herein is termed above-sheathing ventilation (ASV). However, because of the complexity of the thermally induced flow, little credit is allowed by state and federal building codes. ASHRAE (2005) provides empirical data for the effective thermal resistance of plane air spaces. A -in. (0.0191-m) plane air space inclined at 45 with the horizontal has an RUS-0.85 (RSI-0.15) . Our intent is to help further deploy cool color pigments in roofs by conducting field experiments to evaluate the new cool-colored roofing materials in the hot climate of Southern California. The collected data will be used to showcase and market the performance of new cool-roof products and also to help formulate and validate computer codes capable of calculating the heat transfer occurring within

  7. Aboveground insect infestation attenuates belowground Agrobacterium-mediated genetic transformation.

    PubMed

    Song, Geun Cheol; Lee, Soohyun; Hong, Jaehwa; Choi, Hye Kyung; Hong, Gun Hyong; Bae, Dong-Won; Mysore, Kirankumar S; Park, Yong-Soon; Ryu, Choong-Min

    2015-07-01

    Agrobacterium tumefaciens causes crown gall disease. Although Agrobacterium can be popularly used for genetic engineering, the influence of aboveground insect infestation on Agrobacterium induced gall formation has not been investigated. Nicotiana benthamiana leaves were exposed to a sucking insect (whitefly) infestation and benzothiadiazole (BTH) for 7 d, and these exposed plants were inoculated with a tumorigenic Agrobacterium strain. We evaluated, both in planta and in vitro, how whitefly infestation affects crown gall disease. Whitefly-infested plants exhibited at least a two-fold reduction in gall formation on both stem and crown root. Silencing of isochorismate synthase 1 (ICS1), required for salicylic acid (SA) synthesis, compromised gall formation indicating an involvement of SA in whitefly-derived plant defence against Agrobacterium. Endogenous SA content was augmented in whitefly-infested plants upon Agrobacterium inoculation. In addition, SA concentration was three times higher in root exudates from whitefly-infested plants. As a consequence, Agrobacterium-mediated transformation of roots of whitefly-infested plants was clearly inhibited when compared to control plants. These results suggest that aboveground whitefly infestation elicits systemic defence responses throughout the plant. Our findings provide new insights into insect-mediated leaf-root intra-communication and a framework to understand interactions between three organisms: whitefly, N. benthamiana and Agrobacterium. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  8. Atmospheric contribution to boron enrichment in aboveground wheat tissues.

    PubMed

    Wang, Cheng; Ji, Junfeng; Chen, Mindong; Zhong, Cong; Yang, Zhongfang; Browne, Patrick

    2017-05-01

    Boron is an essential trace element for all organisms and has both beneficial and harmful biological functions. A particular amount of boron is discharged into the environment every year because of industrial activities; however, the effects of environmental boron emissions on boron accumulation in cereals has not yet been estimated. The present study characterized the accumulation of boron in wheat under different ecological conditions in the Yangtze River Delta (YRD) area. This study aimed to estimate the effects of atmospheric boron that is associated with industrial activities on boron accumulation in wheat. The results showed that the concentrations of boron in aboveground wheat tissues from the highly industrialized region were significantly higher than those from the agriculture-dominated region, even though there was no significant difference in boron content in soils. Using the model based on the translocation coefficients of boron in the soil-wheat system, we estimated that the contribution of atmosphere to boron accumulation in wheat straw in the highly industrialized region exceeded that in the agriculture-dominated region by 36%. In addition, from the environmental implication of the model, it was estimated that the development of boron-utilizing industries had elevated the concentration of boron in aboveground wheat tissues by 28-53%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Green roof and storm water management policies: monitoring experiments on the ENPC Blue Green Wave

    NASA Astrophysics Data System (ADS)

    Versini, Pierre-Antoine; Gires, Auguste; Fitton, George; Tchiguirinskaia, Ioulia; Schertzer, Daniel

    2015-04-01

    Currently widespread in new urban projects, green roofs have shown a positive impact on urban runoff at the building/parcel scale. Nevertheless, there is no specific policy promoting their implementation neither in Europe nor in France. Moreover they are not taken into account (and usually considered as an impervious area) in the sizing of a retention basin for instance. An interesting example is located in the heart of the Paris-East Cluster for Science and Technology (Champs-sur-Marne, France). Since 2013 a large (1 ha) wavy-form vegetated roof (called bleu green wave) is implemented. Green roof area and impervious areas are connected to a large retention basin, which has been oversized. The blue green wave represents a pioneering site where an initially amenity (decorative) design project has been transformed into a research oriented one. Several measurement campaigns have been conducted to investigate and better understand the hydrological behaviour of such a structure. Rainfall, humidity, wind velocity, water content and temperature have been particularly studied. The data collected are used for several purposes: (i) characterize the spatio-temporal variability of the green roof response, (ii) calibrate and validate a specific model simulating its hydrological behavior. Based on monitoring and modeling results, green roof performances will be quantified. It will be possible to estimate how they can reduce stormwater runoff and how these performances can vary in space and in time depending on green roof configuration, rainfall event characteristics and antecedent conditions. These quantified impacts will be related to regulation rules established by stormwater managers in order to connect the parcel to the sewer network. In the particular case of the building of a retention basin, the integration of green roof in the sizing of the basin will be studied. This work is funded by the European Blue Green Dream project (http://bgd.org.uk/, funded by Climate

  10. Extensive Green Roof Research Program at Colorado State University

    EPA Science Inventory

    In the high elevation, semi-arid climate of Colorado, green roofs have not been scientifically tested. This research examined alternative plant species, media blends, and plant interactions on an existing modular extensive green roof in Denver, Colorado. Six plant species were ev...

  11. ROOF, Taken looking southeast from the southeast corner of the ...

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

    ROOF, Taken looking southeast from the southeast corner of the stair tower roof, showing external piping and west facade of Penthouse 201P. The large stack is seen behind the Penthouse - Department of Energy, Mound Facility, Hydrolysis House Building (HH Building), One Mound Road, Miamisburg, Montgomery County, OH

  12. 1. OVERVIEW OF BUILDING 105 SHOWING LOCAL SETTING. ROOF, NORTH ...

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

    1. OVERVIEW OF BUILDING 105 SHOWING LOCAL SETTING. ROOF, NORTH END, AND WEST SIDE OF BUILDING 105 ARE VISIBLE AT LEFT PHOTO CENTER BEHIND UTILITY POLE. ROOF AND WEST END OF BUILDING 110 ARE VISIBLE AT PHOTO RIGHT BEHIND TREES. VIEW TO SOUTH FROM STREET ABOVE HOUSES. - Big Creek Hydroelectric System, Powerhouse 8, Operator Cottage, Big Creek, Big Creek, Fresno County, CA

  13. What You Should Know about Single-Ply Roofing.

    ERIC Educational Resources Information Center

    Szcygiel, Tony L.

    1998-01-01

    Explains why a single-ply roofing system is the best choice for educational facilities. It discusses how single-ply roofing systems offer flexibility with ease of application; cause less disruption during installation; and are clean, safe, and energy efficient. (GR)

  14. Fourier analysis of conductive heat transfer for glazed roofing materials

    NASA Astrophysics Data System (ADS)

    Roslan, Nurhana Lyana; Bahaman, Nurfaradila; Almanan, Raja Noorliyana Raja; Ismail, Razidah; Zakaria, Nor Zaini

    2014-07-01

    For low-rise buildings, roof is the most exposed surface to solar radiation. The main mode of heat transfer from outdoor via the roof is conduction. The rate of heat transfer and the thermal impact is dependent on the thermophysical properties of roofing materials. Thus, it is important to analyze the heat distribution for the various types of roofing materials. The objectives of this paper are to obtain the Fourier series for the conductive heat transfer for two types of glazed roofing materials, namely polycarbonate and polyfilled, and also to determine the relationship between the ambient temperature and the conductive heat transfer for these materials. Ambient and surface temperature data were collected from an empirical field investigation in the campus of Universiti Teknologi MARA Shah Alam. The roofing materials were installed on free-standing structures in natural ventilation. Since the temperature data are generally periodic, Fourier series and numerical harmonic analysis are applied. Based on the 24-point harmonic analysis, the eleventh order harmonics is found to generate an adequate Fourier series expansion for both glazed roofing materials. In addition, there exists a linear relationship between the ambient temperature and the conductive heat transfer for both glazed roofing materials. Based on the gradient of the graphs, lower heat transfer is indicated through polyfilled. Thus polyfilled would have a lower thermal impact compared to polycarbonate.

  15. Getting a Clear Focus on Roof Replacement and Management.

    ERIC Educational Resources Information Center

    Patterson, Valerie B.

    2002-01-01

    Describes how a new generation of X-ray-like vision--the patented INFRARED2k--provides roof-condition reports that help extend roof life, conserve energy, and survey for mold-supporting environments, thereby improving indoor air quality. (EV)

  16. Snow loads on roofs in areas of heavy snowfall

    Treesearch

    Robert D. Doty; Glenn H. Deitschman

    1966-01-01

    This study tested the feasibility of estimating snow loads on roofs from measurements of depth and water content of snow on nearby ground. The water content, and therefore the weight, of snow on the ground proved comparable to that of snow on roofs.

  17. Effect of roof strength in injury mitigation during pole impact.

    PubMed

    Friedman, Keith; Hutchinson, John; Mihora, Dennis; Kumar, Sri; Frieder, Russell; Sances, Anthony

    2007-01-01

    Motor vehicle accidents involving pole impacts often result in serious head and neck injuries to occupants. Pole impacts are typically associated with rollover and side collisions. During such events, the roof structure is often deformed into the occupant survival space. The existence of a strengthened roof structure would reduce roof deformation and accordingly provide better protection to occupants. The present study examines the effect of reinforced (strengthened) roofs using experimental crash study and computer model simulation. The experimental study includes the production cab structure of a pickup truck. The cab structure was loaded using an actual telephone pole under controlled laboratory conditions. The cab structure was subjected to two separate load conditions at the A-pillar and door frame. The contact force and deformation were measured using a force gauge and potentiometer, respectively. A computer finite element model was created to simulate the experimental studies. The results of finite element model matched well with experimental data during two different load conditions. The validated finite element model was then used to simulate a reinforced roof structure. The reinforced roof significantly reduced the structural deformations compared to those observed in the production roof. The peak deformation was reduced by approximately 75% and peak velocity was reduced by approximately 50%. Such a reduction in the deformation of the roof structure helps to maintain a safe occupant survival space.

  18. 14. View south from first level roof of firing pier. ...

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

    14. View south from first level roof of firing pier. Pitched corrugated metal roof marks location of the frame approach connecting the firing pier to the shop (shown in left distance). - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  19. Extensive Green Roof Research Program at Colorado State University

    EPA Science Inventory

    In the high elevation, semi-arid climate of Colorado, green roofs have not been scientifically tested. This research examined alternative plant species, media blends, and plant interactions on an existing modular extensive green roof in Denver, Colorado. Six plant species were ev...

  20. 9. Grandstand seating and aisles viewed from roof of north ...

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

    9. Grandstand seating and aisles viewed from roof of north addition of Clubhouse (roof of Chinook Pass Room). TV Center is partially visible on far left. Camera pointed N. (July 1993) - Longacres, Original Grandstand, 1621 Southwest Sixteenth Street, Renton, King County, WA

  1. 16. DETAIL OF ROOF TRUSS SYSTEM, FACING EAST, THIRD BAY ...

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

    16. DETAIL OF ROOF TRUSS SYSTEM, FACING EAST, THIRD BAY Showing bottom chords and diagonal braces of roof trusses, hoist I-beam and pulley. - U.S. Military Academy, Ice House, Mills Road at Howze Place, West Point, Orange County, NY

  2. Getting a Clear Focus on Roof Replacement and Management.

    ERIC Educational Resources Information Center

    Patterson, Valerie B.

    2002-01-01

    Describes how a new generation of X-ray-like vision--the patented INFRARED2k--provides roof-condition reports that help extend roof life, conserve energy, and survey for mold-supporting environments, thereby improving indoor air quality. (EV)

  3. What You Should Know about Single-Ply Roofing.

    ERIC Educational Resources Information Center

    Szcygiel, Tony L.

    1998-01-01

    Explains why a single-ply roofing system is the best choice for educational facilities. It discusses how single-ply roofing systems offer flexibility with ease of application; cause less disruption during installation; and are clean, safe, and energy efficient. (GR)

  4. 23. INTERIOR OF TAN 629 HANGAR, TAKEN FROM LOW ROOF, ...

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

    23. INTERIOR OF TAN 629 HANGAR, TAKEN FROM LOW ROOF, FACING NORTHEAST. SHOWS GROUND LEVEL USE OF FLOOR SPACE FOR TEMPORARY STORAGE OF CRATES. MOISTURE ON SURFACE IS FROM LEAKY HANGAR ROOF. - Idaho National Engineering Laboratory, Test Area North, Hangar No. 629, Scoville, Butte County, ID

  5. Fourier analysis of conductive heat transfer for glazed roofing materials

    SciTech Connect

    Roslan, Nurhana Lyana; Bahaman, Nurfaradila; Almanan, Raja Noorliyana Raja; Ismail, Razidah; Zakaria, Nor Zaini

    2014-07-10

    For low-rise buildings, roof is the most exposed surface to solar radiation. The main mode of heat transfer from outdoor via the roof is conduction. The rate of heat transfer and the thermal impact is dependent on the thermophysical properties of roofing materials. Thus, it is important to analyze the heat distribution for the various types of roofing materials. The objectives of this paper are to obtain the Fourier series for the conductive heat transfer for two types of glazed roofing materials, namely polycarbonate and polyfilled, and also to determine the relationship between the ambient temperature and the conductive heat transfer for these materials. Ambient and surface temperature data were collected from an empirical field investigation in the campus of Universiti Teknologi MARA Shah Alam. The roofing materials were installed on free-standing structures in natural ventilation. Since the temperature data are generally periodic, Fourier series and numerical harmonic analysis are applied. Based on the 24-point harmonic analysis, the eleventh order harmonics is found to generate an adequate Fourier series expansion for both glazed roofing materials. In addition, there exists a linear relationship between the ambient temperature and the conductive heat transfer for both glazed roofing materials. Based on the gradient of the graphs, lower heat transfer is indicated through polyfilled. Thus polyfilled would have a lower thermal impact compared to polycarbonate.

  6. Energy Star{reg{underscore}sign} label for roof products

    SciTech Connect

    Schmeltz, R.S.; Bretz, S.E.

    1998-07-01

    Home and buildings owners can save up to 40% of cooling energy costs by installing reflective roofs, especially in hot and sunny climates. The increase in exterior albedo and subsequent decrease in heat flow across the building envelope reduces the energy requirements to maintain air-conditioned space. Indirectly, the increase in overall albedo of a community as these roofs are installed in a large fraction of the buildings results in lower ambient air temperature and less need for air conditioning. Another indirect effect is a decrease in smog formation due to lower ambient air temperatures and less air pollution from power plants because of minimized electrical demand and use. The US Environmental Protection Agency and the US Department of Energy are currently developing the Energy Star Roof Products Program to create a vibrant market for energy-efficient, cost-effective roof materials through the widespread availability of products, clear recognition of the benefits by consumers, and active promotion of products by manufacturers. Several activities, including pilot procurements of room materials, and the development of outreach and training materials, will be performed to assist the transformation of the roofing market toward more energy-efficient products. Using the experiences gained in establishing the Energy Star Roof Products Program as an example, this paper will discuss the barriers to the development of energy-efficient roofing practices, program implementation, and program successes. This paper will further describe the specifics of the Energy Star Roof Products Program, its goals, benefits, activities, and timeframe.

  7. Installation, care, and maintenance of wood shake and shingle roofs

    Treesearch

    Tony Bonura; Jack Dwyer; Arnie Nebelsick; Brent Stuart; R. Sam Williams; Christopher Hunt

    2011-01-01

    This article gives general guidelines for selection, installation, finishing, and maintenance of wood shake and shingle roofs. The authors have gathered information from a variety of sources: research publications on wood finishing, technical data sheets from paint manufacturers, installation instructions for shake and shingle roofs, and interviews with experts having...

  8. Hygrothermal Performance of West Coast Wood Deck Roofing System

    SciTech Connect

    Pallin, Simon B; Kehrer, Manfred; Desjarlais, Andre Omer

    2014-02-01

    Simulations of roofing assemblies are necessary in order to understand and adequately predict actual the hygrothermal performance. At the request of GAF, simulations have been setup to verify the difference in performance between white and black roofing membrane colors in relation to critical moisture accumulation for traditional low slope wood deck roofing systems typically deployed in various western U.S. Climate Zones. The performance of these roof assemblies has been simulated in the hygrothermal calculation tool of WUFI, from which the result was evaluated based on a defined criterion for moisture safety. The criterion was defined as the maximum accepted water content for wood materials and the highest acceptable moisture accumulation rate in relation to the risk of rot. Based on the criterion, the roof assemblies were certified as being either safe, risky or assumed to fail. The roof assemblies were simulated in different western climates, with varying insulation thicknesses, two different types of wooden decking, applied with varying interior moisture load and with either a high or low solar absorptivity at the roof surface (black or white surface color). The results show that the performance of the studied roof assemblies differs with regard to all of the varying parameters, especially the climate and the indoor moisture load.

  9. QUANTIFYING FOREST ABOVEGROUND CARBON POOLS AND FLUXES USING MULTI-TEMPORAL LIDAR A report on field monitoring, remote sensing MMV, GIS integration, and modeling results for forestry field validation test to quantify aboveground tree biomass and carbon

    SciTech Connect

    Lee Spangler; Lee A. Vierling; Eva K. Stand; Andrew T. Hudak; Jan U.H. Eitel; Sebastian Martinuzzi

    2012-04-01

    Sound policy recommendations relating to the role of forest management in mitigating atmospheric carbon dioxide (CO{sub 2}) depend upon establishing accurate methodologies for quantifying forest carbon pools for large tracts of land that can be dynamically updated over time. Light Detection and Ranging (LiDAR) remote sensing is a promising technology for achieving accurate estimates of aboveground biomass and thereby carbon pools; however, not much is known about the accuracy of estimating biomass change and carbon flux from repeat LiDAR acquisitions containing different data sampling characteristics. In this study, discrete return airborne LiDAR data was collected in 2003 and 2009 across {approx}20,000 hectares (ha) of an actively managed, mixed conifer forest landscape in northern Idaho, USA. Forest inventory plots, established via a random stratified sampling design, were established and sampled in 2003 and 2009. The Random Forest machine learning algorithm was used to establish statistical relationships between inventory data and forest structural metrics derived from the LiDAR acquisitions. Aboveground biomass maps were created for the study area based on statistical relationships developed at the plot level. Over this 6-year period, we found that the mean increase in biomass due to forest growth across the non-harvested portions of the study area was 4.8 metric ton/hectare (Mg/ha). In these non-harvested areas, we found a significant difference in biomass increase among forest successional stages, with a higher biomass increase in mature and old forest compared to stand initiation and young forest. Approximately 20% of the landscape had been disturbed by harvest activities during the six-year time period, representing a biomass loss of >70 Mg/ha in these areas. During the study period, these harvest activities outweighed growth at the landscape scale, resulting in an overall loss in aboveground carbon at this site. The 30-fold increase in sampling density

  10. A Roof for the Lion's House

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Fans of the National Football League's Detroit Lions don't worry about gameday weather. Their magnificent new Pontiac Stadium has a domed, air-supported, fabric roof that admits light but protects the playing field and patrons from the elements. The 80,000-seat "Silverdome" is the world's largest fabric-covered structure-and aerospace technology played an important part in its construction. The key to economical construction of the Silverdome-and many other types of buildings-is a spinoff of fiber glass Beta yarn coated with Teflon TFE fluorocarbon resin. The big advance it offers is permanency. Fabric structures-tents, for example have been around since the earliest years of human civilization. But their coverings-hides, canvas and more recently plastics-were considered temporary; though tough, these fabrics were subject to weather deterioration. Teflon TFE-coated Beta Fiberglas is virtually impervious to the effects of weather and sunlight and it won't stretch, shrink, mildew or rot, thus has exceptional longevity; it is also very strong, lightweight, flame resistant and requires no periodic cleaning, because dirt will not stick to the surface of Teflon TFE. And to top all that, it costs only 30 to 40 percent as much as conventional roofing.

  11. Infiltration of a copper roof runoff through artificial barriers.

    PubMed

    Athanasiadis, K; Helmreich, B; Wilderer, P A

    2006-01-01

    On-site infiltration of a copper roof runoff may contribute to deterioration of the ground and ground water. To avoid such a negative effect the performance of two different technical systems, equipped with four different barrier materials, regarding copper elimination was examined in a field study. During the period March 2004 to January 2005, 16 rain events were examined. Copper concentrations between 200 and 11,000 microg/L in the roof runoff during a rain event were observed. The cover material of the roof and the drainage system were responsible for the high concentrations of copper in the roof runoff. It was evident that roof aspects facing towards the wind direction were receiving higher rainfall, thus were establishing higher copper runoff rates. The retention facilities have reached a performance of up to 97% regarding copper elimination.

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

    SciTech Connect

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

    1996-10-01

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

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

    SciTech Connect

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

    1996-12-31

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

  14. Radiant cooling by metal roofs in developing countries

    SciTech Connect

    Givoni, B.; Gulich, M.; Gomez, C.; Gomez, A.

    1996-10-01

    In many developing countries corrugated metal roofs are very common. During the nights the roof cools down rather quickly, acting in effect as an effective nocturnal radiator located directly above the living space. However, during the daytime hours the indoor climate in buildings with such roofs is often uncomfortably hot. Installing operable hinged interior insulating plates under the roof can reduce greatly the daytime heating without interfering too much with the cooling effect of such roofs during the nights. A model of this system (a test cell) was built and tested at UCLA. The paper describes the details of the model and its control mechanisms and provides information on the cooling performance of the system.

  15. Experimental analysis of green roof substrate detention characteristics.

    PubMed

    Yio, Marcus H N; Stovin, Virginia; Werdin, Jörg; Vesuviano, Gianni

    2013-01-01

    Green roofs may make an important contribution to urban stormwater management. Rainfall-runoff models are required to evaluate green roof responses to specific rainfall inputs. The roof's hydrological response is a function of its configuration, with the substrate - or growing media - providing both retention and detention of rainfall. The objective of the research described here is to quantify the detention effects due to green roof substrates, and to propose a suitable hydrological modelling approach. Laboratory results from experimental detention tests on green roof substrates are presented. It is shown that detention increases with substrate depth and as a result of increasing substrate organic content. Model structures based on reservoir routing are evaluated, and it is found that a one-parameter reservoir routing model coupled with a parameter that describes the delay to start of runoff best fits the observed data. Preliminary findings support the hypothesis that the reservoir routing parameter values can be defined from the substrate's physical characteristics.

  16. Effectiveness of Cool Roof Coatings with Ceramic Particles

    SciTech Connect

    Brehob, Ellen G; Desjarlais, Andre Omer; Atchley, Jerald Allen

    2011-01-01

    Liquid applied coatings promoted as cool roof coatings, including several with ceramic particles, were tested at Oak Ridge National Laboratory (ORNL), Oak Ridge, Tenn., for the purpose of quantifying their thermal performances. Solar reflectance measurements were made for new samples and aged samples using a portable reflectometer (ASTM C1549, Standard Test Method for Determination of Solar Reflectance Near Ambient Temperature Using a Portable Solar Reflectometer) and for new samples using the integrating spheres method (ASTM E903, Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres). Thermal emittance was measured for the new samples using a portable emissometer (ASTM C1371, Standard Test Method for Determination of Emittance of Materials Near Room 1 Proceedings of the 2011 International Roofing Symposium Temperature Using Portable Emissometers). Thermal conductivity of the coatings was measured using a FOX 304 heat flow meter (ASTM C518, Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus). The surface properties of the cool roof coatings had higher solar reflectance than the reference black and white material, but there were no significant differences among coatings with and without ceramics. The coatings were applied to EPDM (ethylene propylene diene monomer) membranes and installed on the Roof Thermal Research Apparatus (RTRA), an instrumented facility at ORNL for testing roofs. Roof temperatures and heat flux through the roof were obtained for a year of exposure in east Tennessee. The field tests showed significant reduction in cooling required compared with the black reference roof (~80 percent) and a modest reduction in cooling compared with the white reference roof (~33 percent). The coating material with the highest solar reflectivity (no ceramic particles) demonstrated the best overall thermal performance (combination of reducing the

  17. Mobilization and distribution of lead originating from roof dust and wet deposition in a roof runoff system.

    PubMed

    Yu, Jianghua; Yu, Haixia; Huang, Xiaogu

    2015-12-01

    In this research, the mobilization and distribution of lead originating in roof dust and wet deposition were investigated within a roof dust-rooftop-runoff system. The results indicated that lead from roof dust and wet deposition showed different transport dynamics in runoff system and that this process was significantly influenced by the rainfall intensity. Lead present in the roof dust could be easily washed off into the runoff, and nearly 60 % of the total lead content was present in particulate form. Most of the lead from the roof dust was transported during the late period of rainfall; however, the lead concentration was higher for several minutes at the rainfall beginning. Even though some of the lead from wet deposition, simulated with a standard isotope substance, was adsorbed onto adhered roof dust and/or retained on rooftop in runoff system, most of it (50-82 %) remained as dissolved lead in the runoff for rainfall events of varying intensity. Regarding the distribution of lead in the runoff system, the results indicated that it could be carried in the runoff in dissolved and particulate form, be adsorbed to adhered roof dust, or remain on the rooftop because of adsorption to the roof material. Lead from the different sources showed different distribution patterns that were also related to the rainfall intensity. Higher rainfall intensity resulted in a higher proportion of lead in the runoff and a lower proportion of lead remaining on the rooftop.

  18. Methods for estimating aboveground biomass and its components for Douglas-fir and lodgepole pine trees

    Treesearch

    K.P. Poudel; H. Temesgen

    2016-01-01

    Estimating aboveground biomass and its components requires sound statistical formulation and evaluation. Using data collected from 55 destructively sampled trees in different parts of Oregon, we evaluated the performance of three groups of methods to estimate total aboveground biomass and (or) its components based on the bias and root mean squared error (RMSE) that...

  19. Wind, rain and bacteria: The effect of weather on the microbial composition of roof-harvested rainwater.

    PubMed

    Evans, C A; Coombes, P J; Dunstan, R H

    2006-01-01

    The microbiological and chemical quality of tank-stored rainwater is impacted directly by roof catchment and subsequent run-off contamination, via direct depositions by birds and small mammals, decay of accumulated organic debris, and atmospheric deposition of airborne micro-organisms and chemical pollutants. Previous literature reports on roof water quality have given little consideration to the relative significance of airborne micro-organisms. This study involved analyses of direct roof run-off at an urban housing development in Newcastle, on the east coast of Australia. A total of 77 samples were collected during 11 separate rainfall events, and microbial counts and mean concentrations of several ionic contaminants were matched to climatic data corresponding to each of the monitored events. Conditions both antecedent to, and those prevailing during each event, were examined to investigate the influence of certain meteorological parameters on the bacterial composition of the roof water and indirectly assess the relative contribution of airborne micro-organisms to the total bacterial load. Results indicated that airborne micro-organisms represented a significant contribution to the bacterial load of roof water at this site, and that the overall contaminant load was influenced by wind velocities, while the profile (composition) of the load varied with wind direction. The implications of these findings to the issues of tank water quality and health risk analysis, appropriate usage and system design are discussed.

  20. Drought-avoiding plants with low water use can achieve high rainfall retention without jeopardising survival on green roofs.

    PubMed

    Szota, Christopher; Farrell, Claire; Williams, Nicholas S G; Arndt, Stefan K; Fletcher, Tim D

    2017-12-15

    Green roofs are increasingly being used among the suite of tools designed to reduce the volume of surface water runoff generated by cities. Plants provide the primary mechanism for restoring the rainfall retention capacity of green roofs, but selecting plants with high water use is likely to increase drought stress. Using empirically-derived plant physiological parameters, we used a water balance model to assess the trade-off between rainfall retention and plant drought stress under a 30-year climate scenario. We compared high and low water users with either drought avoidance or drought tolerance strategies. Green roofs with low water-using, drought-avoiding species achieved high rainfall retention (66-81%) without experiencing significant drought stress. Roofs planted with other strategies showed high retention (72-90%), but they also experienced >50days of drought stress per year. However, not all species with the same strategy behaved similarly, therefore selecting plants based on water use and drought strategy alone does not guarantee survival in shallow substrates where drought stress can develop quickly. Despite this, it is more likely that green roofs will achieve high rainfall retention with minimal supplementary irrigation if planted with low water users with drought avoidance strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Testing cathodic protection systems on aboveground storage tanks

    SciTech Connect

    Garrity, K.C.

    1995-12-31

    The evaluation of cathodic protection systems on aboveground storage tanks presents a unique challenge. Paramount with selection of system type is the method of verification that corrosion control has indeed been achieved. Past experience indicates that standard monitoring procedures intended to determine satisfaction of the industry recognized criteria may not be adequate in analyzing the degree of protection being afforded a storage tank resting on the ground. The standard method of determining the effectiveness of cathodic protection on any structure is the structure-to-electrolyte potential measurement. These measurements are performed utilizing a high impedance voltmeter and a stable, reproducible reference electrode contacting the electrolyte. The paper describes several case histories to illustrate methods.

  2. Stormwater quality from extensive green roofs in a subtropical region

    NASA Astrophysics Data System (ADS)

    Onis Pessoa, Jonas; Allasia, Daniel; Tassi, Rutineia; Vaz Viega, Juliana; Fensterseifer, Paula

    2016-04-01

    Green roofs have increasingly become an integral part of urban environments, mainly due to their aesthetic benefits, thermal comfort and efficiency in controlling excess runoff. However, the effects of this emerging technology in the qualitative characteristics of rainwater is still poorly understood. In this study was evaluated the effect of two different extensive green roofs (EGRs) and a traditional roof built with corrugated fiber cement sheets (control roof) in the quality of rainwater, in a subtropical climate area in the city of Santa Maria, in southern Brazil. The principal variant between the two EGRs were the type of plant species, time since construction, soil depth and the substrate characteristics. During the monitoring period of the experiment, between the months of April and December of 2015 fourteen rainfall events were selected for qualitative analysis of water from the three roofs and directly from rainfall. It was analyzed physical (turbidity, apparent color, true color, electrical conductivity, total solids, dissolved solids, suspended solids and temperature), chemical (pH, phosphate, total nitrogen, nitrate, nitrite, chloride, sulfate, BOD, iron and total hardness), heavy metals (copper, zinc, lead and chromium) and microbiological parameters (total coliforms and E. coli). It was also characterized the substrates used in both extensive green roofs. The results showed that the quality of the water drained from EGR s was directly influenced by their substrates (in turn containing significant levels of nutrients, organic matter and some metals). The passage of rainwater through green roofs and control roof resulted in the elevation of pH, allowing the conversion of the slightly acidic rainfall into basic water. Similarly, on both types of roofs occurred an increase of the values of most of the physical, chemical and microbiological parameters compared to rainwater. This same trend was observed for heavy metals, although with a much smaller degree

  3. Evaluating lidar point densities for effective estimation of aboveground biomass

    USGS Publications Warehouse

    Wu, Zhuoting; Dye, Dennis G.; Stoker, Jason M.; Vogel, John M.; Velasco, Miguel G.; Middleton, Barry R.

    2016-01-01

    The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) was recently established to provide airborne lidar data coverage on a national scale. As part of a broader research effort of the USGS to develop an effective remote sensing-based methodology for the creation of an operational biomass Essential Climate Variable (Biomass ECV) data product, we evaluated the performance of airborne lidar data at various pulse densities against Landsat 8 satellite imagery in estimating above ground biomass for forests and woodlands in a study area in east-central Arizona, U.S. High point density airborne lidar data, were randomly sampled to produce five lidar datasets with reduced densities ranging from 0.5 to 8 point(s)/m2, corresponding to the point density range of 3DEP to provide national lidar coverage over time. Lidar-derived aboveground biomass estimate errors showed an overall decreasing trend as lidar point density increased from 0.5 to 8 points/m2. Landsat 8-based aboveground biomass estimates produced errors larger than the lowest lidar point density of 0.5 point/m2, and therefore Landsat 8 observations alone were ineffective relative to airborne lidar for generating a Biomass ECV product, at least for the forest and woodland vegetation types of the Southwestern U.S. While a national Biomass ECV product with optimal accuracy could potentially be achieved with 3DEP data at 8 points/m2, our results indicate that even lower density lidar data could be sufficient to provide a national Biomass ECV product with accuracies significantly higher than that from Landsat observations alone.

  4. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2005-04-15

    In this quarter, the field, theoretical and programming works have been performed toward achieving the research goals set in the proposal. The main accomplishments in this quarter included: (1) one more field test has been conducted in an underground coal mine, (2) optimization studies of the control parameters have been conducted, (3) the relationship among feed pressure, penetration rate and rotation rate seems to be a good indicator for estimating rock strength when both penetration rate and rotation rate are controlled or kept constant, (4) the empirical equations for eliminating the machine effect on drilling parameters were developed and verified, and (5) a real time roof geology mapping system for roof bolters in limestone mine, including a special version of the geology mapping program and hardware, performs very well in underground production condition.

  5. EVALUATION OF ROOF BOLTING REQUIREMENTS BASED ON IN-MINE ROOF BOLTER DRILLING

    SciTech Connect

    Syd S. Peng

    2001-04-15

    In this quarter, the research effort is to develop the drill control unit (DCU) that acquire, store drilling parameters and control the drilling operation. The relevant publications have been reviewed and the methodology developed by previous researchers has been evaluated using the collected data in our laboratory and field tests conducted prior to the start of this project. Numerical modeling for exploring roof bolting mechanism has been started.

  6. The Advancement of Cool Roof Standards in China from 2010 to 2015

    SciTech Connect

    Ge, Jing; Levinson, Ronnen M.

    2016-11-01

    Since the initiation of the U.S.-China Clean Energy Research Center-Building Energy Efficiency (CERC-BEE) cool roof research collaboration between the Lawrence Berkeley National Laboratory Heat Island Group and Chinese institutions in 2010, new cool surface credits (insulation trade- offs) have been adopted in Chinese building energy efficiency standards, industry standards, and green building standards. JGJ 75-2012: Design Standard for Energy Efficiency of Residential Buildings in Hot Summer and Warm Winter Zone became the first national level standard to provide cool surface credits. GB/T 50378-2014: Assessment Standard for Green Building is the first national level green building standard that offers points for heat island mitigation. JGJ/T 359-2015: Technical Specification for Application of Architectural Reflective Thermal Insulation Coating is the first industry standard that offers cool coating credits for both public and residential buildings in all hot-summer climates (Hot Summer/Cold Winter, Hot Summer/Warm Winter). As of December 2015, eight provinces or municipalities in hot-summer regions have credited cool surfaces credits in their residential and/or public building design standards; five other provinces or municipalities in hot-summer regions recommend, but do not credit, the use of cool surfaces in their building design standards. Cool surfaces could be further advanced in China by including cool roof credits for residential and public building energy efficiency standards in all hot-summer regions; developing a standardized process for natural exposure and aged-property rating of cool roofing products; and adapting the U.S.-developed laboratory aging process for roofing materials to replicate solar reflectance changes induced by natural exposure in China.

  7. Quality of roof-harvested rainwater--comparison of different roofing materials.

    PubMed

    Lee, Ju Young; Bak, Gippeum; Han, Mooyoung

    2012-03-01

    The objective of the study reported in this paper was to assess the quality of harvested rainwater on the basis of the roofing materials used and the presence of lichens/mosses on the roofing surface. Four pilot structures with different roofing materials (i.e., wooden shingle tiles, concrete tiles, clay tiles [Gi-Wa] and galvanized steel) were installed in a field. The galvanized steel was found to be the most suitable for rainwater harvesting applications, with their resulting physical and chemical water quality parameters meeting the Korean guidelines for drinking water quality (e.g., pH (5.8-8.5), TSS <500 mg/L, NO(3)(-) < 10 mg/L, SO(4)(2-) < 200 mg/L, Al < 0.2 mg/L, Cu < 1 mg/L, Fe < 0.3 mg/L, Pb < 0.05 mg/L, Zn < 1 mg/L, and E. coli (No detection)). In the galvanized steel case, the relatively high water quality was probably due to ultraviolet light and the high temperature effectively disinfecting the harvested rainwater. It was also found that the presence of lichens and mosses may adversely affect the physical, chemical and microbiological quality of rainwater. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Flexible shaft and roof drilling system

    SciTech Connect

    Blanz, J.H.

    1981-09-22

    A system for drilling holes in the roof of a mine has a flexible shaft with a pair of oppositely wound, coaxial flat bands. One of the flat bands defines an inner spring that is wound right handed into a helical configuration, adjacent convolutions being in nesting relationship to one another. The other flat band defines an outer spring that is wound left handed into a helical configuration about the inner band, adjacent convolutions being nesting relationship with one another. A transition member that is configured to hold a rock bit is mounted to one end of the flexible shaft. When torque and thrust are applied to the flexible shaft by a driver, the inner spring expands outwardly and the outer spring contracts inwardly to form a relatively rigid shaft.

  9. Flexible shaft and roof drilling system

    DOEpatents

    Blanz, John H.

    1981-01-01

    A system for drilling holes in the roof of a mine has a flexible shaft with a pair of oppositely wound, coaxial flat bands. One of the flat bands defines an inner spring that is wound right handed into a helical configuration, adjacent convolutions being in nesting relationship to one another. The other flat band defines an outer spring that is wound left handed into a helical configuration about the inner band, adjacent convolutions being nesting relationship with one another. A transition member that is configured to hold a rock bit is mounted to one end of the flexible shaft. When torque and thrust are applied to the flexible shaft by a driver, the inner spring expands outwardly and the outer spring contracts inwardly to form a relatively rigid shaft.

  10. Adventures on the roof of the world

    USGS Publications Warehouse

    Leslie, David M.

    2013-01-01

    To conduct field biology requires tenacity, grit, and flexibility; to endeavor to achieve conservation success requires patience, persistence, and passion. The essence of field biology and the hope for conservation success are both reflected admirably in George B. Schaller's most recent book, Tibet Wild: A Naturalist's Journeys on the Roof of the World. I can think of no living biologist who embodies these characteristics more than Schaller does. Nearly 80 years old, he still regularly treks in faraway lands, observing and recording the natural history of species that the vast majority of us will never see in the wild. Schaller is a vanguard, and Tibet Wild, like his other books, is a sentinel of urgent conservation need.

  11. Air-quality implications of widespread adoption of cool roofs on ozone and particulate matter in southern California

    NASA Astrophysics Data System (ADS)

    Epstein, Scott A.; Lee, Sang-Mi; Katzenstein, Aaron S.; Carreras-Sospedra, Marc; Zhang, Xinqiu; Farina, Salvatore C.; Vahmani, Pouya; Fine, Philip M.; Ban-Weiss, George

    2017-08-01

    The installation of roofing materials with increased solar reflectance (i.e., “cool roofs”) can mitigate the urban heat island effect and reduce energy use. In addition, meteorological changes, along with the possibility of enhanced UV reflection from these surfaces, can have complex impacts on ozone and PM2.5 concentrations. We aim to evaluate the air-quality impacts of widespread cool-roof installations prescribed by California’s Title 24 building energy efficiency standards within the heavily populated and polluted South Coast Air Basin (SoCAB). Development of a comprehensive rooftop area database and evaluation of spectral reflectance measurements of roofing materials allows us to project potential future changes in solar and UV reflectance for simulations using the Weather Research Forecast and Community Multiscale Air Quality (CMAQ) models. 2012 meteorological simulations indicate a decrease in daily maximum temperatures, daily maximum boundary layer heights, and ventilation coefficients throughout the SoCAB upon widespread installation of cool roofs. CMAQ simulations show significant increases in PM2.5 concentrations and policy-relevant design values. Changes in 8-h ozone concentrations depend on the potential change in UV reflectance, ranging from a decrease in population-weighted concentrations when UV reflectance remains unchanged to an increase when changes in UV reflectance are at an upper bound. However, 8-h policy-relevant ozone design values increase in all cases. Although the other benefits of cool roofs could outweigh small air-quality penalties, UV reflectance standards for cool roofing materials could mitigate these negative consequences. Results of this study motivate the careful consideration of future rooftop and pavement solar reflectance modification policies.

  12. Comparison of software models for energy savings from cool roofs

    DOE PAGES

    New, Joshua; Miller, William A.; Huang, Yu; ...

    2015-06-07

    For this study, a web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. RSC simulates multiple roof and attic technologies for side-by-side comparison including reflective roofs, different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. Annual simulations of hour-by-hour, whole-building performance are used to provide estimated annual energy and cost savings from reduced HVAC use. While RSC reported similar cooling savingsmore » to other simulation engines, heating penalty varied significantly. RSC results show reduced cool roofing cost-effectiveness, thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC's projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus. Also included are comparisons to previous simulation-based studies, analysis of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model. Finally, radiant heat transfer and duct interaction not previously modeled is considered a major contributor to heating penalties.« less

  13. Roof Moisture Surveys: Current State Of The Technology

    NASA Astrophysics Data System (ADS)

    Tobiasson, Wayne

    1983-03-01

    Moisture is the big enemy of compact roofing systems. Non-destructive nuclear, capacitance and infrared methods can all find wet insulation in such roofs but a few core samples are needed for verification. Nuclear and capacitance surveys generate quantitative results at grid points but examine only a small portion of the roof. Quantitative results are not usually provided by infrared scanners but they can rapidly examine every square inch of the roof. Being able to find wet areas when they are small is an important advantage. Prices vary with the scope of the investigation. For a particular scope, the three techniques are often cost-competitive. The limitations of each technique are related to the people involved as well as the equipment. When the right people are involved, non-destructive surveys are a very effective method for improving the long-term performance and reducing the life-cycle costs of roofing systems. Plans for the maintenance, repair or replacement of a roof should include a roof moisture survey.

  14. Comparison of software models for energy savings from cool roofs

    SciTech Connect

    New, Joshua; Miller, William A.; Huang, Yu; Levinson, Ronnen

    2015-06-07

    For this study, a web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. RSC simulates multiple roof and attic technologies for side-by-side comparison including reflective roofs, different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. Annual simulations of hour-by-hour, whole-building performance are used to provide estimated annual energy and cost savings from reduced HVAC use. While RSC reported similar cooling savings to other simulation engines, heating penalty varied significantly. RSC results show reduced cool roofing cost-effectiveness, thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC's projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus. Also included are comparisons to previous simulation-based studies, analysis of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model. Finally, radiant heat transfer and duct interaction not previously modeled is considered a major contributor to heating penalties.

  15. Fatal falls from roofs among U.S. construction workers.

    PubMed

    Dong, Xiuwen Sue; Choi, Sang D; Borchardt, James G; Wang, Xuanwen; Largay, Julie A

    2013-02-01

    This study examined trends and patterns of fatal falls from roofs in the U.S. construction industry over an 18-year period (1992-2009), with detailed analysis for 2003-2009. Two large national datasets were analyzed: the U.S. Bureau of Labor Statistics' Census of Fatal Occupational Injuries and the Current Population Survey. Roof fatalities accounted for one-third of fatal falls in construction in 1992-2009. A disproportionately high percentage (67%) of deaths from roof falls occurred in small construction establishments (1-10 employees). Roofers, ironworkers, workers employed with roofing contractors, or working at residential construction sites, had a higher risk of roof fatalities. A higher rate of roof fatalities was also found among younger (<20years) and older (>44years) workers, Hispanics, and immigrant workers. Roof fatalities corresponded with economic cycles and differed among construction subgroups and worksites. Prevention strategies should target high-risk worker groups and small establishments. Copyright © 2012 National Safety Council and Elsevier Ltd. All rights reserved.

  16. Comparative life cycle assessment of standard and green roofs.

    PubMed

    Saiz, Susana; Kennedy, Christopher; Bass, Brad; Pressnail, Kim

    2006-07-01

    Life cycle assessment (LCA) is used to evaluate the benefits, primarily from reduced energy consumption, resulting from the addition of a green roof to an eight story residential building in Madrid. Building energy use is simulated and a bottom-up LCA is conducted assuming a 50 year building life. The key property of a green roof is its low solar absorptance, which causes lower surface temperature, thereby reducing the heat flux through the roof. Savings in annual energy use are just over 1%, but summer cooling load is reduced by over 6% and reductions in peak hour cooling load in the upper floors reach 25%. By replacing the common flat roof with a green roof, environmental impacts are reduced by between 1.0 and 5.3%. Similar reductions might be achieved by using a white roof with additional insulation for winter, but more substantial reductions are achieved if common use of green roofs leads to reductions in the urban heat island.

  17. A field study to evaluate runoff quality from green roofs.

    PubMed

    Vijayaraghavan, K; Joshi, U M; Balasubramanian, R

    2012-03-15

    Green (vegetated) roofs are emerging as practical strategies to improve the environmental quality of cities. However, the impact of green roofs on the storm water quality remains a topic of concern to city planners and environmental policy makers. This study investigated whether green roofs act as a source or a sink of various metals (Na, K, Ca, Mg, Al, Fe, Cu, Cd, Pb, Zn, Mn, Cr, Ni, Li and Co), inorganic anions (NO3-, NO2-, PO4(3-), SO4(2-), Cl-, F- and Br-) and cation (NH4+). A series of green roof assemblies were constructed. Four different real rain events and several artificial rain events were considered for the study. Results showed that concentrations of most of the chemical components in runoff were highest during the beginning of rain events and subsided in the subsequent rain events. Some of the important components present in the runoff include Na, K, Ca, Mg, Li, Fe, Al, Cu, NO3-, PO4(3-) and SO4(2-). However, the concentration of these chemical components in the roof runoff strongly depends on the nature of substrates used in the green roof and the volume of rain. Based on the USEPA standards for freshwater quality, we conclude that the green roof used in this study is reasonably effective except that the runoff contains significant amounts of NO3- and PO4(3-). Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Rainwater runoff retention on an aged intensive green roof.

    PubMed

    Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

    2013-09-01

    Urban areas are characterised by large proportions of impervious surfaces which increases rainwater runoff and the potential for surface water flooding. Increased precipitation is predicted under current climate change projections, which will put further pressure on urban populations and infrastructure. Roof greening can be used within flood mitigation schemes to restore the urban hydrological balance of cities. Intensive green roofs, with their deeper substrates and higher plant biomass, are able to retain greater quantities of runoff, and there is a need for more studies on this less common type of green roof which also investigate the effect of factors such as age and vegetation composition. Runoff quantities from an aged intensive green roof in Manchester, UK, were analysed for 69 rainfall events, and compared to those on an adjacent paved roof. Average retention was 65.7% on the green roof and 33.6% on the bare roof. A comprehensive soil classification revealed the substrate, a mineral soil, to be in good general condition and also high in organic matter content which can increase the water holding capacity of soils. Large variation in the retention data made the use of predictive regression models unfeasible. This variation arose from complex interactions between Antecedant Dry Weather Period (ADWP), season, monthly weather trends, and rainfall duration, quantity and peak intensity. However, significantly lower retention was seen for high rainfall events, and in autumn, which had above average rainfall. The study period only covers one unusually wet year, so a longer study may uncover relationships to factors which can be applied to intensive roofs elsewhere. Annual rainfall retention for Manchester city centre could be increased by 2.3% by a 10% increase in intensive green roof construction. The results of this study will be of particular interest to practitioners implementing greenspace adaptation in temperate and cool maritime climates. Copyright © 2013

  19. An environmental cost-benefit analysis of alternative green roofing strategies

    NASA Astrophysics Data System (ADS)

    Richardson, M.; William, R. K.; Goodwell, A. E.; Le, P. V.; Kumar, P.; Stillwell, A. S.

    2016-12-01

    Green roofs and cool roofs are alternative roofing strategies that mitigate urban heat island effects and improve building energy performance. Green roofs consist of soil and vegetation layers that provide runoff reduction, thermal insulation, and potential natural habitat, but can require regular maintenance. Cool roofs involve a reflective layer that reflects more sunlight than traditional roofing materials, but require additional insulation during winter months. This study evaluates several roofing strategies in terms of energy performance, urban heat island mitigation, water consumption, and economic cost. We use MLCan, a multi-layer canopy model, to simulate irrigated and non-irrigated green roof cases with shallow and deep soil depths during the spring and early summer of 2012, a drought period in central Illinois. Due to the dry conditions studied, periodic irrigation is implemented in the model to evaluate its effect on evapotranspiration. We simulate traditional and cool roof scenarios by altering surface albedo and omitting vegetation and soil layers. We find that both green roofs and cool roofs significantly reduce surface temperature compared to the traditional roof simulation. Cool roof temperatures always remain below air temperature and, similar to traditional roofs, require low maintenance. Green roofs remain close to air temperature and also provide thermal insulation, runoff reduction, and carbon uptake, but might require irrigation during dry periods. Due to the longer lifetime of a green roof compared to cool and traditional roofs, we find that green roofs realize the highest long term cost savings under simulated conditions. However, using longer-life traditional roof materials (which have a higher upfront cost) can help decrease this price differential, making cool roofs the most affordable option due to the higher maintenance costs associated with green roofs

  20. Sequential effects of root and foliar herbivory on aboveground and belowground induced plant defense responses and insect performance.

    PubMed

    Wang, Minggang; Biere, Arjen; Van der Putten, Wim H; Bezemer, T Martijn

    2014-05-01

    Plants are often simultaneously or sequentially attacked by multiple herbivores and changes in host plants induced by one herbivore can influence the performance of other herbivores. We examined how sequential feeding on the plant Plantago lanceolata by the aboveground herbivore Spodoptera exigua and the belowground herbivore Agriotes lineatus influences plant defense and the performance of both insects. Belowground herbivory caused a reduction in the food consumption by the aboveground herbivore independent of whether it was initiated before, at the same time, or after that of the aboveground herbivore. By contrast, aboveground herbivory did not significantly affect belowground herbivore performance, but significantly reduced the performance of later arriving aboveground conspecifics. Interestingly, belowground herbivores negated negative effects of aboveground herbivores on consumption efficiency of their later arriving conspecifics, but only if the belowground herbivores were introduced simultaneously with the early arriving aboveground herbivores. Aboveground-belowground interactions could only partly be explained by induced changes in an important class of defense compounds, iridoid glycosides (IGs). Belowground herbivory caused a reduction in IGs in roots without affecting shoot levels, while aboveground herbivory increased IG levels in roots in the short term (4 days) but only in the shoots in the longer term (17 days). We conclude that the sequence of aboveground and belowground herbivory is important in interactions between aboveground and belowground herbivores and that knowledge on the timing of exposure is essential to predict outcomes of aboveground-belowground interactions.