Digging the New York City Skyline: soil fungal communities in green roofs and city parks.

PubMed

McGuire, Krista L; Payne, Sara G; Palmer, Matthew I; Gillikin, Caitlyn M; Keefe, Dominique; Kim, Su Jin; Gedallovich, Seren M; Discenza, Julia; Rangamannar, Ramya; Koshner, Jennifer A; Massmann, Audrey L; Orazi, Giulia; Essene, Adam; Leff, Jonathan W; Fierer, Noah

2013-01-01

In urban environments, green roofs provide a number of benefits, including decreased urban heat island effects and reduced energy costs for buildings. However, little research has been done on the non-plant biota associated with green roofs, which likely affect their functionality. For the current study, we evaluated whether or not green roofs planted with two native plant communities in New York City functioned as habitats for soil fungal communities, and compared fungal communities in green roof growing media to soil microbial composition in five city parks, including Central Park and the High Line. Ten replicate roofs were sampled one year after planting; three of these roofs were more intensively sampled and compared to nearby city parks. Using Illumina sequencing of the fungal ITS region we found that green roofs supported a diverse fungal community, with numerous taxa belonging to fungal groups capable of surviving in disturbed and polluted habitats. Across roofs, there was significant biogeographical clustering of fungal communities, indicating that community assembly of roof microbes across the greater New York City area is locally variable. Green roof fungal communities were compositionally distinct from city parks and only 54% of the green roof taxa were also found in the park soils. Phospholipid fatty acid analysis revealed that park soils had greater microbial biomass and higher bacterial to fungal ratios than green roof substrates. City park soils were also more enriched with heavy metals, had lower pH, and lower quantities of total bases (Ca, K, and Mg) compared to green roof substrates. While fungal communities were compositionally distinct across green roofs, they did not differentiate by plant community. Together, these results suggest that fungi living in the growing medium of green roofs may be an underestimated component of these biotic systems functioning to support some of the valued ecological services of green roofs.

A Model of Equilibrium Conditions of Roof Rock Mass Giving Consideration to the Yielding Capacity of Powered Supports

NASA Astrophysics Data System (ADS)

Jaszczuk, Marek; Pawlikowski, Arkadiusz

2017-12-01

The work presents the model of interactions between the powered roof support units and the rock mass, while giving consideration to the yielding capacity of the supports - a value used for the analysis of equilibrium conditions of roof rock mass strata in geological and mining conditions of a given longwall. In the model, the roof rock mass is kept in equilibrium by: support units, the seam, goafs, and caving rocks (Fig. 1). In the assumed model of external load on the powered roof support units it is a new development - in relation to the model applied in selection of supports based on the allowable deflection of roof theory - that the load bearing capacity is dependent on the increment of the inclination of the roof rock mass and on the properties of the working medium, while giving consideration to the air pockets in the hydraulic systems, the load of the caving rocks on the caving shield, introducing the RA support value of the roof rock mass by the coal seam as a closed-form expression and while giving consideration to the additional support provided by the rocks of the goaf as a horizontal component R01H of the goaf reaction. To determine the roof maintenance conditions it is necessary to know the characteristics linking the yielding capacity of the support units with the heading convergence, which may be measured as the inclination angle of the roof rock mass. In worldwide mining, Ground Reaction Curves are used, which allow to determine the required yielding capacity of support units based on the relation between the load exerted on the unit and the convergence of the heading ensuring the equilibrium of the roof rock mass. (Figs. 4 and 8). The equilibrium of the roof rock mass in given conditions is determined at the displacement of the rock mass by the α angle, which impacts the following values: yielding capacity of units FN, vertical component of goaf reaction R01V and the horizontal component of goaf reaction R01H. In the model of load on the support units giving consideration to the load of the caving shield, a model of support unit was used that allows for unequivocal determination of the yielding capacity of the support with consideration given to the height of the unit in use and the change in the inclination of the canopy resulting from the displacement of the roof of the longwall. The yielding capacity of the support unit and its point of application on the canopy was determined using the method of units which allows for the internal forces to be manifested. The weight of the rock mass depends on the geological and mining conditions, for which the shape and dimensions of the rock mass affecting the support unit are determined. The resultant force of the pressure of gob on the gob shield was calculated by assuming that the load may be understood as a pressure of ground on a wall. This required the specification of the volume of the fallen rocks that affect the unit of powered roof supports (Fig. 2). To determine the support of the roof rock mass by the coal seam, experience of the Australian mining industry was used. Experiments regarding the strength properties of coal have exhibited that vertical deformation, at which the highest seam reaction occurs while supporting the roof rock mass, amounts to 0.5% of the longwall's height. The measure of the width of the contact area between the rock mass and the seam is the width of the additional uncovering of the face roof due to spalling of seam topcorners da (Fig. 2). With the above parameters and the value of the modulus of elasticity of coal in mind, the value of the seam's reaction may be estimated using the dependence (2). The vertical component of the goafs' reaction may be determined based on the strength characteristics of the fallen roof, the contact area of the rock mass with the fallen roof and the mean strain of the fallen roof at the area of contact. In the work by Pawlikowski (2014), a research procedure was proposed which encompasses model tests and exploitation tests of the loads exerted on the support units, aimed at the determination of the vertical component of the goaf reaction (Fig. 5). Based on duty cycles of powered roof support units, a mean value of the indicator of contact stiffness between the roof rock mass and the rocks constituting the caving is determined, assuming the linear dependence between the horizontal reaction and the heading convergence. The parameter allows for the determination of the horizontal component of the goafs' reaction in the external loading model of support units and allows for the determination of the required yielding capacity of supports, required to ensure the equilibrium of the roof rock mass. The experimentally verified model of the external loading of the units was used to conduct simulations of interactions between the KOPEX-095/17-POz support unit and the rock mass in a face characterized by the height of 1.6 m. Based on the data obtained in experiment, the variability of the yielding capacity of the support units was analyzed. A yielding capacity inclination angle of the units was determined for the registered curves (Figs. 6 and 7). At the same time, the presentation of the lines corresponding to the required yielding capacity of units and characterizing the deformability of the support units, allows for the prediction of the yielding capacity of the powered supports and the convergence of the heading in the conditions of a given face (Fig. 9).

Advanced Energy Efficient Roof System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jane Davidson

2008-09-30

Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implementmore » more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic. The 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 the study. The market potential is enhanced through construction activity levels in target markets. Southern markets, from Florida to Texas account for 50 percent of the total new construction angled-roof volume. California contributes an additional 13 percent share of market volume. These states account for 28 to 30 million squares (2.8 to 3 billion square feet) of new construction angled roof opportunity. The major risk to implementation is the uncertainty of incorporating new design and construction elements into the construction process. By coordinating efforts to enhance the drivers for adoption and minimize the barriers, the panelized roof system stands to capitalize on a growing market demand for energy efficient building alternatives and create a compelling case for market adoption.« less

Full pillar extraction at the Kathleen Mine with mobile roof supports

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grimm, E.S.

1994-12-31

The Voest Alpine Breaker Line Supports (ABLS) resemble self-propelled longwall shields. Each individual unit consists of four hydraulic legs extending from the base of the unit, pressing a solid flat canopy against the mine roof. Each support unit is capable of exerting 606 tons of force against the roof. A chain curtain on the sides and rear protects the interior of the support from falling rock. The internal scissoring lemniscate design allows for parallel movement of the canopy as it is raised or lowered. Each ABLS has 750 feet of 4 AWG trailing cable to supply 480 volts AC tomore » a permissible controller and a 40 hp explosion-proof electrical motor. The hydraulic pump and reservoir are self-contained and protected with an automatic fire suppression system.« less

Roof instability characteristics and pre-grouting of the roof caving zone in residual coal mining

NASA Astrophysics Data System (ADS)

Zhao, Tong; Liu, Changyou

2017-12-01

Abandoned roadways and roof caving zones are commonly found in residual coal, and can destroy the integrity of the coal seam and roof. Resulting from mining-induced stress, continuous collapse and fracture instability in roof caving zones (RCZs) jeopardize the safety and efficiency of residual coal mining. Based on the engineering geology conditions of remining face 3101 in Shenghua Mine, the roof fracture and instability features of the RCZ were analyzed through physical simulation, theoretical analysis, and field measurements. In this case, influenced by the RCZ, the main roof across the RCZ fractured and rotated towards the goaf, greatly increasing the working resistance, and crushing the supports. The sudden instability of the coal pillars weakened its support of the main roof, thus resulting in long-key blocks across the RCZ and hinged roof structures, which significantly decreased the stability of the underlying immediate roof. This study establishes a mechanical model for the interactions between the surrounding rock and the supports in the RCZ, determines the reasonable working resistance, and examines the use of pre-grouting solidification restoration technology (PSRT) to solidify the RCZ and reinforce the coal pillars—thus increasing their bearing capacity. Field measurements revealed no roof flaking, inhomogeneous loading or support crushing, indicating that the PSRT effectively controlled the surrounding rock of the RCZ.

Thin soil layer of green roof systems studied by X-Ray CT

NASA Astrophysics Data System (ADS)

Šácha, Jan; Jelínková, Vladimíra; Dohnal, Michal

2016-04-01

The popular non-invasive visualization technique of X-ray computed tomography (CT) has been used for 3D examination of thin soil layer of vegetated roof systems. The two categories of anthropogenic soils, usually used for green roof systems, were scanned during the first months after green roof system construction. First was represented by stripped topsoil with admixed crushed bricks and was well graded in terms of particle size distribution. The other category represented a commercial lightweight technogenic substrate. The undisturbed soil samples of total volume of 62.8 ccm were studied be means of X-ray Computed Tomography using X-ray Inspection System GE Phoenix Nanomex 180T with resulting spatial resolution about 57 μm in all directions. For both soil categories visible macroporosity, connectivity (described by the Euler characteristic), dimensionless connectivity and critical cross section of pore network were determined. Moreover, the temporal structural changes of studied soils were discussed together with heat and water regime of the green roof system. The analysis of CT images of anthropogenic soils was problematic due to the different X-ray attenuation of individual constituents. The correct determination of the threshold image intensity differentiating the soil constituents from the air phase had substantial importance for soil pore network analyses. However, X-ray CT derived macroporosity profiles reveal significant temporal changes notably in the soil comprised the stripped topsoil with admixed crushed bricks. The results implies that the technogenic substrate is structurally more stable over time compared to the stripped topsoil. 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.

77 FR 812 - Petitions for Modification of Application of Existing Mandatory Safety Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-06

... (Permissible electric face equipment; maintenance). Modification Request: The petitioner requests a... its shuttle cars, roof bolters, and mobile roof supports at the Campbells Creek No. 7 Mine and Blue...-volt shuttle cars, 480-volt roof bolters, and 480-volt mobile roof supports will not exceed 900 feet...

A case study of multi-seam coal mine entry stability analysis with strength reduction method

PubMed Central

Tulu, Ihsan Berk; Esterhuizen, Gabriel S; Klemetti, Ted; Murphy, Michael M.; Sumner, James; Sloan, Michael

2017-01-01

In this paper, the advantage of using numerical models with the strength reduction method (SRM) to evaluate entry stability in complex multiple-seam conditions is demonstrated. A coal mine under variable topography from the Central Appalachian region is used as a case study. At this mine, unexpected roof conditions were encountered during development below previously mined panels. Stress mapping and observation of ground conditions were used to quantify the success of entry support systems in three room-and-pillar panels. Numerical model analyses were initially conducted to estimate the stresses induced by the multiple-seam mining at the locations of the affected entries. The SRM was used to quantify the stability factor of the supported roof of the entries at selected locations. The SRM-calculated stability factors were compared with observations made during the site visits, and the results demonstrate that the SRM adequately identifies the unexpected roof conditions in this complex case. It is concluded that the SRM can be used to effectively evaluate the likely success of roof supports and the stability condition of entries in coal mines. PMID:28239503

A case study of multi-seam coal mine entry stability analysis with strength reduction method.

PubMed

Tulu, Ihsan Berk; Esterhuizen, Gabriel S; Klemetti, Ted; Murphy, Michael M; Sumner, James; Sloan, Michael

2016-03-01

In this paper, the advantage of using numerical models with the strength reduction method (SRM) to evaluate entry stability in complex multiple-seam conditions is demonstrated. A coal mine under variable topography from the Central Appalachian region is used as a case study. At this mine, unexpected roof conditions were encountered during development below previously mined panels. Stress mapping and observation of ground conditions were used to quantify the success of entry support systems in three room-and-pillar panels. Numerical model analyses were initially conducted to estimate the stresses induced by the multiple-seam mining at the locations of the affected entries. The SRM was used to quantify the stability factor of the supported roof of the entries at selected locations. The SRM-calculated stability factors were compared with observations made during the site visits, and the results demonstrate that the SRM adequately identifies the unexpected roof conditions in this complex case. It is concluded that the SRM can be used to effectively evaluate the likely success of roof supports and the stability condition of entries in coal mines.

30 CFR 75.208 - Warning devices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Warning devices. 75.208 Section 75.208 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.208 Warning devices. Except during the installation of roof supports, the end of permanent roof support shall be posted with a readily visible warning...

30 CFR 75.208 - Warning devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Warning devices. 75.208 Section 75.208 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.208 Warning devices. Except during the installation of roof supports, the end of permanent roof support shall be posted with a readily visible warning...

30 CFR 75.208 - Warning devices.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Warning devices. 75.208 Section 75.208 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.208 Warning devices. Except during the installation of roof supports, the end of permanent roof support shall be posted with a readily visible warning...

30 CFR 75.208 - Warning devices.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Warning devices. 75.208 Section 75.208 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.208 Warning devices. Except during the installation of roof supports, the end of permanent roof support shall be posted with a readily visible warning...

30 CFR 75.208 - Warning devices.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Warning devices. 75.208 Section 75.208 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.208 Warning devices. Except during the installation of roof supports, the end of permanent roof support shall be posted with a readily visible warning...

Hydrological performance of an extensive green roof: a case study from the central Europe (Bustehrad, Czech Republic)

NASA Astrophysics Data System (ADS)

Tománková, Klára; Sněhota, Michal; Jelínková, Vladimíra

2016-04-01

Extensive green roofs with a thin growing medium require minimal maintenance, and in general no irrigation. The proper functioning of such systems rests with their structural constituents, especially with the substrate used for planting. An extensive green roof with poorly developed vegetation and with a soil layer of a maximum thickness of 5 cm mixed with local stripped topsoil with crushed bricks and green waste was studied with respect to the hydrological behavior. The substrate classified as loam comprises a significant proportion of very fine particles and thus it is prone to clogging up of soil pores and forming of fissures on the surface. The green roof studied is well equipped for measuring meteorological data including air temperature, wind speed and direction, net radiation, relative humidity, and rainfall intensity. The meteorological information on the site is completed by soil temperature measurement. The 12 m long transect is equipped with eight time domain reflectometry probes (TDR) to monitor soil water content. Soil physical properties (bulk density, porosity, grain size distribution) and soil hydraulic characteristics (soil water retention curve) were obtained. The numerical modeling of transient soil water movement in the green roof substrate was performed using a two-dimensional model based on the Richards' equation. Results were compared with the soil water content data acquired. Six alternative scenarios were formulated to discuss possible improvement of green roof functioning and four selected scenarios were simulated. The study helped us to improve our understanding of the flow processes through the green roof soil system under study. The alternative scenario simulations allowed hydrological assessment of roof construction amendments. 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.

BIPV: a real-time building performance study for a roof-integrated facility

NASA Astrophysics Data System (ADS)

Aaditya, Gayathri; Mani, Monto

2018-03-01

Building integrated photovoltaic system (BIPV) is a photovoltaic (PV) integration that generates energy and serves as a building envelope. A building element (e.g. roof and wall) is based on its functional performance, which could include structure, durability, maintenance, weathering, thermal insulation, acoustics, and so on. The present paper discusses the suitability of PV as a building element in terms of thermal performance based on a case study of a 5.25 kWp roof-integrated BIPV system in tropical regions. Performance of PV has been compared with conventional construction materials and various scenarios have been simulated to understand the impact on occupant comfort levels. In the current case study, PV as a roofing material has been shown to cause significant thermal discomfort to the occupants. The study has been based on real-time data monitoring supported by computer-based building simulation model.

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.

Apparatus and method for mounting photovoltaic power generating systems on buildings

DOEpatents

Russell, Miles Clayton [Lincoln, MA

2008-10-14

Rectangular PV modules (6) are mounted on a building roof (4) by mounting stands that are distributed in rows and columns. Each stand comprises a base plate (10) that rests on the building roof (4) and first and second brackets (12, 14) of different height attached to opposite ends of the base plate (10). Each bracket (12, 14) has dual members for supporting two different PV modules (6), and each PV module (6) has a mounting pin (84) adjacent to each of its four corners. Each module (6) is supported by attachment of two of its mounting pins (84) to different first brackets (12), whereby the modules (6) and their supporting stands are able to resist uplift forces resulting from high velocity winds without the base plates (10) being physically attached to the supporting roof structure (4). Preferably the second brackets (14) have a telescoping construction that permits their effective height to vary from less than to substantially the same as that of the first brackets (12).

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.

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)

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.

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.

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.

Calculation of parameters of combined frame and roof bolting

NASA Astrophysics Data System (ADS)

Ivanov, S. I.; Titov, N. V.; Privalov, A. A.; Trunov, I. T.; Sarychev, V. I.

2017-10-01

The paper presents the method of calculation of the combined frame and roof bolting. Recommendations on providing joint operation of roof bolting with steel support frames are given. Graphs for determining standard rock movement, as well as for defining proof load on the yielding support, were developed.

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)

Characteristics of the Roof Behaviors and Mine Pressure Manifestations During the Mining of Steep Coal Seam

NASA Astrophysics Data System (ADS)

Hong-Sheng, Tu; Shi-Hao, Tu; Cun, Zhang; Lei, Zhang; Xiao-Gang, Zhang

2017-12-01

A steep seam similar simulation system was developed based on the geological conditions of a steep coal seam in the Xintie Coal Mine. Basing on similar simulation, together with theoretical analysis and field measurement, an in-depth study was conducted to characterize the fracture and stability of the roof of steep working face and calculate the width of the region backfilled with gangue in the goaf. The results showed that, as mining progressed, the immediate roof of the steep face fell upon the goaf and backfilled its lower part due to gravity. As a result, the roof in the lower part had higher stability than the roof in the upper part of the working face. The deformation and fracture of main roof mainly occurred in the upper part of the working face; the fractured main roof then formed a "voussoir beam" structure in the strata's dip direction, which was subjected to the slip- and deformation-induced instability. The stability analysis indicated that, when the dip angle increased, the rock masses had greater capacity to withstand slip-induced instability but smaller capacity to withstand deformation-induced instability. Finally, the field measurement of the forces exerted on the hydraulic supports proved the characteristics of the roof's behaviors during the mining of a steep seam.

Coupled Finite Volume and Finite Element Method Analysis of a Complex Large-Span Roof Structure

NASA Astrophysics Data System (ADS)

Szafran, J.; Juszczyk, K.; Kamiński, M.

2017-12-01

The main goal of this paper is to present coupled Computational Fluid Dynamics and structural analysis for the precise determination of wind impact on internal forces and deformations of structural elements of a longspan roof structure. The Finite Volume Method (FVM) serves for a solution of the fluid flow problem to model the air flow around the structure, whose results are applied in turn as the boundary tractions in the Finite Element Method problem structural solution for the linear elastostatics with small deformations. The first part is carried out with the use of ANSYS 15.0 computer system, whereas the FEM system Robot supports stress analysis in particular roof members. A comparison of the wind pressure distribution throughout the roof surface shows some differences with respect to that available in the engineering designing codes like Eurocode, which deserves separate further numerical studies. Coupling of these two separate numerical techniques appears to be promising in view of future computational models of stochastic nature in large scale structural systems due to the stochastic perturbation method.

Roofing Source File.

ERIC Educational Resources Information Center

American School & University, 1994

1994-01-01

Presents a resource guide for identifying, selecting, and specifying educational roofing systems. Explores the various types of roofing systems considered for most schools and describes how to select a roofing contractor and consultant. A roofing retrofit check list and roofing specification chart are provided. (GR)

Mapping the Green Infrastructure potential - and it's water-energy impacts on New York City roof Tops

NASA Astrophysics Data System (ADS)

Engström, Rebecka; Destouni, Georgia; Howells, Mark

2017-04-01

Green Roofs have the potential to provide multiple services in cities. Besides acting as carbon sinks, providing noise reduction and decreasing air pollution - without requiring any additional "land-use" in a city (only roof-use), green roofs have a quantifiable potential to reduce direct and indirect energy and water use. They enhance the insulating capacity of a conventional residential roof and thereby decrease both cooling demands in summer and heating demands in winter. The former is further mitigated by the cooling effect of evapotranspiration from the roofs In New York City green roofs are additionally a valuable component of reducing "combined sewer overflows", as these roofs can retain storm water. This can improve water quality in the city's rivers as well as decrease the total volume of water treated in the city's wastewater treatment plants, thereby indirectly reduce energy demands. The impacts of green roofs on NYC's water-energy nexus has been initially studied (Engström et. al, forthcoming). The present study expands that work to more comprehensively investigate the potential of this type of nature-based solution in a dense city. By employing Geographical Information Systems analysis, the roof top area of New York City is analysed and roof space suitable for green roofs of varying types (ranging from extensive to intensive) are mapped and quantified. The total green roof area is then connected with estimates of potential water-energy benefits (and costs) of each type of green roof. The results indicate where green roofs can be beneficially installed throughout the city, and quantifies the related impacts on both water and energy use. These outputs can provide policy makers with valuable support when facing investment decisions in green infrastructure, in a city where there is great interest for these types of nature-based solutions.

49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

30 CFR 75.209 - Automated Temporary Roof Support (ATRS) systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... paragraph shall be met according to the following schedule: (1) All new machines ordered after March 28... the left, right or beyond the ATRS system, shall not exceed 5 feet. (e) Each ATRS system shall meet...

30 CFR 75.209 - Automated Temporary Roof Support (ATRS) systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... paragraph shall be met according to the following schedule: (1) All new machines ordered after March 28... the left, right or beyond the ATRS system, shall not exceed 5 feet. (e) Each ATRS system shall meet...

Thermal Performance of Vegetative Roofing Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Desjarlais, Andre Omer; Zaltash, Abdolreza; Atchley, Jerald Allen

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.more » 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% in the mixed climate of East Tennessee. It should be noted that these values are climate dependent. Vegetative roofs also reduced the temperature (heat exposure) and temperature fluctuations (thermal stress) experienced by the membrane. In the cooling season of East Tennessee, the average peak temperature of the 4-inch and tray systems was found to be approximately 94 F cooler than the control black roofing system. The average temperature fluctuations at the membrane for the 4-inch and tray systems were found to be approximately 10 F compared to 125 F for black and 64 F for white systems. As expected, the 8-inch vegetative roof had the lowest fluctuations at approximately 2 F. Future work will include modeling of the energy performance of vegetative roof panels in the test climate of East Tennessee. The validated model then will be used to predict energy use in roofs with different insulation levels and in climates different from the test climate.« less

Development of the trickle roof cooling and heating system: Experimental plan

NASA Astrophysics Data System (ADS)

Haves, P.; Jankovic, T.; Doderer, E.

1982-07-01

A passive system applicable both to retrofit and new construction was developed. This system (the trickle roof system) dissipates heat from a thin film of water flowing over the roof. A small scale trickle roof system dissipator was tested at Trinity University under a range of ambient conditions and operating configurations. The results suggest that trickle roof systems should have comparable performance to roof pond systems. Provided is a review of the trickle roof system concept, several possible configurations, and the benefits the systems can provide. Test module experiments And results are presented in detail. The requirements for full scale testing are discussed and a plan is outlined using the two identical residential scale passive test facility buildings at Trinity University, San Antonio, Texas. Full scale experimental results would be used to validate computer algorithms, provide system optimization, and produce a nationwide performance assessment and design guidelines. This would provide industry with the information necessary to determine the commerical potential of the trickle roof system.

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 the winter-time penalty, and the net benefit from adopting white roof technology in Portland is small. That said, there are other potential benefits of white roofing such as impact on urban heat islands and roof life that must also be considered.

Assessing the Performance of Large Scale Green Roofs and Their Impact on the Urban Microclimate

NASA Astrophysics Data System (ADS)

Smalls-Mantey, L.; Foti, R.; Montalto, F. A.

2015-12-01

In ultra-urban environments green roofs offer a feasible solution to add green infrastructure (GI) in neighborhoods where space is limited. Green roofs offer the typical advantages of urban GI such as stormwater reduction and management while providing direct benefits to the buildings on which they are installed through thermal protection and mitigation of temperature fluctuations. At 6.8 acres, the Jacob K. Javits Convention Center (JJCC) in New York City, hosts the second largest green roof in the United States. Since its installation in August 2013, the Sustainable Water Resource (SWRE) Laboratory at Drexel University has monitored the climate on and around the green roof by means of four weather stations situated on various roof and ground locations. Using two years of fine scale climatic data collected at the JJCC, this study explores the energy balance of a large scale green roof system. Temperature, radiation, evapotranspiration and wind profiles pre- and post- installation of the JJCC green roof were analyzed and compared across monitored locations, with the goal of identifying the impact of the green roof on the building and urban micro-climate. Our findings indicate that the presence of the green roof, not only altered the climatic conditions above the JJCC, but also had a measurable impact on the climatic profile of the areas immediately surrounding it. Furthermore, as a result of the mitigation of roof temperature fluctuations and of the cooling provided during warmer months, an improvement of the building thermal efficiency was contextually observed. Such findings support the installation of GI as an effective practice in urban settings and important in the discussion of key issues including energy conservation measures, carbon emission reductions and the mitigation of urban heat islands.

Specifying, Installing and Maintaining Built-Up and Modified Bitumen Roofing Systems.

ERIC Educational Resources Information Center

Hobson, Joseph W.

2000-01-01

Examines built-up, modified bitumen, and hybrid combinations of the two roofing systems and offers advise on how to assure high- quality performance and durability when using them. Included is a glossary of commercial roofing terms and asphalt roofing resources to aid in making decisions on roofing and systems product selection. (GR)

Other Fabric Structures

NASA Technical Reports Server (NTRS)

1985-01-01

There are two kinds of fabric structures - tension, supported by cables and pylons, and those supported by air pressure within an enclosed fabric envelope. They are becoming increasingly popular with architects, engineers, etc., because of their aesthetic appeal, low cost and maintenance, energy efficiency and good space utilization. The Structo-Fab roof weighs only 1/30 as much as a conventional roof of that size. Giant fans are used to blow air into the envelope between the roof's outer membrane and its inner liner automatically maintaining the pressure differential necessary for roof rigidity.

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 facilitate the adoption and appropriate utilization of green roof technologies and make it possible to account for green roof benefits in energy codes and related energy efficiency standards and rating systems such as LEED.

KSC-2013-1783

NASA Image and Video Library

2013-03-05

CAPE CANAVERAL, Fla. – A telemetry antenna and tracker camera is attached to the roof of the Launch Control Center, or LCC, in Launch Complex 39 at NASA's Kennedy Space Center in Florida. This antenna and camera system is the first of three to be installed on the LCC roof for the Radio Frequency and Telemetry Station RFTS, which will be used to monitor radio frequency communications from a launch vehicle at Launch Pad 39A or B as well as provide radio frequency relay for a launch vehicle in the Vehicle Assembly Building. The RFTS replaces the shuttle-era communications and tracking labs at Kennedy. The modern RFTS checkout station is designed to primarily support NASA's Space Launch System, or SLS, and Orion spacecraft, but can support multi-user radio frequency tests as the space center transitions to support a variety of rockets and spacecraft. For more information on the modernization efforts at Kennedy, visit the Ground Systems Development and Operations, or GSDO, website at http://go.nasa.gov/groundsystems. Photo credit: NASA/Jim Grossmann

DETAIL, NORTHEAST POST SUPPORTING SHED PORCH ROOF ON NORTH FACADE; ...

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

DETAIL, NORTHEAST POST SUPPORTING SHED PORCH ROOF ON NORTH FACADE; VIEW TO EAST - Fort Bragg, Noncommissioned Officers' Service Club, Guest House Building, South of Butner Road, Fayetteville, Cumberland County, NC

Study on the new technology of removing gangue and retaining roadway in complicated roof condition

NASA Astrophysics Data System (ADS)

Chen, Yanhao; Jiang, Cong

2018-04-01

This article in view of the complex roof conditions was carried on study about the new technology of removing gangue and retaining roadway, and tells a method of progressive reinforced concrete wall segment with gangue to keep the roadway, the roadway beside the support system is mainly composed of the lining, waste rock wall and the outer wall, the wall and the outer wall of concrete material width to build the strength of the progressive type filling body, waste rock wall with woven bag with waste rock assembled, paragraphs geological survey on the actual distance should be based on working face. This method relies on the interior of the gangue wall to make the pressure control and allow the roof to sink. In this paper, the finite deformation control of the roof is realized by the gangue wall and the high strength filling body. This method has the characteristics of low entry cost, good forming of roadway, high security and good stability, and can be applied to complex geological conditions such as hard roof.

Cost Effectiveness of Precast Reinforced Concrete Roof Slabs

NASA Astrophysics Data System (ADS)

Parskiy, N. D.; Molodtsov, M. V.; Molodtsova, V. E.

2017-11-01

Engineers always seek to free interior space from intermediate supporting elements. Nowadays plants, being at the forefront of technology, produce a new generation of exclusive patented prefabricated reinforced concrete elements with a high load-bearing capacity, excellent heat resistance characteristics combined with the aesthetics and beauty. It is a system of Seagull Gabbiano prestressed roof slabs for the spans of 12m - 40m. The article shows the advantages of the Seagull slabs over conventional precast reinforced concrete and metal roof trusses. It also gives the analysis of the technical and economic indices of design and construction of a building with the Seagull slabs depending on the size of spans to cover. The use of structural systems with increased spans allows for the modern buildings and structures of prefabricated reinforced concrete with enhanced functionality and aesthetics alongside with a wide range of planning solutions.

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)

24 CFR 3280.402 - Test procedure for roof trusses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... trusses that are supported at the ends and support design loads. Where roof trusses act as support for... shall be spaced at the design spacing and shall be mounted on solid support accurately positioned to give the required clear span distance (L) as specified in the design. The top and bottom chords shall...

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 travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

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 travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

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 travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

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 travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

30 CFR 75.202 - Protection from falls of roof, face and ribs.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 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 travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

A steering law for a roof-type configuration for a single-gimbal control moment gyro system

NASA Technical Reports Server (NTRS)

Yoshikawa, T.

1974-01-01

Single-Gimbal Control Moment Gyro (SGCMG) systems have been investigated for attitude control of the Large Space Telescope (LST) and the High Energy Astronomy Observatory (HEAO). However, various proposed steering laws for the SGCMG systems thus far have some defects because of singular states of the system. In this report, a steering law for a roof-type SGCMG system is proposed which is based on a new momentum distribution scheme that makes all the singular states unstable. This momentum distribution scheme is formulated by a treatment of the system as a sampled-data system. From analytical considerations, it is shown that this steering law gives control performance which is satisfactory for practical applications. Results of the preliminary computer simulation entirely support this premise.

Solare Cell Roof Tile And Method Of Forming Same

DOEpatents

Hanoka, Jack I.; Real, Markus

1999-11-16

A solar cell roof tile includes a front support layer, a transparent encapsulant layer, a plurality of interconnected solar cells and a backskin layer. The front support layer is formed of light transmitting material and has first and second surfaces. The transparent encapsulant layer is disposed adjacent the second surface of the front support layer. The interconnected solar cells has a first surface disposed adjacent the transparent encapsulant layer. The backskin layer has a first surface disposed adjacent a second surface of the interconnected solar cells, wherein a portion of the backskin layer wraps around and contacts the first surface of the front support layer to form the border region. A portion of the border region has an extended width. The solar cell roof tile may have stand-offs disposed on the extended width border region for providing vertical spacing with respect to an adjacent solar cell roof tile.

Roofing research and standards development: Fourth volume. ASTM special technical publication 1349

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wallace, T.J.; Rossiter, W.J. Jr.

1999-07-01

As the roofing industry has stabilized, a broad variety of roof systems have found general acceptance by the building owners, architects, engineers, contractors, and others who select and install roofs. These roof systems include those based on conventional built-up membranes using glass and synthetic reinforcements, synthetic polymeric membranes using elastomers and thermoplastics, polymer-modified membranes, and sprayed polyurethane foam. ASTM Committee D8 on Roofing, Waterproofing, and Bituminous Materials has contributed significantly in many important ways to the roofing community's stabilization including issuing standard specifications to assist consumers in the selection and use of these systems. This is not surprising, as itmore » has always been among the purpose of D8 to provide standards to assist in the selection and use of low-sloped and steep roofing. The Committee's scope includes development of standards associated with application, inspection, maintenance, and analyses. Some of the issues facing the roofing community today--for example, enhanced system durability, better methods of material characterization, environmental impact, recycling of materials and systems, industry conversation to the S.I. system metric--readily fall within D8's scope. The availability of sound standard can contribute to the resolution of many of these issues.« less

Prevention of residential roof fires by use of a class "A" fire rated roof system.

PubMed

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

2004-01-01

Because residential roof fires remain a life-threatening danger to residential homeowners in the United States, we describe in detail 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. This Class A system should comply with the test requirements for fire resistance of roof coverings, as outlined in UL 790 or in ASTM International (ASTM) E-108. Both the Asphalt Roofing Manufacturer's Association (ARMA) and the National Roofing Contractors Association (NRCA) have set up guidelines for selecting a new roof for the homeowner. Class A, fiber-glass-based asphalt roofing shingles represent an overwhelming share of the United States residential roofing market, and, as such, the Class A rated roofing system remains an excellent alternative to wood shingles and shakes. Fortunately, the Class A fire rating is available for certain wood shingle products that incorporate a factory-applied, fire resistant treatment. However, in this circumstance, wood products labeled as Class B shakes or shingles must be installed over spaced or solid sheathing that have been covered either with one layer of 1/4 in. (6.4 mm) thick noncombustible roof board, or with one layer of minimum 72-lb. fiber-glass-based mineral surfaced cap sheet, or with another specialty roofing sheet to obtain the Class A fire rating. Clay, tile, slate, and metal have been assigned Class A fire ratings in the codes (but often without testing). These alternative roofing materials are often considerably more expensive. Proper application, ventilation, and insulation of roofing systems are required to prevent heat and moisture buildup in the attic, which can damage the roofing system, making it more susceptible to water leakage as well as ignition in the event of a fire. The NRCA has devised excellent recommendations for the homeowner to prequalify the contractor. In addition, a warranty for any new roofing material is important for the homeowner to ensure that the roofing can be repaired by the contractor or manufacturer during the specified warranty period, in case of contractor error or a manufacturing defect. In addition, the homeowner should ensure that the warranty is transferable to any future owner of the home to allow the buyer to have the same warranty benefits as the original owner. The State of California has mandated strict roofing requirements to prevent residential fires. In the absence of this legislation in other states, the homeowner must follow the guidelines outlined in this collective review to ensure that a roofing system with Class A fire protection is installed. Other fire safety precautions that should also be considered mandatory are to include smoke alarms, escape plans, and retrofit fire sprinklers.

30 CFR 75.206 - Conventional roof support.

Code of Federal Regulations, 2010 CFR

2010-07-01

... materials are used as the only means of support— (1) The width of any opening shall not exceed 20 feet; (2) The spacing of roadway roof support shall not exceed 5 feet; (3)(i) Supports shall be installed to within 5 feet of the uncut face; (ii) When supports nearest the face must be removed to facilitate the...

30 CFR 75.206 - Conventional roof support.

Code of Federal Regulations, 2011 CFR

2011-07-01

... materials are used as the only means of support— (1) The width of any opening shall not exceed 20 feet; (2) The spacing of roadway roof support shall not exceed 5 feet; (3)(i) Supports shall be installed to within 5 feet of the uncut face; (ii) When supports nearest the face must be removed to facilitate the...

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...

30 CFR 75.215 - Longwall mining systems.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Longwall mining systems. 75.215 Section 75.215... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.215 Longwall mining systems. For each... a safe travelway out of the section through the tailgate side of the longwall; and (b) The...

30 CFR 75.215 - Longwall mining systems.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Longwall mining systems. 75.215 Section 75.215... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.215 Longwall mining systems. For each... a safe travelway out of the section through the tailgate side of the longwall; and (b) The...

30 CFR 75.215 - Longwall mining systems.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Longwall mining systems. 75.215 Section 75.215... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.215 Longwall mining systems. For each... a safe travelway out of the section through the tailgate side of the longwall; and (b) The...

Roofer: An Engineered Management System (EMS) for Bituminous Built-Up Roofs

DTIC Science & Technology

1989-12-01

individual roof projects. Figure 1 shows an example of a filing sequence for a typical recordkceping system. The file should contain a Building Folder ...for each building and a Roof Section Foldcr for each roof section on the building. Building Folder The Building Folder should contain a completed...should also be kept in the building folder , or if they are kept elsewhere, their location should be stated in the folder . Roof Section Folder A Roof

Building-integrated photovoltaics: A case study

NASA Astrophysics Data System (ADS)

Kiss, G.; Kinkead, J.; Raman, M.

1995-03-01

In 1992, Kiss Cathcart Anders Architects performed a study for NREL on Building-Integrated Photovoltaics (BIPV) issues as seen from the perspective of the building community. In general, the purpose of the study was to list major issues and potential applications; by it's nature it asked more questions than it answered. This second phase study was to produce quantitative data on the performance of specific BIPV systems. Only roof systems are evaluated. The energy performance, construction cost and simple payback for five different BIPV roof options are evaluated in six different locations: Oakland, New York, Miami, Phoenix, Chicago, and Cincinnati. The roof options evaluated include the following: single-glazed PV roof using glass-substrate PVs; double-glazed PV roof with insulating PV modules; ballasted roof-mounted system; sawtooth light monitor roof with indirect north daylighting; sawtooth roof with north light and active heat recovery.

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

Evaluation on Thermal Behavior of a Green Roof Retrofit System Installed on Experimental Building in Composite Climate of Roorkee, India

NASA Astrophysics Data System (ADS)

Kumar, Ashok; Deoliya, Rajesh; Chani, P. S.

2015-12-01

Green roofs not only provide cooling by shading, but also by transpiration of water through the stomata. However, the evidence for green roofs providing significant air cooling remains limited. No literature investigates the thermal performance of prefab brick panel roofing technology with green roof. Hence, the aim of this research is to investigate the thermal behavior of an experimental room, built at CSIR-Central Building Research Institute (CBRI) campus, Roorkee, India using such roofing technology during May 2013. The study also explores the feasibility of green roof with grass carpets that require minimum irrigation, to assess the expected indoor thermal comfort improvements by doing real-time experimental studies. The results show that the proposed green roof system is suitable for reducing the energy demand for space cooling during hot summer, without worsening the winter energy performance. The cost of proposed retrofit system is about Rs. 1075 per m2. Therefore, green roofs can be used efficiently in retrofitting existing buildings in India to improve the micro-climate on building roofs and roof insulation, where the additional load carrying capacity of buildings is about 100-130 kg/m2.

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.

Building-integrated photovoltaics: A case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kiss, G.; Kinkead, J.; Raman, M.

1995-03-01

In 1992, Kiss Cathcart Anders Architects performed a study for NREL on Building-Integrated Photovoltaics (BIPV) issues as seen from the perspective of the building community. In general, the purpose of the study was to list major issues and potential applications; by it`s nature it asked more questions than it answered. This second phase study was to produce quantitative data on the performance of specific BIPV systems. Only roof systems are evaluated. The energy performance, construction cost and simple payback for five different BIPV roof options are evaluated in six different locations: Oakland, New York, Miami, Phoenix, Chicago, and Cincinnati. Themore » roof options evaluated include the following: single-glazed PV roof using glass-substrate PVs; double-glazed PV roof with insulating PV modules; ballasted roof-mounted system; sawtooth light monitor roof with indirect north daylighting; sawtooth roof with north light and active heat recovery.« less

KSC-2013-1782

NASA Image and Video Library

2013-03-05

CAPE CANAVERAL, Fla. – With the help of a crane, a worker helps guide a parabolic telemetry antenna and tracker camera to the roof of the Launch Control Center, or LCC, in Launch Complex 39 at NASA's Kennedy Space Center in Florida. This antenna and camera system is the first of three that will be installed on the LCC roof for the Radio Frequency and Telemetry Station RFTS, which will be used to monitor radio frequency communications from a launch vehicle at Launch Pad 39A or B as well as provide radio frequency relay for a launch vehicle in the Vehicle Assembly Building. The RFTS replaces the shuttle-era communications and tracking labs at Kennedy. The modern RFTS checkout station is designed to primarily support NASA's Space Launch System, or SLS, and Orion spacecraft, but can support multi-user radio frequency tests as the space center transitions to support a variety of rockets and spacecraft. For more information on the modernization efforts at Kennedy, visit the Ground Systems Development and Operations, or GSDO, website at http://go.nasa.gov/groundsystems. Photo credit: NASA/Jim Grossmann

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

PROCESS WATER BUILDING, TRA605. FLOOR AND ROOF PLANS FOR SECOND ...

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

PROCESS WATER BUILDING, TRA-605. FLOOR AND ROOF PLANS FOR SECOND FLOOR. DETAILS OF CONCRETE ROOF SLABS. FLASH EVAPORATOR SUPPORTS AND PIPE OPENINGS TO TANKS BELOW. NOTE SPECIFIES THAT EQUIPMENT IS TO BE INSTALLED BEFORE ERECTION OF ROOF AND WALLS. BLAW-KNOX 3150-805-4, 1/1951. INL INDEX NO. 531-0605-62-098-100660, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Advantages of a Vertical High-Resolution Distributed-Temperature-Sensing System Used to Evaluate the Thermal Behavior of Green Roofs

NASA Astrophysics Data System (ADS)

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

2015-12-01

Technological innovations used for sustainable urban development, green roofs offer a range of benefits, including reduced heat island effect, rooftop runoff, roof surface temperatures, energy consumption, and noise levels inside buildings, as well as increased urban biodiversity. Green roofs feature layered construction, with the most important layers being the vegetation and the substrate layers located above the traditional roof. These layers provide both insulation and warm season cooling by latent heat flux, reducing the thermal load to the building. To understand and improve the processes driving this thermal energy reduction, it is important to observe the thermal dynamics of a green roof at the appropriate spatial and temporal scales. Traditionally, to observe the thermal behavior of green roofs, a series of thermocouples have been installed at discrete depths within the layers of the roof. Here, we present a vertical high-resolution distributed-temperature-sensing (DTS) system installed in different green roof modules of the Laboratory of Vegetated Infrastructure for Buildings (LIVE -its acronym in Spanish) of the Pontifical Catholic University of Chile. This DTS system allows near-continuous measurement of the thermal profile at spatial and temporal resolutions of approximately 1 cm and 30 s, respectively. In this investigation, the temperature observations from the DTS system are compared with the measurements of a series of thermocouples installed in the green roofs. This comparison makes it possible to assess the value of thermal observations at better spatial and temporal resolutions. We show that the errors associated with lower resolution observations (i.e., from the thermocouples) are propagated in the calculations of the heat fluxes through the different layers of the green roof. Our results highlight the value of having a vertical high-resolution DTS system to observe the thermal dynamics in green roofs.

Automatic Coal-Mining System

NASA Technical Reports Server (NTRS)

Collins, E. R., Jr.

1985-01-01

Coal cutting and removal done with minimal hazard to people. Automatic coal mine cutting, transport and roof-support movement all done by automatic machinery. Exposure of people to hazardous conditions reduced to inspection tours, maintenance, repair, and possibly entry mining.

LIGHTWEIGHT GREEN ROOF SYSTEMS

EPA Science Inventory

Applying a Lightweight Green Roof System to a building can achieve in managing storm water runoff, decreasing heat gain, yielding energy savings, and mitigating the heat island effect. Currently, Most green roof systems are considerably heavy and require structural reinforceme...

Flexible Answers.

ERIC Educational Resources Information Center

Seeley, James

1997-01-01

Describes how schools are investigating single-ply roofing systems for new and retrofit construction. Discusses some of the considerations in seaming together a single-ply roof, steps in choosing roofing material and a roofing contractor, warranty advice, and the importance of keeping records on roof maintenance. (RJM)

Law of Strata Pressure Behavior in Shallow Coal Seam

NASA Astrophysics Data System (ADS)

Zhao, Jian; Liu, Leibin; Zheng, Zhiyang

2018-02-01

The law of strata pressure behavior in shallow coal seam is analyzed, according to the load data of Jinjie Coal Mine 31109 working face hydraulic supports. The first weighting distance of main roof is 80 m, and the periodic weighting distance of main roof is about 20 m. And according to the load data in the middle and both ends of the working face, the working resistance of hydraulic supports and the setting load are a bit small, so they couldn’t meet the needs of supporting roof. Then, the front abutment pressure of working face is analyzed by numerical simulation. It does not only explain the reason that the load is too big, but also explains the reason that the strata pressure behavior in shallow coal seam is serious. The length of undamaged main roof rock beam verifies the correctness of the periodic weighting distance.

Johnston Avenue Solar Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schrayer, David

2017-08-22

DOE awarded funds to support a demonstration project to illustrate how access to solar power and green roof systems could improve building performance and long-term outcomes for the building owner and multiple nonprofit tenants housed in the building. Since being placed in service the solar PV system has saved approximately $1,000 per month in energy costs. The green roof has added to this benefit by naturally cooling the building and has helped reduce local road flooding by retaining storm water. These elements have improved the quality of life in the low-income community in which the building is located by allowingmore » social service organizations to focus more of their resources on programs and job creation.« less

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)

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.

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

Mine roof driller-bolter apparatus and method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hibbard, G.A.; Lumbra, R.C.; Morrison, W.D.

1983-12-13

An apparatus for bolting the roof of an underground mine is disclosed comprising a mobile frame, a boom extending from the frame and a housing provided at the end of the frame. The housing supports an upwardly extending stinger, a drilling mechanism including a drill centralizer having a central bore therethrough and a passageway in communication with the central bore, a device for delivering a container of roof bolting anchoring media through the passageway and through the drill centralizer and into a drilled hole, a device for indexing a roof bolt into alignment with the drilled hole and a spinnermore » for driving the roof bolt into the drilled hole. The present invention also provides a method for bolting the roof of an underground mine comprising the steps of stinging a housing against the roof of the mine, moving a drill centralizer into communication with the roof and drilling a hole in the roof. Without retracting the drill centralizer from communication with the roof, a container of roof bolt anchoring media is delivered through the centralizer and into the drilled hole. The drill centralizer is thereafter retracted and the housing is moved to align a roof bolt with a drilled hole. Then the roof bolt is driven into the drilled hole and the bolt anchoring media sets around the bolt.« less

Molded Concrete Center Mine Wall

NASA Technical Reports Server (NTRS)

Lewis, E. V.

1987-01-01

Proposed semiautomatic system forms concrete-foam wall along middle of coal-mine passage. Wall helps support roof and divides passage into two conduits needed for ventilation of coal face. Mobile mold and concrete-foam generator form sections of wall in place.

Demonstration of Three Corrosion-Resistant Sustainable Roofing Systems

DTIC Science & Technology

2013-06-01

will significantly im- prove upon the performance of the original roofing systems . Improvement of energy efficiency, drainage , and other attributes...Sustainable Roofing Systems Final Report on Project F08-AR02 Co ns tr uc tio n En gi ne er in g R es ea rc h La bo ra to ry David M. Bailey...CERL TR-13-7 June 2013 Demonstration of Three Corrosion-Resistant Sustainable Roofing Systems Final Report on Project F08-AR02 David M. Bailey

GARAGE EXTERIOR EAST SIDE AND REAR SHOWING PIER SUPPORTS UNDER ...

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

GARAGE EXTERIOR EAST SIDE AND REAR SHOWING PIER SUPPORTS UNDER SHED-ROOFED REAR STORAGE COMPARTMENT, ASBESTOS SIDING OVER ORIGINAL WOOD SIDING, AND SINGLE CASEMENT WINDOW OVER REAR STORAGE COMPARTMENT. VIEW TO NORTHWEST - Big Creek Hydroelectric System, Big Creek Town, Operator House Garage, Orchard Avenue south of Huntington Lake Road, Big Creek, Fresno County, CA

Development of spectral indices for roofing material condition status detection using field spectroscopy and WorldView-3 data

NASA Astrophysics Data System (ADS)

Samsudin, Sarah Hanim; Shafri, Helmi Z. M.; Hamedianfar, Alireza

2016-04-01

Status observations of roofing material degradation are constantly evolving due to urban feature heterogeneities. Although advanced classification techniques have been introduced to improve within-class impervious surface classifications, these techniques involve complex processing and high computation times. This study integrates field spectroscopy and satellite multispectral remote sensing data to generate degradation status maps of concrete and metal roofing materials. Field spectroscopy data were used as bases for selecting suitable bands for spectral index development because of the limited number of multispectral bands. Mapping methods for roof degradation status were established for metal and concrete roofing materials by developing the normalized difference concrete condition index (NDCCI) and the normalized difference metal condition index (NDMCI). Results indicate that the accuracies achieved using the spectral indices are higher than those obtained using supervised pixel-based classification. The NDCCI generated an accuracy of 84.44%, whereas the support vector machine (SVM) approach yielded an accuracy of 73.06%. The NDMCI obtained an accuracy of 94.17% compared with 62.5% for the SVM approach. These findings support the suitability of the developed spectral index methods for determining roof degradation statuses from satellite observations in heterogeneous urban environments.

Simulation of green roof runoff under different substrate depths and vegetation covers by coupling a simple conceptual and a physically based hydrological model.

PubMed

Soulis, Konstantinos X; Valiantzas, John D; Ntoulas, Nikolaos; Kargas, George; Nektarios, Panayiotis A

2017-09-15

In spite of the well-known green roof benefits, their widespread adoption in the management practices of urban drainage systems requires the use of adequate analytical and modelling tools. In the current study, green roof runoff modeling was accomplished by developing, testing, and jointly using a simple conceptual model and a physically based numerical simulation model utilizing HYDRUS-1D software. The use of such an approach combines the advantages of the conceptual model, namely simplicity, low computational requirements, and ability to be easily integrated in decision support tools with the capacity of the physically based simulation model to be easily transferred in conditions and locations other than those used for calibrating and validating it. The proposed approach was evaluated with an experimental dataset that included various green roof covers (either succulent plants - Sedum sediforme, or xerophytic plants - Origanum onites, or bare substrate without any vegetation) and two substrate depths (either 8 cm or 16 cm). Both the physically based and the conceptual models matched very closely the observed hydrographs. In general, the conceptual model performed better than the physically based simulation model but the overall performance of both models was sufficient in most cases as it is revealed by the Nash-Sutcliffe Efficiency index which was generally greater than 0.70. Finally, it was showcased how a physically based and a simple conceptual model can be jointly used to allow the use of the simple conceptual model for a wider set of conditions than the available experimental data and in order to support green roof design. Copyright © 2017 Elsevier Ltd. All rights reserved.

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)

Conduction cooled tube supports

DOEpatents

Worley, Arthur C.; Becht, IV, Charles

1984-01-01

In boilers, process tubes are suspended by means of support studs that are in thermal contact with and attached to the metal roof casing of the boiler and the upper bend portions of the process tubes. The support studs are sufficiently short that when the boiler is in use, the support studs are cooled by conduction of heat to the process tubes and the roof casing thereby maintaining the temperature of the stud so that it does not exceed 1400.degree. F.

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)

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)

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.

Capping it Off.

ERIC Educational Resources Information Center

Pflugh, John E.

1996-01-01

Describes how a metal roofing system can offer a variety of cost and design benefits when retrofitting a facility. Discusses the available options in metal roofing systems, steps to take when initiating a retrofit, and suggested precautions, such as moisture control, when installing the new roof. (RJM)

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)

Building with integral solar-heat storage--Starkville, Mississippi

NASA Technical Reports Server (NTRS)

1981-01-01

Column supporting roof also houses rock-storage bin of solar-energy system supplying more than half building space heating load. Conventional heaters supply hot water. Since bin is deeper and narrower than normal, individual pebble size was increased to keep airflow resistance at minimum.

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.

30 CFR 75.211 - Roof testing and scaling.

Code of Federal Regulations, 2011 CFR

2011-07-01

... examination does not disclose a hazardous condition, sound and vibration roof tests, or other equivalent tests, shall be made where supports are to be installed. When sound and vibration tests are made, they shall be...

30 CFR 75.211 - Roof testing and scaling.

Code of Federal Regulations, 2014 CFR

2014-07-01

... examination does not disclose a hazardous condition, sound and vibration roof tests, or other equivalent tests, shall be made where supports are to be installed. When sound and vibration tests are made, they shall be...

30 CFR 75.211 - Roof testing and scaling.

Code of Federal Regulations, 2012 CFR

2012-07-01

... examination does not disclose a hazardous condition, sound and vibration roof tests, or other equivalent tests, shall be made where supports are to be installed. When sound and vibration tests are made, they shall be...

30 CFR 75.211 - Roof testing and scaling.

Code of Federal Regulations, 2013 CFR

2013-07-01

... examination does not disclose a hazardous condition, sound and vibration roof tests, or other equivalent tests, shall be made where supports are to be installed. When sound and vibration tests are made, they shall be...

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.

Evaluation of Green Roof Plants and Materials for Semi-Arid Climates

EPA Science Inventory

Abstract While green roof systems have proven to be highly effective in the evaporative cooling of buildings, reduction of roof top temperatures, protection of roof membranes from solar radiation degradation, reducing stormwater runoff, as well as beautification of the urban roo...

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...

Roofing: Don't Let What's Over Head Kill Your Bottom Line.

ERIC Educational Resources Information Center

Shannon, James W., Jr.

1983-01-01

A Colorado school district employs a professional consulting firm to give an unbiased opinion on the district's roofing needs. Built-up, single-ply, and modified asphalt roofing systems have all been utilized. Preventive maintenance keeps roofing bills to a minimum. (MLF)

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.

Solar collector cell and roof flashing assembly and method of constructing a roof with such an assembly

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayerovitch, M.D.

1980-03-25

A solar collector cell formed as an integral portion of a roof flashing is disclosed as comprising a flashing base having a dihedral surface including a larger base portion and a smaller ramp portion, and a solar collector cell container built integrally with the base portion of the flashing. The combination is designed to be installed in the roof of a dwelling or other building structure. The container portion of the flashing is substantially shorter in height above the roof line than conventional solar collector cell structures added to a roof subsequent to its construction. As a result, the inventionmore » gives the building constructor or owner, the option of either including the solar cell components at the time of construction of the roof to provide a solar heating device, or to fill the solar collector cell container with a temporary support structure, such as roof shakes or tiles. The shape of the solar collector cell and flashing assembly permits the solar collector cell structure to be camouflaged by overlying shakes or tiles of which the roof is constructed.« less

Integrated Modelling and Performance Analysis of Green Roof Technologies in Urban Environments

NASA Astrophysics Data System (ADS)

Liu, Xi; Mijic, Ana; Maksimovic, Cedo

2014-05-01

As a result of the changing global climate and increase in urbanisation, the behaviour of the urban environment has been significantly altered, causing an increase in both the frequency of extreme weather events, such as flooding and drought, and also the associated costs. Moreover, uncontrolled or inadequately planned urbanisation can exacerbate the damage. The Blue-Green Dream (BGD) project therefore develops a series of components for urban areas that link urban vegetated areas (green infrastructure) with existing urban water (blue) systems, which will enhance the synergy of urban blue and green systems and provide effective, multifunctional BGD solutions to support urban adaptation to future climatic changes. Coupled with new urban water management technologies and engineering, multifunctional benefits can be gained. Some of the technologies associated with BGD solutions include green roofs, swales that might deal with runoff more effectively and urban river restoration that can produce benefits similar to those produced from sustainable urban drainage systems (SUDS). For effective implementation of these technologies, however, appropriate tools and methodologies for designing and modelling BGD solutions are required to be embedded within urban drainage models. Although several software packages are available for modelling urban drainage, the way in which green roofs and other BGD solutions are integrated into these models is not yet fully developed and documented. This study develops a physically based mass and energy balance model to monitor, test and quantitatively evaluate green roof technology for integrated BGD solutions. The assessment of environmental benefits will be limited to three aspects: (1) reduction of the total runoff volume, (2) delay in the initiation of runoff, and (3) reduction of building energy consumption, rather than water quality, visual, social or economic impacts. This physically based model represents water and heat dynamics in a layered soil profile covered with vegetation which can be used to simulate the physical behaviour of different green roof systems in response to rainfall under various climatic conditions. Because it is a physically based model, this model could be generalised to other atmosphere-plant-soil systems. The validity of this mass and energy balance approach will be demonstrated by comparing its outcomes with observations from a green roof experimental site in London, UK.

The design of a mechanical referencing system for the rear drum of the Longwall Shearer Coal Miner

NASA Technical Reports Server (NTRS)

Jones, E. W.; Yang, T. C. H.

1981-01-01

The design of two systems which reference the position of a longwall shearer coal miner to the mine roof of the present cut and of the last cut are presented. This system is part of an automation system that will guide the rear cutting drum in such a manner that the total depth of cut remains constant even though the front drum may be following an undulating roof profile. The rear drum referencing mechanism continually monitors the distance from the mine roof to the floor for the present cut. This system provides a signal to control a constant depth of cut. The last cut follower mechanism continually monitors the distance from the mine roof of the prior cut to the cutting drum. This latter system provides a signal to minimize the step height in the roof between cuts. The dynamic response of this hydraulic-pneumatic and mechanical system is analyzed to determine accumulator size and precharge pressure.

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.

Footwear effects on walking balance at elevation.

PubMed

Simeonov, Peter; Hsiao, Hongwei; Powers, John; Ammons, Douglas; Amendola, Alfred; Kau, Tsui-Ying; Cantis, Douglas

2008-12-01

The study evaluated the effects of shoe style on workers' instability during walking at elevation. Twenty-four construction workers performed walking tasks on roof planks in a surround-screen virtual reality system, which simulated a residential roof environment. Three common athletic and three work shoe styles were tested on wide, narrow and tilted planks on a simulated roof and on an unrestricted surface at simulated ground. Dependent variables included lateral angular velocities of the trunk and the rear foot, as well as the workers' rated perceptions of instability. The results demonstrated that shoe style significantly affected workers walking instability at elevated work environments. The results highlighted two major shoe-design pathways for improving walking balance at elevation: enhancing rear foot motion control; and improving ankle proprioception. This study also outlined some of the challenges in optimal shoe selection and specific shoe-design needs for improved walking stability during roof work. The study adds to the knowledge in the area of balance control, by emphasising the role of footwear as a critical human-support surface interface during work on narrow surfaces at height. The results can be used for footwear selection and improvements to reduce risk of falls from elevation.

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.

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.

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2014 CFR

2014-07-01

... systems. (1) Systematic supplemental support should be installed throughout— (i) The tailgate entry of the first longwall panel prior to any mining; and (ii) In the proposed tailgate entry of each subsequent... should address— (i) Notification of miners that the travelway is blocked; (ii) Re-instruction of miners...

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2012 CFR

2012-07-01

... systems. (1) Systematic supplemental support should be installed throughout— (i) The tailgate entry of the first longwall panel prior to any mining; and (ii) In the proposed tailgate entry of each subsequent... should address— (i) Notification of miners that the travelway is blocked; (ii) Re-instruction of miners...

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2013 CFR

2013-07-01

... systems. (1) Systematic supplemental support should be installed throughout— (i) The tailgate entry of the first longwall panel prior to any mining; and (ii) In the proposed tailgate entry of each subsequent... should address— (i) Notification of miners that the travelway is blocked; (ii) Re-instruction of miners...

78 FR 42507 - Proposed Establishment of a Federally Funded Research and Development Center-Third Notice

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-16

... and private sectors. The activity includes staff support for information technology operations... technologies. The NCCoE will bring together experts from industry, government and academia under one roof to... Information Technology (IT) systems. By accelerating dissemination and use of these integrated tools and...

Hybrid Automatic Building Interpretation System

NASA Astrophysics Data System (ADS)

Pakzad, K.; Klink, A.; Müterthies, A.; Gröger, G.; Stroh, V.; Plümer, L.

2011-09-01

HABIS (Hybrid Automatic Building Interpretation System) is a system for an automatic reconstruction of building roofs used in virtual 3D building models. Unlike most of the commercially available systems, HABIS is able to work to a high degree automatically. The hybrid method uses different sources intending to exploit the advantages of the particular sources. 3D point clouds usually provide good height and surface data, whereas spatial high resolution aerial images provide important information for edges and detail information for roof objects like dormers or chimneys. The cadastral data provide important basis information about the building ground plans. The approach used in HABIS works with a multi-stage-process, which starts with a coarse roof classification based on 3D point clouds. After that it continues with an image based verification of these predicted roofs. In a further step a final classification and adjustment of the roofs is done. In addition some roof objects like dormers and chimneys are also extracted based on aerial images and added to the models. In this paper the used methods are described and some results are presented.

A Context-Driven Model for the Flat Roofs Construction Process through Sensing Systems, Internet-of-Things and Last Planner System

PubMed Central

Andújar-Montoya, María Dolores

2017-01-01

The main causes of building defects are errors in the design and the construction phases. These causes related to construction are mainly due to the general lack of control of construction work and represent approximately 75% of the anomalies. In particular, one of the main causes of such anomalies, which end in building defects, is the lack of control over the physical variables of the work environment during the execution of tasks. Therefore, the high percentage of defects detected in buildings that have the root cause in the construction phase could be avoidable with a more accurate and efficient control of the process. The present work proposes a novel integration model based on information and communications technologies for the automation of both construction work and its management at the execution phase, specifically focused on the flat roof construction process. Roofs represent the second area where more defects are claimed. The proposed model is based on a Web system, supported by a service oriented architecture, for the integral management of tasks through the Last Planner System methodology, but incorporating the management of task restrictions from the physical environment variables by designing specific sensing systems. Likewise, all workers are integrated into the management process by Internet-of-Things solutions that guide them throughout the execution process in a non-intrusive and transparent way. PMID:28737693

A Context-Driven Model for the Flat Roofs Construction Process through Sensing Systems, Internet-of-Things and Last Planner System.

PubMed

Andújar-Montoya, María Dolores; Marcos-Jorquera, Diego; García-Botella, Francisco Manuel; Gilart-Iglesias, Virgilio

2017-07-22

The main causes of building defects are errors in the design and the construction phases. These causes related to construction are mainly due to the general lack of control of construction work and represent approximately 75% of the anomalies. In particular, one of the main causes of such anomalies, which end in building defects, is the lack of control over the physical variables of the work environment during the execution of tasks. Therefore, the high percentage of defects detected in buildings that have the root cause in the construction phase could be avoidable with a more accurate and efficient control of the process. The present work proposes a novel integration model based on information and communications technologies for the automation of both construction work and its management at the execution phase, specifically focused on the flat roof construction process. Roofs represent the second area where more defects are claimed. The proposed model is based on a Web system, supported by a service oriented architecture, for the integral management of tasks through the Last Planner System methodology, but incorporating the management of task restrictions from the physical environment variables by designing specific sensing systems. Likewise, all workers are integrated into the management process by Internet-of-Things solutions that guide them throughout the execution process in a non-intrusive and transparent way.

Urban reconciliation ecology: the potential of living roofs and walls.

PubMed

Francis, Robert A; Lorimer, Jamie

2011-06-01

Reconciling human and non-human use of urban regions to support biological conservation represents a major challenge for the 21st century. The concept of reconciliation ecology, by which the anthropogenic environment may be modified to encourage non-human use and biodiversity preservation without compromising societal utilization, potentially represents an appropriate paradigm for urban conservation given the generally poor opportunities that exist for reserve establishment and ecological restoration in urban areas. Two habitat improvement techniques with great potential for reconciliation ecology in urban areas are the installation of living roofs and walls, which have been shown to support a range of taxa at local scales. This paper evaluates the reconciliation potential of living roofs and walls, in particular highlighting both ecological and societal limitations that need to be overcome for application at the landscape scale. We further consider that successful utilization of living roofs and walls for urban reconciliation ecology will rely heavily on the participation of urban citizens, and that a 'citizen science' model is needed to facilitate public participation and support and to create an evidence base to determine their effectiveness. Living roofs and walls are just one aspect of urban reconciliation ecology, but are particularly important 'bottom-up' techniques for improving urban biodiversity that can be performed directly by the citizenry. Copyright © 2011 Elsevier Ltd. All rights reserved.

DART Support for Hurricane Matthew

NASA Image and Video Library

2016-10-13

Members of the Disaster Assessment and Recovery Team (DART) repair a section of roof atop the Operations Support Building II at NASA’s Kennedy Space Center in Florida. The effort is part of the spaceport’s ongoing recovery from Hurricane Matthew, which passed to the east of Kennedy on Oct. 6 and 7, 2016. The center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected.

Hough transform as a tool support building roof detection. (Polish Title: Transformata Hough'a jako narzędzie wspomagające wykrywanie dachów budynków)

NASA Astrophysics Data System (ADS)

Borowiec, N.

2013-12-01

Gathering information about the roof shapes of the buildings is still current issue. One of the many sources from which we can obtain information about the buildings is the airborne laser scanning. However, detect information from cloud o points about roofs of building automatically is still a complex task. You can perform this task by helping the additional information from other sources, or based only on Lidar data. This article describes how to detect the building roof only from a point cloud. To define the shape of the roof is carried out in three tasks. The first step is to find the location of the building, the second is the precise definition of the edge, while the third is an indication of the roof planes. First step based on the grid analyses. And the next two task based on Hough Transformation. Hough transformation is a method of detecting collinear points, so a perfect match to determine the line describing a roof. To properly determine the shape of the roof is not enough only the edges, but it is necessary to indicate roofs. Thus, in studies Hough Transform, also served as a tool for detection of roof planes. The only difference is that the tool used in this case is a three-dimensional.

Roofing research: a bibliography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robinson, J.N.; Nichols, C.L.

1981-04-01

A listing, indexed by subject, primary author, and secondary authors, is presented of some 530 references in the literature related to roofing research - materials, construction, and in-service problems. Structural design of roofing systems is not covered.

32 CFR 644.450 - Items excluded from usual restoration obligation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... gypsum block walls. (3) Floor joints, roof trusses (including roof boards and roofing), and framing..., ventilators, and metal ceilings. (8) Structural steel or iron. (9) Fire escapes. (10) Heating systems. (11...

32 CFR 644.450 - Items excluded from usual restoration obligation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... gypsum block walls. (3) Floor joints, roof trusses (including roof boards and roofing), and framing..., ventilators, and metal ceilings. (8) Structural steel or iron. (9) Fire escapes. (10) Heating systems. (11...

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.

Development of a Green Roof Environmental Monitoring and Meteorological Network in New York City

PubMed Central

Gaffin, Stuart R.; Khanbilvardi, Reza; Rosenzweig, Cynthia

2009-01-01

Green roofs (with plant cover) are gaining attention in the United States as a versatile new environmental mitigation technology. Interest in data on the environmental performance of these systems is growing, particularly with respect to urban heat island mitigation and stormwater runoff control. We are deploying research stations on a diverse array of green roofs within the New York City area, affording a new opportunity to monitor urban environmental conditions at small scales. We show some green roof systems being monitored, describe the sensor selection employed to study energy balance, and show samples of selected data. These roofs should be superior to other urban rooftops as sites for meteorological stations. PMID:22574037

Development of a green roof environmental monitoring and meteorological network in new york city.

PubMed

Gaffin, Stuart R; Khanbilvardi, Reza; Rosenzweig, Cynthia

2009-01-01

Green roofs (with plant cover) are gaining attention in the United States as a versatile new environmental mitigation technology. Interest in data on the environmental performance of these systems is growing, particularly with respect to urban heat island mitigation and stormwater runoff control. We are deploying research stations on a diverse array of green roofs within the New York City area, affording a new opportunity to monitor urban environmental conditions at small scales. We show some green roof systems being monitored, describe the sensor selection employed to study energy balance, and show samples of selected data. These roofs should be superior to other urban rooftops as sites for meteorological stations.

Effect of age and rainfall pH on contaminant yields from metal roofs.

PubMed

Wicke, Daniel; Cochrane, Thomas A; O'Sullivan, Aisling D; Cave, Simon; Derksen, Mark

2014-01-01

Metal roofs are recognized for conveying significant metal loads to urban streams through stormwater runoff. Metal concentrations in urban runoff depend on roof types and prevailing weather conditions but the combined effects of roof age and rainfall pH on metal mobilization are not well understood. To investigate these effects on roof runoff, water quality was analysed from galvanized iron and copper roofs following rainfall events and also from simulating runoff using a rainfall simulator on specially constructed roof modules. Zinc and copper yields under different pH regimes were investigated for two roof materials and two different ages. Metal mobilization from older roofs was greater than new roofs with 55-year-old galvanized roof surfaces yielding more Zn, on average increasing by 45% and 30% under a rainfall pH of 4 and 8, respectively. Predominantly dissolved (85-95%) Zn and Cu concentrations in runoff exponentially increased as the rainfall pH decreased. Results also confirmed that copper guttering and downpipes associated with galvanized steel roof systems can substantially increase copper levels in roof runoff. Understanding the dynamics of roof surfaces as a function of weathering and rainfall pH regimes can help developers with making better choices about roof types and materials for stormwater improvement.

Operation UPSHOT-KNOTHOLE, Nevada Proving Grounds, March-June 1953. Project 3.5 Tests on the Response of Wall and Roof Panels and the Transmission of Load to Supporting Structure

DTIC Science & Technology

1955-05-01

56 4.23 Postshot, 3.5ba, Interior of Test Cell . . . . . . . . • • 57 4.24 Postshot, 35.Sbb, Damage to Precast Concrete Channel Roof 6...Predicted Applied and Measured Transmitted Forces, Roof Panel 3.5bb (3-1/2 in. precast concrete channels on steel purlins) . . . o . o . ... . ... 104 5.16...truss rafters 3.Sba Bowstring truss with wood 4500 4200 10 7.1 10 decking, tar and gravel roofing 3.5bb 3-1/2 in. precast concrete channels on steel

Longwall gate road stability in a steeply pitching thick coal seam with a weak roof. Report of investigations/1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barron, L.R.; DeMarco, M.J.

1995-12-31

The U.S. Bureau of Mines conducted a ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. This report discusses gate road layout and performance and secondary support effectiveness. The results of the pillar pressure study are compared to pillar loading predicted by a widely used pillar design method and to similar studies in other mines. A stability evaluation of the most recent longwall headgate, using the USBM Analysis of Longwall Pillar Stability (ALPS) indicates marginal stability in first-panel mining and instability in second-panelmore » mining. ALPS and the USBM Coal Mine Roof Rating (CMRR) system are used to evaluate tailgate-mining stability of the previous gate roads and to determine pillar and entry width and top coal thickness criteria for tailgate stability in future panels.« less

Potential benefits of plant diversity on vegetated roofs: a literature review.

PubMed

Cook-Patton, Susan C; Bauerle, Taryn L

2012-09-15

Although vegetated green roofs can be difficult to establish and maintain, they are an increasingly popular method for mitigating the negative environmental impacts of urbanization. Most green roof development has focused on maximizing green roof performance by planting one or a few drought-tolerant species. We present an alternative approach, which recognizes green roofs as dynamic ecosystems and employs a diversity of species. We draw links between the ecological and green roof literature to generate testable predictions about how increasing plant diversity could improve short- and long-term green roof functioning. Although we found few papers that experimentally manipulated diversity on green roofs, those that did revealed ecological dynamics similar to those in more natural systems. However, there are many unresolved issues. To improve overall green roof performance, we should (1) elucidate the links among plant diversity, structural complexity, and green roof performance, (2) describe feedback mechanisms between plant and animal diversity on green roofs, (3) identify species with complementary traits, and (4) determine whether diverse green roof communities are more resilient to disturbance and environmental change than less diverse green roofs. Copyright © 2012 Elsevier Ltd. All rights reserved.

Revisiting the Climate Impacts of Cool Roofs around the Globe Using an Earth System Model

NASA Astrophysics Data System (ADS)

Zhang, J.; Ban-Weiss, G. A.; Zhang, K.; Liu, J.

2016-12-01

Solar reflective "cool roofs" absorb less sunlight than traditional dark roofs, reducing solar heat gain, and decreasing the amount of heat transferred to the atmosphere. Widespread adoption of cool roofs could therefore reduce temperatures in urban areas, partially mitigating the urban heat island effect, and contributing to reversing the local impacts of global climate change. The impacts of cool roofs on global climate remain debated by past research and are uncertain. Using a sophisticated Earth system model, the impacts of cool roofs on climate are investigated at urban, continental, and global scales. We find that global adoption of cool roofs in urban areas reduces urban heat islands everywhere, with an annual- and global-mean decrease from 1.6 to 1.2 K. Decreases are statistically significant, except for some areas in Africa and Mexico where urban fraction is low, and some high-latitude areas during wintertime. Analysis of the surface and TOA energy budget in urban regions at continental-scale shows cool roofs causing increases in solar radiation leaving the Earth-atmosphere system in most regions around the globe, though the presence of aerosols and clouds are found to partially offset increases in upward radiation. Aerosols dampen cool roof-induced increases in upward solar radiation, ranging from 4% in the United States to 18% in more polluted China. Adoption of cool roofs also causes statistically significant reductions in surface air temperatures in urbanized regions of China (-0.11±0.10 K) and the United States (-0.14±0.12 K); India and Europe show statistically insignificant changes. Though past research has disagreed on whether widespread adoption of cool roofs would cool or warm global climate, these studies have lacked analysis on the statistical significance of global temperature changes. The research presented here indicates that adoption of cool roofs around the globe would lead to statistically insignificant reductions in global mean air temperature (-0.0021 ± 0.026 K). Thus, we suggest that while cool roofs are an effective tool for reducing building energy use in hot climates, urban heat islands, and regional air temperatures, their influence on global climate is likely negligible.

Hygrothermal Performance of West Coast Wood Deck Roofing System

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 watermore » 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.« less

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.

Steep-Slope Assembly Testing of Clay and Concrete Tile With and Without Cool Pigmented Colors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, William A

Cool color pigments and sub-tile venting of clay and concrete tile roofs significantly impact the heat flow crossing the roof deck of a steep-slope roof. Field measures for the tile roofs revealed a 70% drop in the peak heat flow crossing the deck as compared to a direct-nailed asphalt shingle roof. The Tile Roofing Institute (TRI) and its affiliate members are keenly interested in documenting the magnitude of the drop for obtaining solar reflectance credits with state and federal "cool roof" building efficiency standards. Tile roofs are direct-nailed or are attached to a deck with batten or batten and counter-battenmore » construction. S-Misson clay and concrete tile roofs, a medium-profile concrete tile roof, and a flat slate tile roof were installed on fully nstrumented attic test assemblies. Temperature measures of the roof, deck, attic, and ceiling, heat flows, solar reflectance, thermal emittance, and the ambient weather were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventional pigmented and directnailed asphalt shingle roof. ORNL measured the tile's underside temperature and the bulk air temperature and heat flows just underneath the tile for batten and counter-batten tile systems and compared the results to the conventional asphalt shingle.« less

Saint Joseph's University Institute for Environmental Stewardship

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCann, Micahel P.; Springer, Clint J.

Task A: Examination of the physiological, morphological, and reproductive responses of Panicum virgatum (switchgrass) cultivars identified as potential biofuel producing cultivars as well as naturally-occurring varieties of switchgrass to projected changes in climate for the central portion of the United States. This project was a multi-year project set in a field site located at the Konza Prairie Biological Station near Manhattan, KS USA. The major objective of the study was to understand the physiological and growth responses of the important biofuel grass species, Panicum virgatum (switch grass) to simulated changes in precipitation expected for the Central Plains region of themore » United States. Population level adaptation to broad-scale regional climates or within-population variation in genome size of this genetically and phenotypically diverse C4 grass species may influence the responses to future precipitation variability associated with climate change. Therefore, we investigated switchgrass responses to water variability between natural populations collected across latitudinal gradient and populations. P. virgatum plants from natural populations originating from Kansas, Oklahoma, and Texas received frequent, small precipitation events (“ambient’) or infrequent, large precipitation events (‘altered”) to simulate contrasting rainfall variability expected from this region. We measured leaf-level physiology, aboveground biomass varied significantly by population origin but did not differ by genome size. Our results suggest that trait variation in P. virgatum is primarily attributed to population-level adaptation across latitudinal gradient, not genome size, and that neither population-level adaptation nor genome size may be important predictors of P. virgatum responses to future climatic conditions. Based solely on the data presented here, the most important consideration when deciding what varieties of switchgrass to cultivate for biofuel feedstocks under future climate scenarios is local adaptation and not necessarily genome size as has been hypothesized in the literature. Task B: Installation of an extensive green roof system on the Science Center at Saint Joseph's University for research, research-training and educational outreach activities. An experimental green roof system was designed and installed by an outside contractor (Roofmeadows) on the roof of the Science Center at Saint Joseph's University. The roof system includes four test plots, each with a different drainage system, instrumentation to monitor storm water retention, roof deck temperature, heat flux into and out of the building, rain fall, wind speed and direction, relative humidity and heat emission from the roof system. The vegetative roof was planted with 26 species of plants, distributed throughout the roof area, to assess species/variety growth and coverage characteristics, both in terms of the different drain layer systems, and in terms of the different exposures along the north to south axis of the building. Analysis of the drain layer performance, in terms of storm water retention, shows that the aggregate (stone) drainage layer system performed the best, with the moisture management mat system second, and the geotextile drain layer and reservoir sheet layer systems coming in last. This information is of value in the planning and design of vegetative roof systems since the different types of drainage layer systems have different installation costs and different weights. The different drainage layer systems also seem to be having an impact on plant growth and spread with the test plot with the reservoir sheet layer actually having the poorest plant coverage and plant spread of all areas of the roof studied. Plant growth performance analysis is ongoing, but significant differences have been observed in the third growing season ('13) along the north to south axis, with most species doing better towards the northern end of the roof (in terms of percent ground coverage and plant spread and reproduction). Interestingly, plant growth in all four of the test plots was reduced relative to the lower areas of the roof (the lower area was ca. 2 inches lower than the test plots, due to the space needed for sensors under the plots. The lower roof area uses an aggregate drain layer comparable to that in the third test plot), even when accounting for the north to south differences. The reasons for these differences are not clear and studies are underway to examine the impact of wind scour, drainage rates, temperature, and other factors. This information will be of value to planners of extensive vegetative roof systems in the Philadelphia (and broader) region, since plant growth and roof system overall performance is influenced by local climate, making broad generalizations of performance difficult. Task C: Education and community outreach efforts by the IES involving conferences at SJU, presentations by faculty and students off campus, and educational signage. The Institute for Environmental Stewardship hosted three storm water management workshops on the SJU campus in Philadelphia, in collaboration with the Lower Merion Conservancy, a not-for-profit organization located in Montgomery County, PA. These workshops were free and open to the public. The three workshops (held each year in March) drew more than 200 participants total. The presenters included local and state government agencies, not for profit organizations involved in storm water and open space preservation, designers, engineers, planners and others. Feedback was uniformly positive and we plan to continue the workshops for the foreseeable future. Educational signage has been installed at four locations on campus to explain campus infrastructure related to storm water (rain gardens, vegetative roof and green facades), as well as detailed signage installed on the Science Center roof for the vegetative roof system. More than 100 people (from in and outside of SJU) have thus far participated in tours of the roof system. A digital signage system has been installed in the adjacent library and this system provides information about the vegetative roof project and other efforts. A web camera system for the roof has also been installed and the video will be simulcast to the digital signage and with web site (www.sju.edu/ies) in the near future.« less

Analysis of three-year Wisconsin temperature histories for roof systems using wood, wood-thermoplastic composite, and fiberglass shingles

Treesearch

Jerrold E. Winandy; Cherilyn A. Hatfield

2007-01-01

Temperature histories for various types of roof shingles, wood roof sheathing, rafters, and nonventilated attics were monitored in outdoor attic structures using simulated North American light-framed construction. In this paper, 3-year thermal load histories for wood-based composite roof sheathing, wood rafters, and attics under western redcedar (WRC) shingles, wood-...

Investigation on the Influence of Abutment Pressure on the Stability of Rock Bolt Reinforced Roof Strata Through Physical and Numerical Modeling

NASA Astrophysics Data System (ADS)

Kang, Hongpu; Li, Jianzhong; Yang, Jinghe; Gao, Fuqiang

2017-02-01

In underground coal mining, high abutment loads caused by the extraction of coal can be a major contributor to many rock mechanic issues. In this paper, a large-scale physical modeling of a 2.6 × 2.0 × 1.0 m entry roof has been conducted to investigate the fundamentals of the fracture mechanics of entry roof strata subjected to high abutment loads. Two different types of roof, massive roof and laminated roof, are considered. Rock bolt system has been taken into consideration. A distinct element analyses based on the physical modeling conditions have been performed, and the results are compared with the physical results. The physical and numerical models suggest that under the condition of high abutment loads, the massive roof and the laminated roof fail in a similar pattern which is characterized as vertical tensile fracturing in the middle of the roof and inclined shear fracturing initiated at the roof and rib intersections and propagated deeper into the roof. Both the massive roof and the laminated roof collapse in a shear sliding mode shortly after shear fractures are observed from the roof surface. It is found that shear sliding is a combination of tensile cracking of intact rock and sliding on bedding planes and cross joints. Shear sliding occurs when the abutment load is much less than the compressive strength of roof.

An analysis of roof bolter fatalities and injuries in U.S. mining

PubMed Central

Sammarco, J.J.; Podlesny, A.; Rubinstein, E.N.; Demich, B.

2017-01-01

Roof bolting typically follows the extraction of a commodity to help keep the roof from collapsing. During 2004 to 2013, roof bolter operators had the highest number of machinery-related injuries, accounting for 64.7 percent, at underground coal mines. This paper analyzes U.S. roof bolter fatal and nonfatal lost-time injury data at underground work locations for all commodities from 2004 through 2013 and determines risk indices for six roof bolting tasks. For fatal and nonfatal incidences combined, the roof bolting tasks in order of the highest to lowest risk index were bolting, handling of materials, setting the temporary roof support (TRS), drilling, tramming, and traversing. For fatalities, the roof bolting tasks in order of the highest to lowest risk index were handling of materials, setting the TRS, bolting, drilling, traversing, and tramming. Age was found to be a significant factor. Severity of injury, indicated by days lost, was found to increase with increasing age as well as with increasing experience, largely due to the confounding of age and experience. The operation of the roof bolting machine used in underground mining should be a research priority given the high frequency and severity of incidents. The results also suggest that temporal factors may exist, so additional research is warranted to better understand these factors and potentially develop interventions. This research provides a data-driven foundation from which future research can be conducted for safety interventions to reduce the frequency and severity of incidences involving the roof bolter activities of bolting, handling of materials, and setting the TRS. PMID:28845099

Modelling Mean Albedo of Individual Roofs in Complex Urban Areas Using Satellite Images and Airborne Laser Scanning Point Clouds

NASA Astrophysics Data System (ADS)

Kalantar, B.; Mansor, S.; Khuzaimah, Z.; Sameen, M. Ibrahim; Pradhan, B.

2017-09-01

Knowledge of surface albedo at individual roof scale is important for mitigating urban heat islands and understanding urban climate change. This study presents a method for quantifying surface albedo of individual roofs in a complex urban area using the integration of Landsat 8 and airborne LiDAR data. First, individual roofs were extracted from airborne LiDAR data and orthophotos using optimized segmentation and supervised object based image analysis (OBIA). Support vector machine (SVM) was used as a classifier in OBIA process for extracting individual roofs. The user-defined parameters required in SVM classifier were selected using v-fold cross validation method. After that, surface albedo was calculated for each individual roof from Landsat images. Finally, thematic maps of mean surface albedo of individual roofs were generated in GIS and the results were discussed. Results showed that the study area is covered by 35% of buildings varying in roofing material types and conditions. The calculated surface albedo of buildings ranged from 0.16 to 0.65 in the study area. More importantly, the results indicated that the types and conditions of roofing materials significantly effect on the mean value of surface albedo. Mean albedo of new concrete, old concrete, new steel, and old steel were found to be equal to 0.38, 0.26, 0.51, and 0.44 respectively. Replacing old roofing materials with new ones should highly prioritized.

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.

Effects of roof and rainwater characteristics on copper concentrations in roof runoff.

PubMed

Bielmyer, Gretchen K; Arnold, W Ray; Tomasso, Joseph R; Isely, Jeff J; Klaine, Stephen J

2012-05-01

Copper sheeting is a common roofing material used in many parts of the world. However, copper dissolved from roof sheeting represents a source of copper ions to watersheds. Researchers have studied and recently developed a simple and efficient model to predict copper runoff rates. Important input parameters include precipitation amount, rain pH, and roof angle. We hypothesized that the length of a roof also positively correlates with copper concentration (thus, runoff rates) on the basis that runoff concentrations should positively correlate with contact time between acidic rain and the copper sheet. In this study, a novel system was designed to test and model the effects of roof length (length of roof from crown to the drip edge) on runoff copper concentrations relative to rain pH and roof angle. The system consisted of a flat-bottom copper trough mounted on an apparatus that allowed run length and slope to be varied. Water of known chemistry was trickled down the trough at a constant rate and sampled at the bottom. Consistent with other studies, as pH of the synthetic rainwater decreased, runoff copper concentrations increased. At all pH values tested, these results indicated that run length was more important in explaining variability in copper concentrations than was the roof slope. The regression equation with log-transformed data (R(2) = 0.873) accounted for slightly more variability than the equation with untransformed data (R(2) = 0.834). In log-transformed data, roof angle was not significant in predicting copper concentrations.

Magma-driven antiform structures in the Afar rift: The Ali Sabieh range, Djibouti

NASA Astrophysics Data System (ADS)

Le Gall, Bernard; Daoud, Mohamed Ahmed; Maury, René C.; Rolet, Joël; Guillou, Hervé; Sue, Christian

2010-06-01

The Ali Sabieh Range, SE Afar, is an antiform involving Mesozoic sedimentary rocks and synrift volcanics. Previous studies have postulated a tectonic origin for this structure, in either a contractional or extensional regime. New stratigraphic, mapping and structural data demonstrate that large-scale doming took place at an early stage of rifting, in response to a mafic laccolithic intrusion dated between 28 and 20 Ma from new K-Ar age determinations. Our 'laccolith' model is chiefly supported by: (i) the geometry of the intrusion roof, (ii) the recognition of roof pendants in its axial part, and (iii) the mapping relationships between the intrusion, the associated dyke-sill network, and the upper volcanic/volcaniclastic sequences. The laccolith is assumed to have inflated with time, and to have upwardly bent its sedimentary roof rocks. From the architecture of the ˜1 km-thick Mesozoic overburden sequences, ca. 2 km of roof lifting are assumed to have occurred, probably in association with reactivated transverse discontinuities. Computed paleostress tensors indicate that the minimum principal stress axis is consistently horizontal and oriented E-W, with a dominance of extensional versus strike-slip regimes. The Ali Sabieh laccolith is the first regional-scale magma-driven antiform structure reported so far in the Afro-Arabian rift system.

Third symposium on underground mining

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1977-01-01

The Third Symposium on Underground Mining was held at the Kentucky Fair and Exposition Center, Louisville, KY, October 18--20, 1977. Thirty-one papers have been entered individually into EDB and ERA. The topics covered include mining system (longwall, shortwall, room and pillar, etc.), mining equipment (continuous miners, longwall equipment, supports, roof bolters, shaft excavation equipment, monitoring and control systems. Maintenance and rebuilding facilities, lighting systems, etc.), ventilation, noise abatement, economics, accidents (cost), dust control and on-line computer systems. (LTN)

DART Support for Hurricane Matthew

NASA Image and Video Library

2016-10-26

Following Hurricane Matthew, repairs have been made to the roof of the Operations Support Building (OSB) II in the Launch Complex 39 area at NASA's Kennedy Space Center in Florida. Assessments and repairs continue on various structures and facilities across the spaceport, part of the ongoing recovery from the storm, which passed to the east of Kennedy on Oct. 6 and 7, 2016. The center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected.

Structurally integrated steel solar collector

DOEpatents

Moore, Stanley W.

1977-03-08

Herein is disclosed a flat plate solar heat collector unit. The solar collector is integrated as a structural unit so that the collector also functions as the building roof. The functions of efficient heat collection, liquid coolant flow passages, roof structural support and building insulation are combined into one unit.

Structurally integrated steel solar collector

DOEpatents

Moore, S.W.

1975-06-03

Herein is disclosed a flate plate solar heat collector unit. The solar collector is integrated as a structural unit so that the collector also functions as the building roof. The functions of efficient heat collection, liquid coolant flow passages, roof structural support, and building insulation are combined into one unit.

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.

Analysis of the design and performance characteristics of pumpable roof supports

PubMed Central

Timothy, Batchler

2017-01-01

Pumpable roof supports are currently being used to provide a safe working environment for longwall mining. Because different pumpable supports are visually similar and installed fundamentally in the same manner as other supports, there is a tendency to believe they all perform the same way. However, there are several design parameters that can affect their performance, including the cementitious material properties and the bag construction practices that influence the degree of confinement provided. A full understanding of the impact of these design parameters is necessary to optimize the support application and to provide a foundation for making further improvements in the support performance. This paper evaluates the impact of various support design parameters by examining full-scale performance tests conducted using the National Institute for Occupational Safety and Health (NIOSH) Mine Roof Simulator (MRS) as part of manufacturers’ developmental and quality control testing. These tests were analyzed to identify correlations between the support design parameters and the resulting performance. Based on more than 160 tests over 7 years, quantifiable patterns were examined to assess the correlation between the support dimensions, cementitious material type, wire pitch, and single-wall vs. dual-walled bag designs to the support capacity, stiffness, load shedding events, and yield characteristics. PMID:28775910

Revisiting the climate impacts of cool roofs around the globe using an Earth system model

NASA Astrophysics Data System (ADS)

Zhang, Jiachen; Zhang, Kai; Liu, Junfeng; Ban-Weiss, George

2016-08-01

Solar reflective ‘cool roofs’ absorb less sunlight than traditional dark roofs, reducing solar heat gain, and decreasing the amount of heat transferred to the atmosphere. Widespread adoption of cool roofs could therefore reduce temperatures in urban areas, partially mitigating the urban heat island effect, and contributing to reversing the local impacts of global climate change. The impacts of cool roofs on global climate remain debated by past research and are uncertain. Using a sophisticated Earth system model, the impacts of cool roofs on climate are investigated at urban, continental, and global scales. We find that global adoption of cool roofs in urban areas reduces urban heat islands everywhere, with an annual- and global-mean decrease from 1.6 to 1.2 K. Decreases are statistically significant, except for some areas in Africa and Mexico where urban fraction is low, and some high-latitude areas during wintertime. Analysis of the surface and TOA energy budget in urban regions at continental-scale shows cool roofs causing increases in solar radiation leaving the Earth-atmosphere system in most regions around the globe, though the presence of aerosols and clouds are found to partially offset increases in upward radiation. Aerosols dampen cool roof-induced increases in upward solar radiation, ranging from 4% in the United States to 18% in more polluted China. Adoption of cool roofs also causes statistically significant reductions in surface air temperatures in urbanized regions of China (-0.11 ± 0.10 K) and the United States (-0.14 ± 0.12 K); India and Europe show statistically insignificant changes. Though past research has disagreed on whether widespread adoption of cool roofs would cool or warm global climate, these studies have lacked analysis on the statistical significance of global temperature changes. The research presented here indicates that adoption of cool roofs around the globe would lead to statistically insignificant reductions in global mean air temperature (-0.0021 ± 0.026 K). Thus, we suggest that while cool roofs are an effective tool for reducing building energy use in hot climates, urban heat islands, and regional air temperatures, their influence on global climate is likely negligible.

Roof-top solar energy potential under performance-based building energy codes: The case of Spain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Izquierdo, Salvador; Montanes, Carlos; Dopazo, Cesar

2011-01-15

The quantification at regional level of the amount of energy (for thermal uses and for electricity) that can be generated by using solar systems in buildings is hindered by the availability of data for roof area estimation. In this note, we build on an existing geo-referenced method for determining available roof area for solar facilities in Spain to produce a quantitative picture of the likely limits of roof-top solar energy. The installation of solar hot water systems (SHWS) and photovoltaic systems (PV) is considered. After satisfying up to 70% (if possible) of the service hot water demand in every municipality,more » PV systems are installed in the remaining roof area. Results show that, applying this performance-based criterion, SHWS would contribute up to 1662 ktoe/y of primary energy (or 68.5% of the total thermal-energy demand for service hot water), while PV systems would provide 10 T W h/y of electricity (or 4.0% of the total electricity demand). (author)« less

Structural changes of green roof growing substrate layer studied by X-ray CT

NASA Astrophysics Data System (ADS)

Jelinkova, Vladimira; Sacha, Jan; Dohnal, Michal; Snehota, Michal

2017-04-01

Increasing interest in green infrastructure linked with newly implemented legislation/rules/laws worldwide opens up research potential for field of soil hydrology. A better understanding of function of engineered soils involved in green infrastructure solutions such as green roofs or rain garden is needed. A soil layer is considered as a highly significant component of the aforesaid systems. In comparison with a natural soil, the engineered soil is assumed to be the more challenging case due to rapid structure changes early stages after its build-up. The green infrastructure efficiency depends on the physical and chemical properties of the soil, which are, in the case of engineered soils, a function of its initial composition and subsequent soil formation processes. The project presented in this paper is focused on fundamental processes in the relatively thick layer of engineered soil. The initial structure development, during which the pore geometry is altered by the growth of plant roots, water influx, solid particles translocation and other soil formation processes, is investigated with the help of noninvasive imaging technique  X-ray computed tomography. The soil development has been studied on undisturbed soil samples taken periodically from green roof test system during early stages of its life cycle. Two approaches and sample sizes were employed. In the first approach, undisturbed samples (volume of about 63 cm3) were taken each time from the test site and scanned by X-ray CT. In the second approach, samples (volume of about 630 cm3) were permanently installed at the test site and has been repeatedly removed to perform X-ray CT imaging. CT-derived macroporosity profiles reveal significant temporal changes of soil structure. Clogging of pores by fine particles and fissures development are two most significant changes that would affect the green roof system efficiency. This work has been supported by the Ministry of Education, Youth and Sports within National Sustainability Programme I, project number LO1605 and with financial support from the Czech Science Foundation under project number GAČR 17-21011S.

Attic floor; view west showing roof structural system North ...

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

Attic floor; view west showing roof structural system - North Philadelphia Station, 2900 North Broad Street, on northwest corner of Broad Street & Glenwood Avenue, Philadelphia, Philadelphia County, PA

Roof sprinkling system sweats down A/C costs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This article describes a roof spray system which enhances the energy efficiency of a building's HVAC system at a nominal cost in relationship to the benefits it yields. Roof spray cooling is based on the fact that water, when it evaporates, absorbs large amounts of heat. The evaporation of one gallon of water will dissipate about 8500 BTU's of heat; and three fallons of water evaporated over one hour's time offers the same cooling capacity as a two-ton airconditioner operated over the same period. By intermittently spraying its surface with water, a direct evaporative cooling system allows a roof tomore » sweat away the sun's radiant heat, cooling an un-airconditioned building from 10 to 12 degrees mrt and reducing summer electric costs by 25%.« less

30 CFR 75.203 - Mining methods.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Mining methods. 75.203 Section 75.203 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.203 Mining methods. (a) The method of mining... faulty pillar recovery methods. Pillar dimensions shall be compatible with effective control of the roof...

30 CFR 75.203 - Mining methods.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Mining methods. 75.203 Section 75.203 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.203 Mining methods. (a) The method of mining... faulty pillar recovery methods. Pillar dimensions shall be compatible with effective control of the roof...

30 CFR 75.203 - Mining methods.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Mining methods. 75.203 Section 75.203 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.203 Mining methods. (a) The method of mining... faulty pillar recovery methods. Pillar dimensions shall be compatible with effective control of the roof...

30 CFR 75.203 - Mining methods.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Mining methods. 75.203 Section 75.203 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.203 Mining methods. (a) The method of mining... faulty pillar recovery methods. Pillar dimensions shall be compatible with effective control of the roof...

30 CFR 75.203 - Mining methods.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Mining methods. 75.203 Section 75.203 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.203 Mining methods. (a) The method of mining... faulty pillar recovery methods. Pillar dimensions shall be compatible with effective control of the roof...

75 FR 53277 - Notice of Intent To Terminate Selected National Voluntary Laboratory Accreditation Program (NVLAP...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-31

... coatings, paper and related products, building seals and sealants, plastics, plumbing, roofing, and... products, building seals and sealants, plastics, plumbing, roofing, and mattresses. The purpose of this... plumbing laboratories are also accredited for plastic and paint testing in support of plumbing testing...

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

Code of Federal Regulations, 2010 CFR

2010-07-01

... feet or more apart shall be installed with a wooden crossbar at least 3 inches thick and 8 inches wide... less than 9 feet apart shall be installed with a wooden plank at least 2 inches thick and 8 inches wide...

Can green roof act as a sink for contaminants? A methodological study to evaluate runoff quality from green roofs.

PubMed

Vijayaraghavan, K; Joshi, Umid Man

2014-11-01

The present study examines whether green roofs act as a sink or source of contaminants based on various physico-chemical parameters (pH, conductivity and total dissolved solids) and metals (Na, K, Ca, Mg, Al, Fe, Cr, Cu, Ni, Zn, Cd and Pb). The performance of green roof substrate prepared using perlite, vermiculite, sand, crushed brick, and coco-peat, was compared with local garden soil based on improvement of runoff quality. Portulaca grandiflora was used as green roof vegetation. Four different green roof configurations, with vegetated and non-vegetated systems, were examined for several artificial rain events (un-spiked and metal-spiked). In general, the vegetated green roof assemblies generated better-quality runoff with less conductivity and total metal ion concentration compared to un-vegetated assemblies. Of the different green roof configurations examined, P. grandiflora planted on green roof substrate acted as sink for various metals and showed the potential to generate better runoff. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Equivalent Thermal Resistance of Tile Roofs with and without Batten Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, William A

Clay and concrete tile roofs were installed on a fully instrumented attic test facility operating in East Tennessee s climate. Roof, attic and deck temperatures and heat flows were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventionally pigmented and direct-nailed asphalt shingle roof. The data were used to benchmark a computer tool for simulation of roofs and attics and the tool used to develop an approach for computing an equivalent seasonal R-value for sub-tile venting. The approach computed equal heat fluxes through the ceilings of roofs having different combinations ofmore » surface radiation properties and or building constructions. A direct nailed shingle roof served as a control for estimating the equivalent thermal resistance of the air space. Simulations were benchmarked to data in the ASHRAE Fundamentals for the thermal resistance of inclined and closed air spaces.« less

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)

Over the Top.

ERIC Educational Resources Information Center

American School & University, 1999

1999-01-01

Describes how careful preparation and having reliable information can make for a successful roofing project, whether retrofitting an old roof or topping off new construction. Contractor evaluation and warranty analysis are discussed. Also included is a roofing specifications chart for multi-ply and single-ply systems. (GR)

The influence of dual-substrate-layer extensive green roofs on rainwater runoff quantity and quality.

PubMed

Wang, Xiaoou; Tian, Yimei; Zhao, Xinhua

2017-08-15

This study investigates the ability of dual-substrate-layer extensive green roofs to retain rainwater and reduce pollutant leaching. The substrates in dual-substrate-layer green roofs consist of an upper organic nutrition layer for plant growth and a lower inorganic adsorption layer for water retention and pollutant reduction. One traditional single-substrate-layer extensive green roof was built for comparison with dual-substrate-layer green roofs. During the experimental period, dual-substrate-layer green roofs supported better natural vegetation growth, with coverage exceeding 90%, while the coverage in single-substrate-layer green roof was over 80%. Based on the average retention value of the total rainfall for four types of simulated rains (the total rainfall depth (mm) was 43.2, 54.6, 76.2 and 86.4, respectively), the dual-substrate-layer green roofs, which used the mixture of activated charcoal with perlite and vermiculite as the adsorption substrate, possessed better rainfall retention performance (65.9% and 55.4%) than the single-substrate-layer green roof (52.5%). All of the dual-substrate-layer green roofs appeared to be sinks for organics, heavy metals and all forms of nitrogen in all cases, while acted as sources of phosphorus contaminants in the case of heavy rains. In consideration of the factors of water retention, pollution reduction and service life of the green roof, a mixture of activated charcoal and/or pumice with perlite and vermiculite is recommended as the adsorption substrate. The green roofs were able to mitigate mild acid rain, raising the pH from approximately 5.6 in rainfall to 6.5-7.6 in green roof runoff. No signs of a first flush effect for phosphate, total phosphorus, ammonia nitrogen, nitrate nitrogen, total nitrogen, organics, zinc, lead, chromium, manganese, copper, pH or turbidity were found in the green roof runoff. Cost analysis further proved the practicability of dual-substrate-layer green roofs in retaining rainwater, and their long-term rainwater runoff quantity and quality performance in urban environments merit further investigation. Copyright © 2017 Elsevier B.V. All rights reserved.

Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ueno, Kohta; Lstiburek, Joseph W.

2015-09-01

Insulating roofs with dense-pack cellulose (instead of spray foam) has moisture risks, but is a lower cost approach. If moisture risks could be addressed, buildings could benefit from retrofit options, and the ability to bring HVAC systems within the conditioned space. Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except themore » vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. Some ridge sections were built as a conventional unvented roof, as a control. In the control unvented roofs, roof peak RHs reached high levels in the first winter; as exterior conditions warmed, RHs quickly fell. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).« less

Building America Case Study: Field Testing an Unvented Roof with Asphalt Shingles in a Cold Climate, Boilingbrook, Illinois

DOE Office of Scientific and Technical Information (OSTI.GOV)

2015-09-01

Insulating roofs with dense-pack cellulose (instead of spray foam) has moisture risks, but is a lower cost approach. If moisture risks could be addressed, buildings could benefit from retrofit options, and the ability to bring HVAC systems within the conditioned space. Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a 'control' vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except themore » vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a 'diffusion vent' detail, capped with vapor permeable roof membrane. Some ridge sections were built as a conventional unvented roof, as a control. In the control unvented roofs, roof peak RHs reached high levels in the first winter; as exterior conditions warmed, RHs quickly fell. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).« less

Smart Building. Volume 2: System Description

DTIC Science & Technology

2006-05-01

demonstrated.this technology at the 2002 Winter Olympic Games in Salt Lake City, Utah. The system was installed on a building known as Social Hall Plaza...select the detailed engineering contractors. 3.1.3.8 Sealing the Protective Envelope Due to the type of roof construction on the building there was ...in time to support the Olympics . Prototype testing was completed following the Olympics and additional testing may be performed to better

Experimental Polyvinyl Chloride (PVC) Roofing: Field Test Results.

DTIC Science & Technology

1987-02-01

construction. These were the single-ply membranes of the ethylene-propylene-diene monomer ( EPDM ) and polyvinyl chloride (PVC) types, and the sprayed-in-place...polyurethane foam (PUF) with an elastomeric coating. EPDM and PUF roofs were constructed in 19802 and the PVC roofs were completed during summer 1983...faced isocyanu- rate foam board in two layers . Roofing systems were installed loose-laid and ballasted. Specific membrane materials were Plymouth

Practical issues for using solar-reflective materials to mitigate urban heat islands

NASA Astrophysics Data System (ADS)

Bretz, Sarah; Akbari, Hashem; Rosenfeld, Arthur

Solar-reflective or high-albedo, alternatives to traditionally absorptive urban surfaces such as rooftops and roadways can reduce cooling energy use and improve urban air quality at almost no cost. This paper presents information to support programs that mitigate urban heat islands with solar-reflective surfaces: estimates of the achievable increase in albedo for a variety of surfaces, issues related to the selection of materials and costs and benefits of using them. As an example, we present data for Sacramento, California. In Sacramento, we estimate that 20% of the 96 square mile area is dark roofing and 10% is dark pavement. Based on the change in albedo that is achievable for these surfaces, the overall albedo of Sacramento could be increased by 18%, a change that would produce significant energy savings and increase comfort within the city. Roofing market data indicate which roofing materials should be targeted for incentive programs. In 1995, asphalt shingle was used for over 65% of residential roofing area in the U.S. and 6% of commercial. Built-up roofing was used for about 5% of residential roofing and about 30% of commercial roofing. Single-ply membranes covered about 9% of the residential roofing area and over 30% of the commercial area. White, solar-reflective alternatives are presently available for these roofing materials but a low- first-cost, solar-reflective alternative to asphalt shingles is needed to capture the sloped-roof market. Since incoming solar radiation has a large non-visible component, solar-reflective materials can also be produced in a variety of colors.

Survey of the Pagoda Timber Roof in Derneburg Castle

NASA Astrophysics Data System (ADS)

Perria, E.; Sieder, M.; Hoyer, S.; Krafczyk, C.

2017-05-01

The work analyses the historical roof of Derneburg Castle, in the municipality of Holle, Hildesheim's district, Lower Saxony, Germany. The roof is assembled according to Laves Balken's system (Laves beam's system), developed by the architect Georg Ludwig Friedrich Laves (1788-1864). The system has the peculiarity to consist of beams that are split along the half of the cross section, and maintained diverged by wooden wedges, distributed along the length of the beam. The system increases the height of the beam, and elevates the bending capacity of it (Weber, 1964). The work has been developed in the frame of an interdisciplinary project in the fields of architecture, engineering and photogrammetry. Main aim of the project is the developing of a structural model to understand the load-carrying capacity of Laves Balken's system from the laser-scanning model. For this reason, extensive surveys and photo documentation were collected on three areas of the roof construction, characterized by three peculiar usage of Laves Balken's system. The work presents the survey of the pagoda-roof that covers the tower of the castle, and problems that can be encountered during the survey of very complex timber constructions.

Construction of Experimental Roofing.

DTIC Science & Technology

1981-11-01

buildings at Fort Benning, GA; Fort Knox, KY; and Fort Lewis, WA. Sheets of EPDM synthetic rubber were installed on buildings at Forts Benning and Lewis...Contract and Unit Costs 14 5 Polyurethane Foam Roofing -- Initial Physical Properties 28 6 EPDM Sheet Rubber Roofing -- Initial Physical Properties 30 7...the new system. The system selected for Area A was an EPDM synthetic rubber manufactured by Carlisle Tire and Rubber Company. The contract specified

Leak Proof

ERIC Educational Resources Information Center

Steve, James

2005-01-01

Many school administrators protect their investments in new roofing systems by paying extra for an extended roof warranty. These warranties can be a valuable asset because they usually provide more coverage and reduce the school administrator's risk of having to pay for extensive roof repairs or replacements. Unfortunately, once an extended…

Solar heat collection with suspended metal roofing and whole house ventilation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maynard, T.

1996-10-01

A south pitched roof is employed for solar collection directly onto a roofing with chocolate brown color. The roofing is structural and is suspended over plywood decking so as to create an air space which receives input from the coolest and lowest basement air of the house interior. Air heated beneath the metal roofing is returned to a basement storage wall. Full length plenum cavities are formed into the ordinary rafter truss framing--at the knee wall and collar tie spaces. Preliminary testing of BTU gain at known air flows is acquired with a microprocessor system continuously collecting input and outputmore » temperatures at the roof collector into disk data files.« less

Use of fly-ash slurry in backfill grouting in coal mines.

PubMed

Jiang, Ning; Zhao, Jinhai; Sun, Xizhen; Bai, Liyang; Wang, Changxiang

2017-11-01

Cave backfill grouting implies grouting of the caving rock mass prior to it being compacted. The filling materials strengthen the caving rock and support the overlying strata to achieve the purpose of slowing down the surface subsidence. The broken roof will fail and collapse during mining operations performed without appropriate supporting measures being taken. It is difficult to perform continuous backfill mining on the working face of such roofs using the existing mining technology. In order to solve the above problems, fly ash and mine water are considered as filling materials, and flow characteristics of fly-ash slurry are investigated through laboratory experiments and theoretical analyses. Laws governing the diffusion of fly-ash slurry in the void of caving rock masses and in the void between a caving rock mass and a basic roof are obtained and verified. Based on the results obtained from the above analyses and actual conditions at the Zhaoguan coal mine, Shandong Province, China, a cave backfill grouting system of the hauling pipeline is developed and successfully tested at the 1703 working face in the Zhaoguan coal mine. The results demonstrate that a filling rate of 43.46% is achieved, and the surface subsidence coefficient of the grouting process is found to be 0.475. Compared to the total caving method, the proposed system is found to achieve a reduction rate of 40.63%. This effectively helps in lowering the value of the surface subsidence coefficient. Fly ash and mine water, considered as primary materials in this study, also play a significant role in improving the air quality and water environment.

11. INTERIOR OF ATTIC, VIEW FROM SOUTH END LOOKING AT ...

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

11. INTERIOR OF ATTIC, VIEW FROM SOUTH END LOOKING AT ROOF STRUCTURE ON EAST SIDE OF BUILDING. NOTE HEAVY TIMBER TRUSS SYSTEM WITH THIN, VERTICAL METAL SUPPORTS. THESE SUPPORTS WERE PROBABLY ADDED AFTER ALTERATIONS ON THE LOWER FLOORS IN THE LATE 1930s. THE PEELING PAINT ON THE TRUSS TIMBERS AND BEADED HORIZONTAL PANELING FURTHER INDICATES THAT THIS SPACE WAS FINISHED FOR USE AS A PRODUCTION AREA. - Graniteville Mill, Marshall Street, Graniteville, Aiken County, SC

Understanding green roof spatial dynamics: results from a scale based hydrologic study and introduction of a low-cost method for wide-range monitoring

NASA Astrophysics Data System (ADS)

Hakimdavar, Raha; Culligan, Patricia J.; Guido, Aida

2014-05-01

Green roofs have the potential, if implemented on a wide scale and with proper foresight, to become an important supplement to traditional urban water management infrastructure, while also helping to change the face of cities from concrete draped, highly modified environments, to hybrid places where nature is more closely integrated into designs rather than pushed out of them. The ability of these systems to act as a decentralized rainwater handling network has been the topic of many recent studies. While these studies have attempted to quantify the hydrologic performance of green roofs, it's clear that they are dynamic systems whose responses are difficult to generalize. What also seems to be lacking from many studies is a discussion on the effects of green roof scale, spatial planning and configuration. This research aims to understand how rainfall characteristics and green roof scale impact its hydrologic performance. Three extensive green roof systems in New York City, with the same engineered components, age and regional climatic conditions, but different drainage areas, are analyzed. We find that rainfall volume and event duration are two of the parameters that most affect green roof performance, while rainfall intensity and antecedent dry weather period are less significant. We also find that green roof scale does in fact affect hydrologic performance, but mainly in reducing runoff peaks, with rainfall retention and lag time being much less affected by drainage area. We also introduce a low-cost monitoring method, termed the Soil Water Apportioning (SWA) method, which uses a water balance approach to analytically link precipitation to substrate moisture, and enable inference of green runoff and evapotranspiration from information on substrate moisture changes over time. Twelve months of in situ rainfall and soil moisture observations from three different green roof systems - extensive vegetated mat, semi-intensive vegetated mat, and semi-intensive tray - are used to test the reliability of the proposed approach using two different low-cost soil moisture probes. The estimates of runoff are compared with observed runoff data for durations ranging between 6 months to 1 year. Preliminary results indicate that this can be an effective low-cost and low-maintenance alternative to the custom made weir and lysimeter systems frequently used to quantify runoff during green roof studies. By significantly reducing the cost and labor associated with typical monitoring efforts, the SWA method makes large scale studies of green roof hydrologic performance more feasible.

DART Support for Hurricane Matthew

NASA Image and Video Library

2016-10-13

Roofing materials, blown loose by Hurricane Matthew, are visible on the ground below the deck of the Beach House at NASA’s Kennedy Space Center in Florida. Members of the Disaster Assessment and Recovery Team (DART) are working on repairs to the facility following Hurricane Matthew, which passed to the east of Kennedy on Oct. 6 and 7, 2016. The center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected.

DART Support for Hurricane Matthew

NASA Image and Video Library

2016-10-13

Roofing materials, blown loose by Hurricane Matthew, lie on the ground behind the Beach House at NASA’s Kennedy Space Center in Florida. Members of the Disaster Assessment and Recovery Team (DART) are working on repairs to the facility following Hurricane Matthew, which passed to the east of Kennedy on Oct. 6 and 7, 2016. The center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected.

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

Duplex development and abandonment during evolution of the Lewis thrust system, southern Glacier National Park, Montana

NASA Astrophysics Data System (ADS)

Yin, An; Kelty, Thomas K.; Davis, Gregory A.

1989-09-01

Geologic mapping in southern Glacier National Park, Montana, reveals the presence of two duplexes sharing the same floor thrust fault, the Lewis thrust. The westernmost duplex (Brave Dog Mountain) includes the low-angle Brave Dog roof fault and Elk Mountain imbricate system, and the easternmost (Rising Wolf Mountain) duplex includes the low-angle Rockwell roof fault and Mt. Henry imbricate system. The geometry of these duplexes suggests that they differ from previously described geometric-kinematic models for duplex development. Their low-angle roof faults were preexisting structures that were locally utilized as roof faults during the formation of the imbricate systems. Crosscutting of the Brave Dog fault by the Mt. Henry imbricate system indicates that the two duplexes formed at different times. The younger Rockwell-Mt. Henry duplex developed 20 km east of the older Brave Dog-Elk Mountain duplex; the roof fault of the former is at a higher structural level. Field relations confirm that the low-angle Rockwell fault existed across the southern Glacier Park area prior to localized formation of the Mt. Henry imbricate thrusts beneath it. These thrusts kinematically link the Rockwell and Lewis faults and may be analogous to P shears that form between two synchronously active faults bounding a simple shear system. The abandonment of one duplex and its replacement by another with a new and higher roof fault may have been caused by (1) warping of the older and lower Brave Dog roof fault during the formation of the imbricate system (Elk Mountain) beneath it, (2) an upward shifting of the highest level of a simple shear system in the Lewis plate to a new decollement level in subhorizontal belt strata (= the Rockwell fault) that lay above inclined strata within the first duplex, and (3) a reinitiation of P-shear development (= Mt. Henry imbricate faults) between the Lewis thrust and the subparallel, synkinematic Rockwell fault.

Ventilation Processes in a Three-Dimensional Street Canyon

NASA Astrophysics Data System (ADS)

Nosek, Štěpán; Kukačka, Libor; Kellnerová, Radka; Jurčáková, Klára; Jaňour, Zbyněk

2016-05-01

The ventilation processes in three different street canyons of variable roof geometry were investigated in a wind tunnel using a ground-level line source. All three street canyons were part of an urban-type array formed by courtyard-type buildings with pitched roofs. A constant roof height was used in the first case, while a variable roof height along the leeward or windward walls was simulated in the two other cases. All street-canyon models were exposed to a neutrally stratified flow with two approaching wind directions, perpendicular and oblique. The complexity of the flow and dispersion within the canyons of variable roof height was demonstrated for both wind directions. The relative pollutant removals and spatially-averaged concentrations within the canyons revealed that the model with constant roof height has higher re-emissions than models with variable roof heights. The nomenclature for the ventilation processes according to quadrant analysis of the pollutant flux was introduced. The venting of polluted air (positive fluctuations of both concentration and velocity) from the canyon increased when the wind direction changed from perpendicular to oblique, irrespective of the studied canyon model. Strong correlations (>0.5) between coherent structures and ventilation processes were found at roof level, irrespective of the canyon model and wind direction. This supports the idea that sweep and ejection events of momentum bring clean air in and detrain the polluted air from the street canyon, respectively.

Career Directions--Renewable Energy Systems Integrator

ERIC Educational Resources Information Center

Fleeman, Stephen R.

2012-01-01

Renewable energy systems are beginning to appear everywhere. Solar modules are creating "blue roofs" that convert the energy from the sun into household electricity. Solar thermal systems on roofs can generate hot water. Wind turbines catch breezes to provide even more electricity. Recommendations for saving energy, specifying systems for…

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

The installation of green roofs, defined here as rooftops with a shallow soil cover and extensive vegetation, has been proposed as a possible measure to mitigate the loss of green space caused by the steady growth of cities. However, the effectiveness of green roofs in supporting arthropod communities, and the extent to which they facilitate connectivity of these communities within the urban environment is currently largely unknown. We investigated the variation of species community composition (beta diversity) of four arthropod groups with contrasting mobility (Carabidae, Araneae, Curculionidae, and Apidae) on 40 green roofs and 40 extensively managed green sites on the ground in the city of Zurich, Switzerland. With redundancy analysis and variation partitioning, we (1) disentangled the relative importance of local environmental conditions, the surrounding land cover composition, and habitat connectivity on species community composition, (2) searched for specific spatial scales of habitat connectivity for the different arthropod groups, and (3) discussed the ecological and functional value of green roofs in cities. Our study revealed that on green roofs community composition of high-mobility arthropod groups (bees and weevils) were mainly shaped by habitat connectivity, while low-mobility arthropod groups (carabids and spiders) were more influenced by local environmental conditions. A similar but less pronounced pattern was found for ground communities. The high importance of habitat connectivity in shaping high-mobility species community composition indicates that these green roof communities are substantially connected by the frequent exchange of individuals among surrounding green roofs. On the other hand, low-mobility species communities on green roofs are more likely connected to ground sites than to other green roofs. The integration of green roofs in urban spatial planning strategies has great potential to enable higher connectivity among green spaces, so 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.

The Role of Tectonic Stress in Triggering Large Silicic Caldera Eruptions

NASA Astrophysics Data System (ADS)

Cabaniss, Haley E.; Gregg, Patricia M.; Grosfils, Eric B.

2018-05-01

We utilize 3-D temperature-dependent viscoelastic finite element models to investigate the mechanical response of the host rock supporting large caldera-size magma reservoirs (volumes >102 km3) to local tectonic stresses. The mechanical stability of the host rock is used to determine the maximum predicted repose intervals and magma flux rates that systems may experience before successive eruption is triggered. Numerical results indicate that regional extension decreases the stability of the roof rock overlying a magma reservoir, thereby promoting early-onset caldera collapse. Alternatively, moderate amounts of compression (≤10 mm/year) on relatively short timescales (<104 years) increases roof rock stability. In addition to quantifying the affect of tectonic stresses on reservoir stability, our models indicate that the process of rejuvenation and mechanical failure is likely to take place over short time periods of hundreds to thousands of years. These findings support the short preeruption melt accumulation timescales indicated by U series disequilibrium studies.

ACHP | News | ACHP Issues Program Comment for GSA on Select Repairs and

Science.gov Websites

to windows, lighting, roofing, and heating, ventilating, and air-conditioning (HVAC) systems within Upgrades Windows Lighting Roofing Heating, Ventilation, and Air Conditioning (HVAC) Systems Updated March

12. October 1972. INTERIOR VIEW OF ROOF TRUSS SYSTEM. ...

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

12. October 1972. INTERIOR VIEW OF ROOF TRUSS SYSTEM. - Atlantic & Great Western Railroad, Meadville Repair Shops, Blacksmith Shop, East bank of French Creek, 800 feet South of Spring Street, Meadville, Crawford County, PA

"Conical Hut": A Basic Form of House Types in Timor Island

NASA Astrophysics Data System (ADS)

Chen, Y. R.; Lim, Y. L.; Wang, M. H.; Chen, C. Y.

2015-08-01

Timor Island situates in the southeast end of Southeast Asia. The island accommodates many ethnic groups, which produce many diverse house types. As visiting East Timor in 2012 and Timor Island in 2014, we found the "Pair- House Type" widely spread over Timor Island. Uma Lulik (holy house), accommodating the ancestry soul, fireplace and elder's bed, and Uma Tidor (house for sleep), containing living, sleeping and working space, compose the pair-house. The research team visited 14 ethnic groups and their houses, some of which were measured and drawn into 3D models as back to Taiwan. Uma Tidors of each ethnic group are quite similar with rectangular volume and hip roof, however, one of the fourteen ethnic groups can build cylinder houses for Uma Tidor. Uma Luliks of different ethnic groups are diversified and special. One group of the Uma Luliks shows a rectangular or square volume sheltered by a hip roof. The other group of Uma Luliks presents a non-specific volume under a conical roof, that we called the "conical hut". Seven ethnic groups, Atoni, Weimua, Makassae, Mambai, Bunaq, Kemak and Bekais, have built "conical huts" for the use of Uma Lulik. People of the seven ethnic groups can construct a reasonable structural system to support the conical roof, and take good advantage of the space under the conical roof to meet their sacred needs and everyday life. "Conical Hut" may be regarded as the basic form of the house types adopted by the seven ethnic groups. It contains the basic spatial limits and the formal properties that the construction systems have to follow. Based on the concise rules of the basic form, people of each ethnic group use their talents, skills and building materials to generate variations of "conical hut", which are different in house scale, spatial layout, construction system and form. The "conical huts" contain the consistency that all the huts come from the basic form, meanwhile, they also present the diversification that each conical hut has differed. "Consistent but diversified", is one of the most interesting issues in typological study that we can observe in Timorese houses.

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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. Themore » 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.« less

How To Choose the Right Roofing System.

ERIC Educational Resources Information Center

Carl, David

2001-01-01

Lists the factors that must be considered when specifying a roof for an existing or new facility. Factors discussed include cost, longevity, value of operations, warranties, building structure and design, and old vs. new system compatibility. (GR)

7. October 1972. INTERIOR VIEW, SHOWING THE ROOF TRUSS SYSTEM. ...

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

7. October 1972. INTERIOR VIEW, SHOWING THE ROOF TRUSS SYSTEM. - Atlantic & Great Western Railroad, Meadville Repair Shops, Blacksmith Shop, East bank of French Creek, 800 feet South of Spring Street, Meadville, Crawford County, PA

Supporting technology of roadside in gob-side entry in 110 longwall mining method

NASA Astrophysics Data System (ADS)

He, Manchao; Guo, Pengfei; Chen, Shangyuan; Gao, Yubing; Wang, Yajun

2017-05-01

To get better results of shaping roadside in 110 longwall mining method, the roadside support can be reasonably choose and designed through theoretical analysis, engineering test and other methods. The roadway support need to be designed based on the mining height and influence of mining pressure, and it is necessary to consider the "limited deformation" but also "given deformation". Because of the small mining high and short time under mining pressure effect in thin coal seam, roadside support can meet the requirements of block rock from gob using I-steel, but I-steel can't satisfy the deformation of roadway roof and easily lead to I-steel flexural buckling. In that condition we should use the U-steel that can compatible deformation with subsidence of roadway roof and enough torque in overlapping part between tow U-steel should be given when the U-steel is used to support gangue from gob and the U steel assembling two cards can coordinal deformation in dynamic pressure area keeping constant resistance with the deformation of roadway roof and can get a good effect. Through field test, due to the great impact force of the gangue from gob, single props and I-steel and U-steel are easily knocked down when the mining height is more than 4m. For large mining height, gangue blocking hydraulic support is designed and developed which can guarantee the stability and integrity of the roadway roof in the dynamic pressure area and can prevent the impact of gangue from gob. So it has better effect of forming roadway side using gangue from gob. According to above classification, the field experiments were carried out and obtained satisfactory results.

Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

2013-11-01

Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks formore » roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. This project directly investigated rain and indirectly investigated built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.« less

Starting Small, Thinking Big - Continuum Magazine | NREL

Science.gov Websites

field of urban science by preparing cities with world-class decision support. -Written by Kevin Eber How generation of clean energy decision science. Photo of two long cabins with a view of one roof, which is solar power systems to the grid in the U.S. Virgin Islands have led to a significant growth in installed

Interior, building 1205, view to west showing roof truss system, ...

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

Interior, building 1205, view to west showing roof truss system, 90 mm lens plus electronic flash fill lighting. - Travis Air Force Base, Readiness Maintenance Hangar, W Street, Air Defense Command Readiness Area, Fairfield, Solano County, CA

A 50 kilowatt distributed grid-connected photovoltaic generation system for the University of Wyoming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chowdhury, B.H.; Muknahallipatna, S.; Cupal, J.J.

The University of Wyoming (UW) campus is serving as the site for a 50 kilowatt solar photovoltaic (PV) system. Three sub-systems were sited and built on the UW campus in 1996. The first sub-system, a 10 kW roof-integrated system of PV roof tiles is located on the roof of the Engineering building. The second sub-system--a 5 kW rack-mounted, ballasted PV system is on a walkway roof of the Engineering building. The third sub-system is a 35 kW shade structure system and located adjacent to the parking lot of the university`s football stadium. The three sub-systems differ in their design strategymore » since each is being used for research and education at the university. Each sub-system, being located at some distance away from one another, supplies a different part of the campus grid. Efforts continue at setting up a central monitoring system which will receive data remotely from all locations. A part of this monitoring system is complete. While the initial monitoring data shows satisfactory performance, a number of reliability problems with PV modules and inverters have delayed full functionality of the system.« less

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 rights reserved.

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.

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.

The influence of extensive vegetated roofs on runoff water quality.

PubMed

Berndtsson, Justyna Czemiel; Emilsson, Tobias; Bengtsson, Lars

2006-02-15

The influence of extensive sedum-moss vegetated roofs on runoff water quality was studied for four full scale installations located in southern Sweden. The aim of the study was to ascertain whether the vegetated roof behaves as a sink or a source of pollutants and whether the age of a vegetated roof influences runoff quality. The runoff quality from vegetated roofs was also compared with the runoff quality from non-vegetated roofs located in study areas. The following metals and nutrients were investigated: Cd, Cr, Cu, Fe, K, Mn, Pb, Zn, NO3-N, NH4-N, Tot-N, PO4-P, and Tot-P. The results show that, with the exception of nitrogen, vegetated roofs behave as source of contaminants. While in lower concentrations than normally found in urban runoff, some metals appear in concentrations that would correspond to moderately polluted natural water. Nitrate nitrogen is retained by the vegetation or soil or both. Apart from the oldest, the studied vegetated roofs contribute phosphate phosphorus to the runoff. The maintenance of the vegetation systems on the roofs has to be carefully designed in order to avoid storm-water contamination; for instance, the use of easily dissolvable fertilizers should be avoided.

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.

Energy Efficient Florida Educational Facilities: Phase VI. Progress Report: Phase I and II.

ERIC Educational Resources Information Center

Callahan, Michael P.; Parker, Danny S.

A Florida study examined differences in energy uses in two adjacent portable classrooms to determine if these types of facilities can be made more energy efficient through retrofitting. Retrofitting included an efficient lighting system, new air conditioners, and reflective white metal roofs. Data show the white metal roofing reduced roof,…

30 CFR 75.1321 - Permits for firing more than 20 boreholes and for use of nonpermissible blasting units.

Code of Federal Regulations, 2011 CFR

2011-07-01

... approximate number of boreholes to be fired; (3) The period of time during which the permit will apply; (4..., track grading, roof brushing or boom holes; (5) A plan, proposed by the operator designed to protect... scaling and supporting the remaining roof prior to wiring a new series of boreholes; (2) Exposure to...

30 CFR 75.1321 - Permits for firing more than 20 boreholes and for use of nonpermissible blasting units.

Code of Federal Regulations, 2013 CFR

2013-07-01

... approximate number of boreholes to be fired; (3) The period of time during which the permit will apply; (4..., track grading, roof brushing or boom holes; (5) A plan, proposed by the operator designed to protect... scaling and supporting the remaining roof prior to wiring a new series of boreholes; (2) Exposure to...

30 CFR 75.1321 - Permits for firing more than 20 boreholes and for use of nonpermissible blasting units.

Code of Federal Regulations, 2010 CFR

2010-07-01

... approximate number of boreholes to be fired; (3) The period of time during which the permit will apply; (4..., track grading, roof brushing or boom holes; (5) A plan, proposed by the operator designed to protect... scaling and supporting the remaining roof prior to wiring a new series of boreholes; (2) Exposure to...

30 CFR 75.1321 - Permits for firing more than 20 boreholes and for use of nonpermissible blasting units.

Code of Federal Regulations, 2012 CFR

2012-07-01

... approximate number of boreholes to be fired; (3) The period of time during which the permit will apply; (4..., track grading, roof brushing or boom holes; (5) A plan, proposed by the operator designed to protect... scaling and supporting the remaining roof prior to wiring a new series of boreholes; (2) Exposure to...

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.

Experimental Polyurethane Foam Roof Systems - II.

DTIC Science & Technology

1983-01-01

distribution unlimited. qt’, B 11 1 A F FN 1 5.6,-’ ,". I Rf- IE I0 Edthat, I.f "" Roofs, energy conservation, insulation, sprayed polyurethane foam...pcriod is presented, and thle energy savings realized by Oamning thle roof’ are prese nted. Libirary Card Naval Civil lFiginvee.ig I alora tor)i...the energy savings I reali/ed by foaming the roof are presented.I Unclassified rC~U~tTY CL ASSIrICATIO)N OF THISt PAGi-h WI-., . I -d CONTENTS Page

Technology Solutions Case Study: Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2013-11-01

Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks formore » roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. In this project, Building Science Corporation investigated rain and built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.« less

Sedum-dominated green-roofs in a semi-arid region increase CO2 concentrations during the dry season.

PubMed

Agra, Har'el; Klein, Tamir; Vasl, Amiel; Shalom, Hadar; Kadas, Gyongyver; Blaustein, Leon

2017-04-15

Green roofs are expected to absorb and store carbon in plants and soils and thereby reduce the high CO 2 concentration levels in big cities. Sedum species, which are succulent perennials, are commonly used in extensive green roofs due to their shallow root system and ability to withstand long water deficiencies. Here we examined CO 2 fixation and emission rates for Mediterranean Sedum sediforme on green-roof experimental plots. During late winter to early spring, we monitored CO 2 concentrations inside transparent tents placed over 1m 2 plots and followed gas exchange at the leaf level using a portable gas-exchange system. We found high rates of CO 2 emission at daytime, which is when CO 2 concentration in the city is the highest. Both plot- and leaf-scale measurements showed that these CO 2 emissions were not fully compensated by the nighttime uptake. We conclude that although carbon sequestration may only be a secondary benefit of green roofs, for improving this ecosystem service, other plant species than Sedum should also be considered for use in green roofs, especially in Mediterranean and other semi-arid climates. Copyright © 2017 Elsevier B.V. All rights reserved.

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)

Radiation Insulation

NASA Technical Reports Server (NTRS)

1993-01-01

An aluminized polymer film is a highly effective radiation barrier for both manned and unmanned spacecraft. Variations of this space-devised material are also used as an energy conservation technique for homes and offices. One commercial company, Tech 2000 (formerly Buckeye Radiant Barrier), markets 'Super R' Radiant Barrier, which finds its origins in the Apollo Mission programs. The material is placed between wall studs and exterior facing before siding or in new roof installation, between roof support and roof sheathing. Successful retrofit installations have included schools and shrink wrap ovens. The radiant barrier blocks 95 percent of radiant energy, thus retaining summer heat and blocking winter cold. Suppliers claim utility bill reductions of 20 percent or more.

PowerGuard® manufacturing innovation and expansion

NASA Astrophysics Data System (ADS)

Dinwoodie, Thomas; Kleiner, Tim; O'Brien, Colleen; Quiroz, Maurice

1999-03-01

PowerLight Corporation, with support from the DOE's PVMaT program, has undertaken a comprehensive agenda to automate the manufacture of its PowerGuard PV roof tile system. The advanced manufacturing will lead to substantially reduced costs, quality improvements, and increased production capacity. Over the three years of the PVMaT contract, system costs are expected to fall 2.65/Wp, with annual production capability increasing from 5 to 16 MW. PowerLight is on schedule with meeting its objectives under this program.

On-site infiltration of a copper roof runoff: role of clinoptilolite as an artificial barrier material.

PubMed

Athanasiadis, Konstantinos; Helmreich, Brigitte; Horn, Harald

2007-08-01

On-site infiltration may be considered as a promising way of managing rainwater runoffs in urban areas, provided the hydrological and ecological conditions allow infiltration, and provided there is adequate treatment of the contaminants to avoid a risk of soil and groundwater pollution. The aim of this study was to evaluate the feasibility of the application of a new technical infiltration system equipped with clinoptilolite as an artificial barrier material for the treatment of the copper roof runoff of the Academy of Fine Arts in Munich, Germany. During the 2-yr sampling period, 30 rain events were examined. The cover material of the roof and the drainage system was responsible for the high copper concentrations in the roof runoff. The rain height and the rain intensity were of great significance regarding the establishment of the copper runoff rate. The technical infiltration system applied was able to reduce the copper from the roof runoff by a factor up to 96%. The mean measured copper concentration in percolation water was lower than the critical value of 50 microg/l set by the German Federal Soil Protection Act and Ordinance, indicating no risk for soil and groundwater contamination.

76 FR 25704 - Announcement of Funding Awards for the Emergency Capital Repair Grant Program; Fiscal Year 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-05

.......... PA 12 251,953 Replace windows, emergency call system, elevators and roof. Culpepper Garden I Culpepper Garden I, Inc. Arlington VA 204 447,071 Replace the convertor system tees and piping. DePaul House............ NC 75 272,210 Replace the roofs and correct the failed drainage system. Highlands Manor National...

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.

Edge Supports for Photovoltaic Modules

NASA Technical Reports Server (NTRS)

Maloney, T. J.

1984-01-01

Mounting strips patterned after glazing gaskets. Easy to install supports for rooftop solar modules consist of extruded rubber mullions with locking zippers. Supports cut to length with utility knife and installed without special tools. Adaptable to many different roof configurations.

Cladonia lichens on extensive green roofs: evapotranspiration, substrate temperature, and albedo.

PubMed

Heim, Amy; Lundholm, Jeremy

2013-01-01

Green roofs are constructed ecosystems that provide ecosystem services in urban environments. Shallow substrate green roofs subject the vegetation layer to desiccation and other environmental extremes, so researchers have evaluated a variety of stress-tolerant vegetation types for green roof applications. Lichens can be found in most terrestrial habitats.  They are able to survive extremely harsh conditions, including frequent cycles of desiccation and rehydration, nutrient-poor soil, fluctuating temperatures, and high UV intensities. Extensive green roofs (substrate depth <20cm) exhibit these harsh conditions, making lichens possible candidates for incorporation into the vegetation layer on extensive green roofs.  In a modular green roof system, we tested the effect of Cladonia lichens on substrate temperature, water loss, and albedo compared to a substrate-only control. Overall, the Cladonia modules had significantly cooler substrate temperatures during the summer and significantly warmer temperatures during the fall.  Additionally, the Cladonia modules lost significantly less water than the substrate-only control. This implies that they may be able to benefit neighboring vascular plant species by reducing water loss and maintaining favorable substrate temperatures.

Mean-variance portfolio analysis data for optimizing community-based photovoltaic investment.

PubMed

Shakouri, Mahmoud; Lee, Hyun Woo

2016-03-01

The amount of electricity generated by Photovoltaic (PV) systems is affected by factors such as shading, building orientation and roof slope. To increase electricity generation and reduce volatility in generation of PV systems, a portfolio of PV systems can be made which takes advantages of the potential synergy among neighboring buildings. This paper contains data supporting the research article entitled: PACPIM: new decision-support model of optimized portfolio analysis for community-based photovoltaic investment [1]. We present a set of data relating to physical properties of 24 houses in Oregon, USA, along with simulated hourly electricity data for the installed PV systems. The developed Matlab code to construct optimized portfolios is also provided in . The application of these files can be generalized to variety of communities interested in investing on PV systems.

7. COOLING TOWER FROM ROOF. Hot Springs National Park, ...

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

7. COOLING TOWER FROM ROOF. - Hot Springs National Park, Bathhouse Row, Quapaw Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

29 CFR Appendix A to Subpart M of... - Determining Roof Widths

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Fall Protection Pt. 1926... monitoring system alone as a means of providing fall protection during the performance of roofing operations...

29 CFR Appendix A to Subpart M of... - Determining Roof Widths

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Fall Protection Pt. 1926... monitoring system alone as a means of providing fall protection during the performance of roofing operations...

29 CFR Appendix A to Subpart M of... - Determining Roof Widths

Code of Federal Regulations, 2010 CFR

2010-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Fall Protection Pt. 1926... monitoring system alone as a means of providing fall protection during the performance of roofing operations...

29 CFR Appendix A to Subpart M of... - Determining Roof Widths

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Fall Protection Pt. 1926... monitoring system alone as a means of providing fall protection during the performance of roofing operations...

29 CFR Appendix A to Subpart M of... - Determining Roof Widths

Code of Federal Regulations, 2011 CFR

2011-07-01

..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Fall Protection Pt. 1926... monitoring system alone as a means of providing fall protection during the performance of roofing operations...

Investigation to Identify Performance Criteria and Test Methods for Evaluating Single-Ply Roofing Systems.

DTIC Science & Technology

1987-03-01

Reinforced Black EPDM Rubber Sheets for Use in Roofing Applications ( Rubber Manufacturers Association [RMAJ, 1984). Minimum Requirements for Fabric-Reinforced...Black Polychloroprene Rubber Sheets for Use in Roofing Applications (RMA, 1984). Minimum Requirements for Non-Reinforced Black EPDM Rubber Sheets for...and materials. The Rubber Manufacturers Amoeiation (RMA) (USA) RMA is funding a study in conjunction with ASTM to evaluate three different EPDM

41. Interior view of roof and wall below, looking to ...

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

41. Interior view of roof and wall below, looking to the east from the second floor landing at the junction of the common rafters to the raising plate, or false plate (note the false plate does not rest on the brick wall, instead is lapped over tie beams that support the floor & framing of the second level) - Kiskiack, Naval Mine Depot, State Route 238 vicinity, Yorktown, York County, VA

Rock bolt overload warning device

DOE Office of Scientific and Technical Information (OSTI.GOV)

Unrug, K.F.

1983-10-18

A washer is described which is used in the construction of the support for the roof of a mine. The washer is fabricated such that finger like projections rupture in stages as the tension on bolts and pressure in the strata of the roof of the mine increases beyond structurely safe limits. The rupturing of the washer emits audible warning signals and also provides a visual indication of an unsafe condition.

Green roof seasonal variation: comparison of the hydrologic behavior of a thick and a thin extensive system in New York City

NASA Astrophysics Data System (ADS)

Elliott, R. M.; Gibson, R. A.; Carson, T. B.; Marasco, D. E.; Culligan, P. J.; McGillis, W. R.

2016-07-01

Green roofs have been utilized for urban stormwater management due to their ability to capture rainwater locally. Studies of the most common type, extensive green roofs, have demonstrated that green roofs can retain significant amounts of stormwater, but have also shown variation in seasonal performance. The purpose of this study is to determine how time of year impacts the hydrologic performance of extensive green roofs considering the covariates of antecedent dry weather period (ADWP), potential evapotranspiration (ET0) and storm event size. To do this, nearly four years of monitoring data from two full-scale extensive green roofs (with differing substrate depths of 100 mm and 31 mm) are analyzed. The annual performance is then modeled using a common empirical relationship between rainfall and green roof runoff, with the addition of Julian day in one approach, ET0 in another, and both ADWP and ET0 in a third approach. Together the monitoring and modeling results confirm that stormwater retention is highest in warmer months, the green roofs retain more rainfall with longer ADWPs, and the seasonal variations in behavior are more pronounced for the roof with the thinner media than the roof with the deeper media. Overall, the ability of seasonal accounting to improve stormwater retention modeling is demonstrated; modification of the empirical model to include ADWP, and ET0 improves the model R 2 from 0.944 to 0.975 for the thinner roof, and from 0.866 to 0.870 for the deeper roof. Furthermore, estimating the runoff with the empirical approach was shown to be more accurate then using a water balance model, with model R 2 of 0.944 and 0.866 compared to 0.975 and 0.866 for the thinner and deeper roof, respectively. This finding is attributed to the difficulty of accurately parameterizing the water balance model.

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. Copyright © 2011 Elsevier Ltd. All rights reserved.

Establishment and performance of an experimental green roof under extreme climatic conditions.

PubMed

Klein, Petra M; Coffman, Reid

2015-04-15

Green roofs alter the surface energy balance and can help in mitigating urban heat islands. However, the cooling of green roofs due to evapotranspiration strongly depends on the climatic conditions, and vegetation type and density. In the Southern Central Plains of the United States, extreme weather events, such as high winds, heat waves and drought conditions pose challenges for successful implementation of green roofs, and likely alter their standard performance. The National Weather Center Experimental Green Roof, an interdisciplinary research site established in 2010 in Norman, OK, aimed to investigate the ecological performance and surface energy balance of green roof systems. Starting in May 2010, 26 months of vegetation studies were conducted and the radiation balance, air temperature, relative humidity, and buoyancy fluxes were monitored at two meteorological stations during April-October 2011. The establishment of a vegetative community trended towards prairie plant dominance. High mortality of succulents and low germination of grasses and herbaceous plants contributed to low vegetative coverage. In this condition succulent diversity declined. Bouteloua gracilis and Delosperma cooperi showed typological dominance in harsh climatic conditions, while Sedum species experienced high mortality. The plant community diversified through volunteers such as Euphorbia maculate and Portulaca maculate. Net radiation measured at a green-roof meteorological station was higher than at a control station over the original, light-colored roofing material. These findings indicate that the albedo of the green roof was lower than the albedo of the original roofing material. The low vegetative coverage during the heat and drought conditions in 2011, which resulted in the dark substrate used in the green roof containers being exposed, likely contributed to the low albedo values. Nevertheless, air temperatures and buoyancy fluxes were often lower over the green roof indicating that higher evapotranspiration rates compensated for the higher net radiation at the green roof. Copyright © 2015 Elsevier B.V. All rights reserved.

20. Photographic copy of photograph of roof suspender system taken ...

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

20. Photographic copy of photograph of roof suspender system taken on March 22, 1957. Photographer unknown. Original photograph property of the City of Philadelphia, Division of Aviation. Reprinted with permission of the Division of Aviation. - TWA Maintenance Hangar, South side of Tinicum Island Road, Philadelphia International Airport, Philadelphia, Philadelphia County, PA

Interior, building 1205, view to southeast showing roof truss system, ...

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

Interior, building 1205, view to southeast showing roof truss system, sliding main doors, and roll up door at center to allow clearance for aircraft tail assembly, 90 mm lens plus electronic flash fill lighting. - Travis Air Force Base, Readiness Maintenance Hangar, W Street, Air Defense Command Readiness Area, Fairfield, Solano County, CA

Terrestrial Photovoltaic System Analysis.

DTIC Science & Technology

1980-07-01

the photovoltaic arrays was detertttined to be the roof on the building adjacent to the plating facilit.. Sult ficitut roof area is available to...indicated here: Component 50 kW System 300 kW System Solar Array $10/W $"’/W Inverter $38/W $I/W (dlitereut supplier) The life-cycle cost analysis...27 15. Various solar energy concem t rating systems .......... 3 I. Varionts photovoltaic concentrators developed under PRDA- 15

Oblique Photogrammetry Supporting 3d Urban Reconstruction of Complex Scenarios

NASA Astrophysics Data System (ADS)

Toschi, I.; Ramos, M. M.; Nocerino, E.; Menna, F.; Remondino, F.; Moe, K.; Poli, D.; Legat, K.; Fassi, F.

2017-05-01

Accurate 3D city models represent an important source of geospatial information to support various "smart city" applications, such as space management, energy assessment, 3D cartography, noise and pollution mapping as well as disaster management. Even though remarkable progress has been made in recent years, there are still many open issues, especially when it comes to the 3D modelling of complex urban scenarios like historical and densely-built city centres featuring narrow streets and non-conventional building shapes. Most approaches introduce strong building priors/constraints on symmetry and roof typology that penalize urban environments having high variations of roof shapes. Furthermore, although oblique photogrammetry is rapidly maturing, the use of slanted views for façade reconstruction is not completely included in the reconstruction pipeline of state-of-the-art software. This paper aims to investigate state-of-the-art methods for 3D building modelling in complex urban scenarios with the support of oblique airborne images. A reconstruction approach based on roof primitives fitting is tested. Oblique imagery is then exploited to support the manual editing of the generated building models. At the same time, mobile mapping data are collected at cm resolution and then integrated with the aerial ones. All approaches are tested on the historical city centre of Bergamo (Italy).

Sealed rotary hearth furnace with central bearing support

DOEpatents

Docherty, James P.; Johnson, Beverly E.; Beri, Joseph

1989-01-01

The furnace has a hearth which rotates inside a stationary closed chamber and is supported therein on vertical cylindrical conduit which extends through the furnace floor and is supported by a single center bearing. The charge is deposited through the furnace roof on the rim of the hearth as it rotates and is moved toward the center of the hearth by rabbles. Externally generated hot gases are introduced into the furnace chamber below the hearth and rise through perforations in the hearth and up through the charge. Exhaust gases are withdrawn through the furnace roof. Treated charge drops from a center outlet on the hearth into the vertical cylindrical conduit which extends downwardly through the furnace floor to which it is also sealed.

Structural Code Considerations for Solar Rooftop Installations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dwyer, Stephen F.; Dwyer, Brian P.; Sanchez, Alfred

2014-12-01

Residential rooftop solar panel installations are limited in part by the high cost of structural related code requirements for field installation. Permitting solar installations is difficult because there is a belief among residential permitting authorities that typical residential rooftops may be structurally inadequate to support the additional load associated with a photovoltaic (PV) solar installation. Typical engineering methods utilized to calculate stresses on a roof structure involve simplifying assumptions that render a complex non-linear structure to a basic determinate beam. This method of analysis neglects the composite action of the entire roof structure, yielding a conservative analysis based on amore » rafter or top chord of a truss. Consequently, the analysis can result in an overly conservative structural analysis. A literature review was conducted to gain a better understanding of the conservative nature of the regulations and codes governing residential construction and the associated structural system calculations.« less

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 a rooftop? 2) How does this design compare with the performance of the extant Green Grid green roof system on the roof in regard to storm water runoff mitigation and nutrient leaching? and 3) Using GIS, can this information be scaled to a larger region (i.e. UNH campus, the NH Seacoast, NH cities, etc.) to determine areas of particular interest for pollinator conservation? Runoff mitigation, as a percentage of precipitation, is expected to be greater than that on the roof with proprietary substrate, though nutrient leaching may be greater as well due to the higher organic matter content. Paired with GIS data on NH ecoregions, these results will help to identify areas in the state that would benefit from the construction of pollinator habitat corridors, including urban areas that may not have been previously considered.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Jiachen; Zhang, Kai; Liu, Junfeng

Solar reflective “cool roofs” absorb less sunlight than traditional dark roofs, reducing solar heat gain, and decreasing the amount of heat transferred to the atmosphere. Widespread adoption of cool roofs could therefore reduce temperatures in urban areas, partially mitigating the urban heat island effect, and contributing to reversing the local impacts of global climate change. The impacts of cool roofs on global climate remain debated by past research and are uncertain. Using a sophisticated Earth system model, the impacts of cool roofs on climate are investigated at urban, continental, and global scales. We find that global adoption of cool roofsmore » in urban areas reduces urban heat islands everywhere, with an annual- and global-mean decrease from 1.6 to 1.2 K. Decreases are statistically significant, except for some areas in Africa and Mexico where urban fraction is low, and some high-latitude areas during wintertime. Analysis of the surface and TOA energy budget in urban regions at continental-scale shows cool roofs causing increases in solar radiation leaving the Earth-atmosphere system in most regions around the globe, though the presence of aerosols and clouds are found to partially offset increases in upward radiation. Aerosols dampen cool roof-induced increases in upward solar radiation, ranging from 4% in the United States to 18% in more polluted China. Adoption of cool roofs also causes statistically significant reductions in surface air temperatures in urbanized regions of China (0.11±0.10 K) and the United States (0.14±0.12 K); India and Europe show statistically insignificant changes. The research presented here indicates that adoption of cool roofs around the globe would lead to statistically insignificant reductions in global mean air temperature (0.0021 ±0.026 K). This counters past research suggesting that cool roofs can reduce, or even increase global mean temperatures. Thus, we suggest that while cool roofs are an effective tool for reducing building energy use in hot climates, urban heat islands, and regional air temperatures, their influence on global climate is likely negligible.« less

In-Depth Analysis of Simulation Engine Codes for Comparison with DOE s Roof Savings Calculator and Measured Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

New, Joshua Ryan; Levinson, Ronnen; Huang, Yu

The Roof Savings Calculator (RSC) was developed through collaborations among Oak Ridge National Laboratory (ORNL), White Box Technologies, Lawrence Berkeley National Laboratory (LBNL), and the Environmental Protection Agency in the context of a California Energy Commission Public Interest Energy Research project to make cool-color roofing materials a market reality. The RSC website and a simulation engine validated against demonstration homes were developed to replace the liberal DOE Cool Roof Calculator and the conservative EPA Energy Star Roofing Calculator, which reported different roof savings estimates. A preliminary analysis arrived at a tentative explanation for why RSC results differed from previous LBNLmore » studies and provided guidance for future analysis in the comparison of four simulation programs (doe2attic, DOE-2.1E, EnergyPlus, and MicroPas), including heat exchange between the attic surfaces (principally the roof and ceiling) and the resulting heat flows through the ceiling to the building below. The results were consolidated in an ORNL technical report, ORNL/TM-2013/501. This report is an in-depth inter-comparison of four programs with detailed measured data from an experimental facility operated by ORNL in South Carolina in which different segments of the attic had different roof and attic systems.« less

Hydrological performance of extensive green roofs in New York City: observations and multi-year modeling of three full-scale systems

NASA Astrophysics Data System (ADS)

Carson, T. B.; Marasco, D. E.; Culligan, P. J.; McGillis, W. R.

2013-06-01

Green roofs can be an attractive strategy for adding perviousness in dense urban environments where rooftops are a high fraction of the impervious land area. As a result, green roofs are being increasingly implemented as part of urban stormwater management plans in cities around the world. In this study, three full-scale green roofs in New York City (NYC) were monitored, representing the three extensive green roof types most commonly constructed: (1) a vegetated mat system installed on a Columbia University residential building, referred to as W118; (2) a built-in-place system installed on the United States Postal Service (USPS) Morgan general mail facility; and (3) a modular tray system installed on the ConEdison (ConEd) Learning Center. Continuous rainfall and runoff data were collected from each green roof between June 2011 and June 2012, resulting in 243 storm events suitable for analysis ranging from 0.25 to 180 mm in depth. Over the monitoring period the W118, USPS, and ConEd roofs retained 36%, 47%, and 61% of the total rainfall respectively. Rainfall attenuation of individual storm events ranged from 3 to 100% for W118, 9 to 100% for USPS, and 20 to 100% for ConEd, where, generally, as total rainfall increased the per cent of rainfall attenuation decreased. Seasonal retention behavior also displayed event size dependence. For events of 10-40 mm rainfall depth, median retention was highest in the summer and lowest in the winter, whereas median retention for events of 0-10 mm and 40 +mm rainfall depth did not conform to this expectation. Given the significant influence of event size on attenuation, the total per cent retention during a given monitoring period might not be indicative of annual rooftop retention if the distribution of observed event sizes varies from characteristic annual rainfall. To account for this, the 12 months of monitoring data were used to develop a characteristic runoff equation (CRE), relating runoff depth and event size, for each green roof. When applied to Central Park, NYC precipitation records from 1971 to 2010, the CRE models estimated total rainfall retention over the 40 year period to be 45%, 53%, and 58% for the W118, USPS, and ConEd green roofs respectively. Differences between the observed and modeled rainfall retention for W118 and USPS were primarily due to an abnormally high frequency of large events, 50 mm of rainfall or more, during the monitoring period compared to historic precipitation patterns. The multi-year retention rates are a more reliable estimate of annual rainfall capture and highlight the importance of long-term evaluations when reporting green roof performance.

Solar Air Heating Metal Roofing for Reroofing, New Construction, and Retrofit

DTIC Science & Technology

2013-05-20

roof is installed starting the cycle over again. In contrast, metal roofing has a nominal service life of 40 years, can be recycled when removed and...energy, recycled content, innovation, air quality and other elements. American Solar intends to target trade publications, websites, and speaking...insulation with cloth jacket covered the bottom of the metal deck. The schematic Figure A-2, 3, shows the system as proposed at the

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.

Winnebago Tribe Solar Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nieman, Autumn

2016-02-26

The strategy of the Solar Project was to reduce fuel use within two years by a roof mounted photovoltaic system. The police/fire building is completely powered by electricity. The renewable energy system we have selected has a power capacity of 23kW and the ability to export 44.3 MWh. We anticipate 32.55% kWh energy savings, an excess of the required 30% reduction, in the building’s total fuel use based on the most current 12 months of data (2012). The solar electric system is a grid-tie, ballast mounted on a flat roof over the police/fire station. The solar electric system includes 280more » Watt modules for a nominal total of 22.80 kW. Approximately 84 modules are ballast mounted to the flat roof facing south.« less

Plant Operation: Exterior Maintenance, Work Hours

ERIC Educational Resources Information Center

Nation's Schools and Colleges, 1975

1975-01-01

A pitched roof built over a flat roof prevented leaking at a Vermont school. The University of New Hampshire paint shop has a flexible scheduling system that allows employees to choose their work hours each day. (Author/MLF)

Design of a photovoltaic system for a southeast all-electric residence

NASA Astrophysics Data System (ADS)

Mehalick, E. M.; Tully, G. F.; Johnson, J.; Truncellito, N.; Schaeffer, R.; Parker, J.

1982-01-01

A photovoltaic system was developed and integrated into a single-story residence suitable for the Southeast region of the country. The design addresses an integral mounted array which displaces conventional roof sheathing, roofing felt and shingles. The array has a rated power output of 5.6 kW and covers 86 sq.m. of roof area. A 6 kW utility-tied inverter is used in the power conversion subsystem, representative of a lower cost version, currently available hardware. The system provides feedback of excess energy to the utility, which is the most promising approach for grid-connected systems in the mid-1980's. The complete system and house design are described, including all the pertinent installation and construction drawings. Specific performance results are presented for the Miami, Florida, and Charleston, SC, regions.

Application of Composite Indices for Improving Joint Detection Capabilities of Instrumented Roof Bolt Drills in Underground Mining and Construction

NASA Astrophysics Data System (ADS)

Liu, Wenpeng; Rostami, Jamal; Elsworth, Derek; Ray, Asok

2018-03-01

Roof bolts are the dominant method of ground support in mining and tunneling applications, and the concept of using drilling parameters from the bolter for ground characterization has been studied for a few decades. This refers to the use of drilling data to identify geological features in the ground including joints and voids, as well as rock classification. Rock mass properties, including distribution of joints/voids and strengths of rock layers, are critical factors for proper design of ground support to avoid instability. The goal of this research was to improve the capability and sensitivity of joint detection programs based on the updated pattern recognition algorithms in sensing joints with smaller than 3.175 mm (0.125 in.) aperture while reducing the number of false alarms, and discriminating rock layers with different strengths. A set of concrete blocks with different strengths were used to simulate various rock layers, where the gap between the blocks would represent the joints in laboratory tests. Data obtained from drilling through these blocks were analyzed to improve the reliability and precision of joint detection systems. While drilling parameters can be used to detect the gaps, due to low accuracy of the results, new composite indices have been introduced and used in the analysis to improve the detection rates. This paper briefly discusses ongoing research on joint detection by using drilling parameters collected from a roof bolter in a controlled environment. The performances of the new algorithms for joint detection are also examined by comparing their ability to identify existing joints and reducing false alarms.

Structural Element Tests in Support of the Keyworker Blast Shelter Program

DTIC Science & Technology

1985-10-01

forced concrete -lab with two transverse reinforced concrete floor beams to transfer the interior column loads to the floor slab. Using a roof slab... lateral buck- "-4 ling; however, this could have occurred after a column buckled and the roof collapsed. Since load cell 2 (middle column ) recorded the...ANALYSIS OF FREE-FIELD AND STRUCTURE LOADING DATA ... ........ .. 102 6.1.1 Loading Wave Velocity ........... .................... ... 102 6.1.2 Lateral

8. Detail, west corner, showing entrance fenestration, carved rafters supporting ...

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

8. Detail, west corner, showing entrance fenestration, carved rafters supporting metal-tiled pent roofs, tinted mortar; view to east. - Larco Building, 214 State Street, Santa Barbara, Santa Barbara County, CA

Volcanic ashfall accumulation and loading on gutters and pitched roofs from laboratory empirical experiments: Implications for risk assessment

NASA Astrophysics Data System (ADS)

Hampton, S. J.; Cole, J. W.; Wilson, G.; Wilson, T. M.; Broom, S.

2015-10-01

Volcanic ash load is dependent on the migration and accumulation of ash on roofing surfaces and guttering, of which limited research has been conducted. This study investigates this knowledge gap through the empirical experimental testing of volcanic ash on variably pitched metal sheet roofs with modern PVC gutter systems, highlighting the relative importance of accumulation, migration, remobilization, saturation, and subsequent load. A testing rig delivered ash onto variably pitched roofs (pitches 15°, 25°, 30°, 35°, and 45°) with two 45° tests involving a wet surface with subsequent ashfall, and the second of ashfall with periods of wetting, followed by wetting until failure. In testing, dry ash on a dry roof accumulates at pitches up to 35°, above this pitch the percentage of ash accumulating reduces with greater percentages infilling guttering and or lost to the ground. With the introduction of a wet roof surface at 45° pitch, adherence of dry ash greatly increases, increasing accumulated ash thickness as compared to dry tests from 8% to 38%. For testing involving periods of wetting at 45° roof pitch, accumulation percentages further increased to 50%. Ash migrating from the roof surface filled guttering more rapidly at greater pitches, which once full resulted in further migrating ash to spill over the front or back gutter lips. Collapse of guttering did not occur during testing, but deformation and bracket detachment did occur at loads > 1 kPa. This study provides data on load calculations on roofing and PVC guttering through the quantification and utilization of relationships between ash fate, pitch, and the influence of water, in the development of two scenarios for both roof and gutter. These two scenarios then enable the estimation of ash accumulation and thus the load and collapse thresholds for roof and gutter at different roof pitch, which could be adopted for volcanic risk modeling or risk management.

57. Photocopy of Architectural Layout drawing, dated 25 June, 1993 ...

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

57. Photocopy of Architectural Layout drawing, dated 25 June, 1993 by US Air Force Space Command. Original drawing property of United States Air Force, 21" Space Command. AL-3 PAVE PAWS SUPPORT SYSTEMS - CAPE COD AFB, MASSACHUSETTS - LAYOUT 1 FLOOR AND 1sr FLOOR ROOF. DRAWING NO. AL-3 - SHEET 4 OF 21. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

Solar Energy Investigation Activities for Primary Pupils: Experience Sharing from a Teacher of a Solar Energy School in Hong Kong

ERIC Educational Resources Information Center

Cho, Kit Fan

2005-01-01

CCC Kei Wai Primary School (Ma Wan) is a 30-classroom 7-story primary school located at Ma Wan Island. The campus was completed in 2003. There are three arrays of photovoltaic modules installed on the roof with an expected annual yield of 5600 kWh a.c. electricity. This system is supported by a research project called "Building Integrated…

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 metalmore » 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].« less

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.

KSC-2013-2689

NASA Image and Video Library

2013-06-12

CAPE CANAVERAL, Fla. – At Launch Pad 39B at NASA’s Kennedy Space Center in Florida, crawler track panels have been removed from the surface and construction workers are repairing the concrete surface and catacomb roof below. Launch Pad 39B is being refurbished to support NASA’s Space Launch System and other launch vehicles. The Ground Systems Development and Operations, or GSDO, Program office at Kennedy is leading the center’s transformation to safely handle a variety of rockets and spacecraft. For more information about GSDO, visit: http://go.nasa.gov/groundsystems. Photo credit: NASA/Jim Grossman

4. EXTERIOR VIEW OF HILLMAN FAN HOUSE LOOKING NORTHEAST This ...

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

4. EXTERIOR VIEW OF HILLMAN FAN HOUSE LOOKING NORTHEAST This view shows the concrete roof covering the airways and the engine room. The reinforced concrete roof is supported by metal beams. Note how the airshaft, in the foreground, widens to create an airway on either side for the double inlet fan. The brick fan housing is capped by a curved sheet metal roof whose segments are bolted together. The brick updraft chimney, capped with concrete, is to the rear (northeast). Also evident on the wall is the cover over the air velocity indicator. The Hollenback Cemetery, which adjoins the Dorrance Colliery property is in the background. - Dorrance Colliery Fan Complex, South side of Susquehanna River at Route 115 & Riechard Street, Wilkes-Barre, Luzerne County, PA

Mean-variance portfolio analysis data for optimizing community-based photovoltaic investment

PubMed Central

Shakouri, Mahmoud; Lee, Hyun Woo

2016-01-01

The amount of electricity generated by Photovoltaic (PV) systems is affected by factors such as shading, building orientation and roof slope. To increase electricity generation and reduce volatility in generation of PV systems, a portfolio of PV systems can be made which takes advantages of the potential synergy among neighboring buildings. This paper contains data supporting the research article entitled: PACPIM: new decision-support model of optimized portfolio analysis for community-based photovoltaic investment [1]. We present a set of data relating to physical properties of 24 houses in Oregon, USA, along with simulated hourly electricity data for the installed PV systems. The developed Matlab code to construct optimized portfolios is also provided in Supplementary materials. The application of these files can be generalized to variety of communities interested in investing on PV systems. PMID:26937458

ROOFER Inventory Procedures and Inspection Manual for Metal Panel Roofing

DTIC Science & Technology

2012-12-01

impedes drainage . 2. Flashing has holes. 3. Flashing joint has failed and is allowing water to penetrate the roofing system . 4. Flashing flange... system shares a number of general characteristics with other types, but they use certain distinct types of materials that have their own... System . DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does

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 influence green roof functions.

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 evidence that plant composition and diversity can influence green roof functions. PMID:21292676

Experiences from full-scale rockfall testing of protection gallery

NASA Astrophysics Data System (ADS)

Volkwein, Axel; Fergg, Daniel; Hess, Reto; Schellenberg, Kristian

2017-04-01

Vertical drop tests have been performed at the Swiss Oberalppass road. The planned deconstruction of two avalanche protection galleries enabled a precedent evaluation of one gallery (Parde 1} regarding its capacity against rockfall. The background for this evaluation was also to evaluate an existing model for predicting the protection capacity of a rockfall gallery. Based on this model existing galleries can be evaluated whether their residual capacity is sufficient or if it is necessary to strengthen the structureaccording to the current guidelines. This contribution focusses the conduction of the experiments and the experiences obtained from. The presentation gives details on experimental setup, impact characterization, gallery performance, weather implications, data retrieval and data analysis.According to the limited time span for testing and the resources available, a compact testing series has been setup. Three fields of the gallery were tested with drop weights of 800, 1600 and 3200 kg falling from up to 25 m height. The blocks were lifted by a mobil crane. The concrete roof is supported by columns on the valley side and on the mountainside simply supported on the retention wall. The roof slabspans approximately 6x5 m with a thickness of about 0.60 m and is covered by a soil cushion, which has been unified to 0.40 m thickness previous to the test. Additional wooden columns have been installed at the roof's valleyside to avoid a failure of the concrete columns and to favorize a failure of the roof itself due to bending or punching. The measurements performed consist of high speed video records, accelerations within the impactors and on the bottom surface of the gallery roof.

Department of the Navy. FY 1994/FY 1995 Biennial Budget Estimates. Military Construction Program. FY 1994

DTIC Science & Technology

1992-01-01

3 are severely deteriorated. The concrete deck and supporting wood -pile structure are nearing the end of their life cycle. Both piers are to be...PROPOSED CONSTRUCTION One-story building with concrete foundation walls, load bearing masonry walls, and concrete floors; roof with wood truss framing...concrete building addition; concrete foundation and slab on grade; wood truss roof; 750 KVA. 3 phase transformer; utilities; concrete and storm drain. 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.

Residential Photovoltaic/Thermal Energy System

NASA Technical Reports Server (NTRS)

Selcuk, M. K.

1987-01-01

Proposed system supplies house with both heat and electricity. Pair of reports describes concept for self-sufficient heating, cooling, and power-generating system for house. Panels on walls of house provide hot water, space heating, and heat to charge heat-storage system, and generate electricity for circulation pumps and fans. Roof panels generate electricity for household, operate heat pump for summer cooling, and provide supplementary winter heating via heat pump, using solar-cell cooling-fluid loop. Wall and roof panels used independently.

MUNI Ways and Structures Building Integrated Solar Membrane Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Randall

The initial goal of the MUNI Ways and Structures Building Integrated Solar Membrane Installation Project was for the City and County of San Francisco (CCSF) to gain experience using the integrated higher efficiency solar photovoltaic (PV) single-ply membrane product, as it differs from the conventional, low efficiency, thin-film PV products, to determine the feasibility of success of larger deployment. As several of CCSF’s municipal rooftops are constrained with respect to weight restrictions, staff of the Energy Generation Group of the San Francisco Public Utilities Commission (SFPUC) proposed to install a solar PV system using single-ply membrane The installation of themore » 100 kW (DC-STC) lightweight photo voltaic (PV) system at the MUNI Ways and Structures Center (700 Pennsylvania Ave., San Francisco) is a continuation of the commitment of the City and County of San Francisco (CCSF) to increase the pace of municipal solar development, and serve its municipal facilities with clean renewable energy. The fourteen (14) solar photovoltaic systems that have already been installed at CCSF municipal facilities are assisting in the reduction of fossil-fuel use, and reduction of greenhouse gases from fossil combustion. The MUNI Ways & Structures Center roof has a relatively low weight-bearing capacity (3.25 pounds per square foot) and use of traditional crystalline panels was therefore rejected. Consequently it was decided to use the best available highest efficiency Building-Integrated PV (BIPV) technology, with consideration for reliability and experience of the manufacturer which can meet the low weight-bearing capacity criteria. The original goal of the project was to provide an opportunity to monitor the results of the BIPV technology and compare these results to other City and County of San Francisco installed PV systems. The MUNI Ways and Structures Center was acquired from the Cookson Doors Company, which had run the Center for many decades. The building was renovated in 1998, but the existing roof had not been designed to carry a large load. Due to this fact, a complete roofing and structural analysis had to be performed to match the available roof loading to the existing and/or new solar PV technology, and BIPV was considered an excellent solution for this structure with the roof weight limitations. The solar BIPV system on the large roof area was estimated to provide about 25% of the total facility load with an average of 52,560 kWh per month. In order to accomplish the goals of the project, the following steps were performed: 1. SFPUC and consultants evaluated the structural capability of the facility roof, with recommendations for improvements necessary to accommodate the solar PV system and determine the suitable size of the system in kilowatts. The electrical room and switchgear were evaluated for any improvements necessary and to identify any constraints that might impede the installation of necessary inverters, transformers or meters. 2. Development of a design-build Request for Proposal (RFP) to identify the specifications for the solar PV system, and to include SFPUC technical specifications, equipment warranties and performance warranties. Due to potential labor issues in the local solar industry, SFPUC adjusted the terms of the RFP to more clearly define scope of work between electricians, roofers and laborers. 3. Design phase of project included electrical design drawings, calculations and other construction documents to support three submittals: 50% (preliminary design), 90% (detailed design) and 100% (Department of Building Inspection permit approved). 4. Installation of solar photovoltaic panels, completion of conduit and wiring work, connection of inverters, isolation switches, meters and Data Acquisition System by Contractor (Department of Public Works). 5. Commissioning of system, including all necessary tests to make the PV system fully functional and operational at its rated capacity of 100 kW (DC-STC). Following completion of these steps, the solar PV system was installed and fully integrated by late October 2013. The interconnection with PG&E utility grid was completed and the system began generating power on November 21, 2013. The projected annual energy generation for the system is estimated at 127,120 kWh/year.« less

Design automation of load-bearing arched structures of roofs of tall buildings

NASA Astrophysics Data System (ADS)

Kulikov, Vladimir

2018-03-01

The article considers aspects of the possible use of arched roofs in the construction of skyscrapers. Tall buildings experience large load from various environmental factors. Skyscrapers are subject to various and complex types of deformation of its structural elements. The paper discusses issues related to the aerodynamics of various structural elements of tall buildings. The technique of solving systems of equations state method of Simpson. The article describes the optimization of geometric parameters of bearing elements of the arched roofs of skyscrapers.

Building Integrated Photovoltaic (BIPV) Roofs for Sustainability and Energy Efficiency

DTIC Science & Technology

2013-09-10

roofs that utilize a-Si PV modules, like the ones in this study , experienced a significantly lower price reduction, which makes them less cost...facility did not matter, a roof in need of replacement was a better use of the funds. As for Site III, since one of the objectives was to study the...at Site II (NAS Patuxent River) and Site III (MCAS Yuma). Equipment regarding the study of the load on the HVAC system, including measuring the

Department of the Air Force FY 1994 Budget Estimates, Military Construction and Family Housing. Volume 1. Justification Data Submitted to Congress April 1993

DTIC Science & Technology

1993-01-01

concrete floor, masonry walls, roof joists, and roof system. Facility includes dining area, kitchen, serving area, dishwashing area, bakery , regular and...brick exterior, and standing seam metal roof. Facility includes dining area, serving line, kitchen, dishwashing area, bakery , refrigerated and non...desperately needed. Adequate child care is much more difficult to obtain in Europe than in the States since there are no franchised child care centers on the

Residential roof condition assessment system using deep learning

NASA Astrophysics Data System (ADS)

Wang, Fan; Kerekes, John P.; Xu, Zhuoyi; Wang, Yandong

2018-01-01

The emergence of high resolution (HR) and ultra high resolution (UHR) airborne remote sensing imagery is enabling humans to move beyond traditional land cover analysis applications to the detailed characterization of surface objects. A residential roof condition assessment method using techniques from deep learning is presented. The proposed method operates on individual roofs and divides the task into two stages: (1) roof segmentation, followed by (2) condition classification of the segmented roof regions. As the first step in this process, a self-tuning method is proposed to segment the images into small homogeneous areas. The segmentation is initialized with simple linear iterative clustering followed by deep learned feature extraction and region merging, with the optimal result selected by an unsupervised index, Q. After the segmentation, a pretrained residual network is fine-tuned on the augmented roof segments using a proposed k-pixel extension technique for classification. The effectiveness of the proposed algorithm was demonstrated on both HR and UHR imagery collected by EagleView over different study sites. The proposed algorithm has yielded promising results and has outperformed traditional machine learning methods using hand-crafted features.

Thermal and Energy Performance of Conditioned Building Due To Insulated Sloped Roof

NASA Astrophysics Data System (ADS)

Irwan, Suhandi Syiful; Ahmed, Azni Zain; Zakaria, Nor Zaini; Ibrahim, Norhati

2010-07-01

For low-rise buildings in equatorial region, the roof is exposed to solar radiation longer than other parts of the envelope. Roofs are to be designed to reject heat and moderate the thermal impact. These are determined by the design and construction of the roofing system. The pitch of roof and the properties of construction affect the heat gain into the attic and subsequently the indoor temperature of the living spaces underneath. This finally influences the thermal comfort conditions of naturally ventilated buildings and cooling load of conditioned buildings. This study investigated the effect of insulated sloping roof on thermal energy performance of the building. A whole-building thermal energy computer simulation tool, Integrated Environmental Solution (IES), was used for the modelling and analyses. A building model with dimension of 4.0 m × 4.0 m × 3.0 m was designed with insulated roof and conventional construction for other parts of the envelope. A 75 mm conductive insulation material with thermal conductivity (k-value) of 0.034 Wm-1K-1 was installed underneath the roof tiles. The building was modelled with roof pitch angles of 0° , 15°, 30°, 45°, 60° and simulated for the month of August in Malaysian climate conditions. The profile for attic temperature, indoor temperature and cooling load were downloaded and evaluated. The optimum roof pitch angle for best thermal performance and energy saving was identified. The results show the pitch angle of 0° is able to mitigate the thermal impact to provide the best thermal condition with optimum energy savings. The maximum temperature difference between insulated and non-insulted roof for attic (AtticA-B) and indoor condition (IndoorA-B) is +7.8 °C and 0.4 °C respectively with an average energy monthly savings of 3.9 %.

Technical Assistance | State, Local, and Tribal Governments | NREL

Science.gov Websites

contracting, and training and workshops. Photo of a red house with solar panels on the roof and a big yellow Clean Cities Photo of a photovoltaic system on the roof of the Murdough Hall to compliment teaching and

29. Attic interior showing roof truss system over waiting room; ...

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

29. Attic interior showing roof truss system over waiting room; note knob-and-tube wiring system; brick section at far left is rear of tower, which of brick masonry construction above the first story level, joined to the exterior walls of stone masonry; view to southeast along axis of building, 90mm lens and electronic flash illumination. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

Hurricane Matthew Damage Survey

NASA Image and Video Library

2016-10-08

The roof of the Operations Support Building I is seen during an aerial survey of NASA's Kennedy Space Center in Florida on Saturday. The survey was performed to identify structures and facilities that may have sustained damage from Hurricane Matthew as the storm passed to the east of Kennedy on Oct. 6 and 7, 2016. Officials determined that the center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected. NASA closed the center ahead of the storm’s onset and only a small team of specialists known as the Rideout Team was on the center as the storm approached and passed.

Hurricane Matthew Damage Survey

NASA Image and Video Library

2016-10-08

The roof of the Operations Support Building II is seen during an aerial survey of NASA's Kennedy Space Center in Florida on Saturday. The survey was performed to identify structures and facilities that may have sustained damage from Hurricane Matthew as the storm passed to the east of Kennedy on Oct. 6 and 7, 2016. Officials determined that the center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected. NASA closed the center ahead of the storm’s onset and only a small team of specialists known as the Rideout Team was on the center as the storm approached and passed.

[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.

The skull roof tracks the brain during the evolution and development of reptiles including birds.

PubMed

Fabbri, Matteo; Mongiardino Koch, Nicolás; Pritchard, Adam C; Hanson, Michael; Hoffman, Eva; Bever, Gabriel S; Balanoff, Amy M; Morris, Zachary S; Field, Daniel J; Camacho, Jasmin; Rowe, Timothy B; Norell, Mark A; Smith, Roger M; Abzhanov, Arhat; Bhullar, Bhart-Anjan S

2017-10-01

Major transformations in brain size and proportions, such as the enlargement of the brain during the evolution of birds, are accompanied by profound modifications to the skull roof. However, the hypothesis of concerted evolution of shape between brain and skull roof over major phylogenetic transitions, and in particular of an ontogenetic relationship between specific regions of the brain and the skull roof, has never been formally tested. We performed 3D morphometric analyses to examine the deep history of brain and skull-roof morphology in Reptilia, focusing on changes during the well-documented transition from early reptiles through archosauromorphs, including nonavian dinosaurs, to birds. Non-avialan taxa cluster tightly together in morphospace, whereas Archaeopteryx and crown birds occupy a separate region. There is a one-to-one correspondence between the forebrain and frontal bone and the midbrain and parietal bone. Furthermore, the position of the forebrain-midbrain boundary correlates significantly with the position of the frontoparietal suture across the phylogenetic breadth of Reptilia and during the ontogeny of individual taxa. Conservation of position and identity in the skull roof is apparent, and there is no support for previous hypotheses that the avian parietal is a transformed postparietal. The correlation and apparent developmental link between regions of the brain and bony skull elements are likely to be ancestral to Tetrapoda and may be fundamental to all of Osteichthyes, coeval with the origin of the dermatocranium.

Portulaca grandiflora as green roof vegetation: Plant growth and phytoremediation experiments.

PubMed

Vijayaraghavan, K; Arockiaraj, Jesu; Kamala-Kannan, Seralathan

2017-06-03

Finding appropriate rooftop vegetation may improve the quality of runoff from green roofs. Portulaca grandiflora was examined as possible vegetation for green roofs. Green roof substrate was found to have low bulk density (360.7 kg/m 3 ) and high water-holding capacity (49.4%), air-filled porosity (21.1%), and hydraulic conductivity (5270 mm/hour). The optimal substrate also supported the growth of P. grandiflora with biomass multiplication of 450.3% and relative growth rate of 0.038. Phytoextraction potential of P. grandiflora was evaluated using metal-spiked green roof substrate as a function of time and spiked substrate metal concentration. It was identified that P. grandiflora accumulated all metals (Al, Cd, Cr, Cu, Fe, Ni, Pb, and Zn) from metal-spiked green roof substrate. At the end of 40 days, P. grandiflora accumulated 811 ± 26.7, 87.2 ± 3.59, 416 ± 15.8, 459 ± 15.6, 746 ± 20.9, 357 ± 18.5, 565 ± 6.8, and 596 ± 24.4 mg/kg of Al, Cd, Cr, Cu, Fe, Ni, Pb and Zn, respectively. Results also indicated that spiked substrate metal concentration strongly influenced metal accumulation property of P. grandiflora with metal uptake increased and accumulation factor decreased with increase in substrate metal concentration. P. grandiflora also showed potential to translocate all the examined metals with translocation factor greater than 1 for Al, Cu, Fe, and Zn, indicating hyperaccumulation property.

Drought versus heat: What's the major constraint on Mediterranean green roof plants?

PubMed

Savi, Tadeja; Dal Borgo, Anna; Love, Veronica L; Andri, Sergio; Tretiach, Mauro; Nardini, Andrea

2016-10-01

Green roofs are gaining momentum in the arid and semi-arid regions due to their multiple benefits as compared with conventional roofs. One of the most critical steps in green roof installation is the selection of drought and heat tolerant species that can thrive under extreme microclimate conditions. We monitored the water status, growth and survival of 11 drought-adapted shrub species grown on shallow green roof modules (10 and 13cm deep substrate) and analyzed traits enabling plants to cope with drought (symplastic and apoplastic resistance) and heat stress (root membrane stability). The physiological traits conferring efficiency/safety to the water transport system under severe drought influenced plant water status and represent good predictors of both plant water use and growth rates over green roofs. Moreover, our data suggest that high substrate temperature represents a stress factor affecting plant survival to a larger extent than drought per se. In fact, the major cause influencing seedling survival on shallow substrates was the species-specific root resistance to heat, a single and easy measurable trait that should be integrated into the methodological framework for screening and selection of suitable shrub species for roof greening in the Mediterranean. Copyright © 2016 Elsevier B.V. All rights reserved.

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 building by installing green roofs and, thus, providing a conversion of rooftops in pervious areas; the objective is modeling hydrological fluxes (interception, evapotranspiration, soil water fluxes in the surface and hypodermic components) 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). The sensitivity analysis of hydrological processes at different hydrological, climatic and geometric parameters has allowed to draw some general guidelines useful in the design and construction of this type of drainage systems.

A Web-Based Simulation Tool on The Performance of Different Roofing Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

The Roof Savings Calculator (www.roofcalc.com) provides the general public with a web-based program for calculating the energy savings of different roofing and attic systems on four different building types (residential, office, retail, and warehouse) in 239 US TMY2 locations. The core simulation engine of the RSC is doe2attic, which couples the AtticSim program developed by Oak Ridge National Laboratory with the DOE-2.1E program originally developed by Lawrence Berkeley National Laboratory a widely used whole-building simulation program since the 1980 s. Although simulating heat flows through the roof may seem to be an easy task, simulating the net effect of roofingmore » strategies on building heating and cooling energy use can be quite challenging. Few simulation programs can reliably capture dynamics including an attic or plenum with large day-night temperature swings, high ventilation rates, significant radiant exchange between the roof and the attic floor and thermal interactions when there are ducts in the attic, as is typical in North American buildings. The doe2attic program has been tested against detailed measurements gathered in two residential buildings in Fresno, California from cooling energy use to air and surface temperatures, and heat fluxes of the roof and attic floor. The focus of this paper is on the doe2attic simulation tool, but the user interface of the RSC will also be briefly described.« less

Pre-Engineered Buildings and School Construction.

ERIC Educational Resources Information Center

Jurney, Douglas M.

1979-01-01

A preengineered building has the advantages of factory production and computerized quality control. Insulation efficiency and a roofing system that enables the entire roof membrane to react a full two inches to any temperature-induced movement are two of the innovations of preengineered building research. (Author/MLF)

COOL ROOF COATINGS INCORPORATING GLASS HOLLOW MICROSPHERES

EPA Science Inventory

Solar Gain is in part responsible for up to 56% of energy consumed by cooling systems in residential buildings. By reflecting and scattering radiant energy from the sun, the surface temperature of exterior walls and roofs can be greatly reduced. Previous studies have indicated...

5. EXTERIOR OF TRIPLEX COTTAGE ROOF SHOWING MANVILLE COMPOSITION SHINGLES, ...

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

5. EXTERIOR OF TRIPLEX COTTAGE ROOF SHOWING MANVILLE COMPOSITION SHINGLES, POURED CONCRETE CHIMNEYS, AND TRANSLUCENT PLASTIC COVERING OVER WALKWAY AT REAR OF HOUSE (PHOTO LEFT). VIEW TO NORTHWEST. - Lee Vining Creek Hydroelectric System, Triplex Cottage, Lee Vining Creek, Lee Vining, Mono County, CA

Project Overcoat - An Exploration of Exterior Insulation Strategies for 1-1/2-Story Roof Applications in Cold Climates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ojczyk, Cindy; Mosiman, Garrett; Huelman, Pat

The development of an alternative method to interior-applied insulation strategies or exterior applied 'band-aids' such as heat tapes and ice belts may help reduce energy needs of millions of 1-1/2 story homes while reducing the risk of ice dam formation. A potential strategy for energy improvement of the roof is borrowed from new construction best practices: Here an 'overcoat' of a continuous air, moisture, and thermal barrier is applied on the outside of the roof structure for improved overall performance. The continuous insulation of this approach facilitates a reduction in thermal bridging which could further reduce energy consumption and bringmore » existing homes closer to meeting the Building America goals for energy reduction. Research favors an exterior approach to deep energy retrofits and ice dam prevention in existing homes. The greatest amount of research focuses on whole house deep energy retrofits leaving a void in roof-only applications. The research is also void of data supporting the hygrothermal performance, durability, constructability, and cost of roof-only exterior overcoat strategies. Yet, contractors interviewed for this report indicate an understanding that exterior approaches are most promising for mitigating ice dams and energy loss and are able to sell these strategies to homeowners.« less

Photocopy of photograph (original negative located in LBNL Photo Lab ...

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

Photocopy of photograph (original negative located in LBNL Photo Lab Collection). March 2005. CENTRAL SUPPORT COLUMN EXTENDING THROUGH CRANES AND ROOF SUPPORT TRUSS, BEVATRON - University of California Radiation Laboratory, Bevatron, 1 Cyclotron Road, Berkeley, Alameda County, CA

Green roof soil system affected by soil structural changes: A project initiation

NASA Astrophysics Data System (ADS)

Jelínková, Vladimíra; Dohnal, Michal; Šácha, Jan; Šebestová, Jana; Sněhota, Michal

2014-05-01

Anthropogenic soil systems and structures such as green roofs, permeable or grassed pavements comprise appreciable part of the urban watersheds and are considered to be beneficial regarding to numerous aspects (e.g. carbon dioxide cycle, microclimate, reducing solar absorbance and storm water). Expected performance of these systems is significantly affected by water and heat regimes that are primarily defined by technology and materials used for system construction, local climate condition, amount of precipitation, the orientation and type of the vegetation cover. The benefits and potencies of anthropogenic soil systems could be considerably threatened in case when exposed to structural changes of thin top soil layer in time. Extensive green roof together with experimental green roof segment was established and advanced automated monitoring system of micrometeorological variables was set-up at the experimental site of University Centre for Energy Efficient Buildings as an interdisciplinary research facility of the Czech Technical University in Prague. The key objectives of the project are (i) to characterize hydraulic and thermal properties of soil substrate studied, (ii) to establish seasonal dynamics of water and heat in selected soil systems from continuous monitoring of relevant variables, (iii) to detect structural changes with the use of X-ray Computed Tomography, (iv) to identify with the help of numerical modeling and acquired datasets how water and heat dynamics in anthropogenic soil systems are affected by soil structural changes. Achievements of the objectives will advance understanding of the anthropogenic soil systems behavior in conurbations with the temperate climate.

Intercondylar roof impingement pressure after anterior cruciate ligament reconstruction in a porcine model.

PubMed

Iriuchishima, Takanori; Tajima, Goro; Ingham, Sheila J M; Shen, Wei; Horaguchi, Takashi; Saito, Akiyoshi; Smolinski, Patrick; Fu, Freddie H

2009-06-01

Anterior cruciate ligament (ACL) graft impingement against the intercondylar roof has been postulated, but not thoroughly investigated. The roof impingement pressure changes with different tibial and femoral tunnel positions in ACL reconstruction. Anterior tibial translation is also affected by the tunnel positions of ACL reconstruction. The study design included a controlled laboratory study. In 15 pig knees, the impingement pressure between ACL and intercondylar roof was measured using pressure sensitive film before and after ACL single bundle reconstruction. ACL reconstructions were performed in each knee with two different tibial and femoral tunnel position combinations: (1) tibial antero-medial (AM) tunnel to femoral AM tunnel (AM to AM) and (2) tibial postero-lateral (PL) tunnel to femoral High-AM tunnel (PL to High-AM). Anterior tibial translation (ATT) was evaluated after each ACL reconstruction using robotic/universal force-moment sensor testing system. Neither the AM to AM nor the PL to High-AM ACL reconstruction groups showed significant difference when compared with intact ACL in roof impingement pressure. The AM to AM group had a significantly higher failure load than PL to High-AM group. This study showed how different tunnel placements affect the ACL-roof impingement pressure and anterior-posterior laxity in ACL reconstruction. Anatomical ACL reconstruction does not cause roof impingement and it has a biomechanical advantage in ATT when compared with non-anatomical ACL reconstructions in the pig knee. There is no intercondylar roof impingement after anatomical single bundle ACL reconstruction.

Insulation Retrofit under Low-Slope Roofs.

DTIC Science & Technology

1982-02-01

Johns-Manville "Money-Clip" System 13 7 Completed "Money-Clip" Installation 14 4 8 Owens - Corning Fiberglas "Energy Miser" System 14 9 Deteriorated...lip" installationi. Figure 8. Owens - Corning Fiberglas "Energy Miser" systemn. (From The If.nvrgv,%Mise~r Sr1stenz [Owens Corningl .) 14 Figure 9...evaluating the products and systems available for upgrading the thermal prop- Johns-Manville and Owens - Corning Fiberglas each erties of low-slope roofs by

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.

New technologies of mining stratal minerals and their computation

NASA Astrophysics Data System (ADS)

Beysembayev, K. M.; Reshetnikova, O. S.; Nokina, Z. N.; Teliman, I. V.; Asmagambet, D. K.

2018-03-01

The paper considers the systems of flat and volumetric modeling of controlling long-wall faces for schemes with rock collapse of the immediate and main roof and smooth lowering of the remaining layers, as well as in forming a vault over the face. Stress distributions are obtained for the reference pressure zone. They are needed for recognizing the active state of the long-wall face in the feedback mode. The project of the system “support - lateral rocks” is represented by a multidimensional network base. Its connections reflect the elements of the system or rocks, workings, supports with nodes and parts. The connections reflect the logic of the operation of machines, assemblies and parts, and the types of their mechanical connections. At the nodes of the base, there are built-in systems of object-oriented programming languages. This allows combining spatial elements of the system into a simple neural network.

Evaluation of the Kloswall longwall mining system

NASA Astrophysics Data System (ADS)

Guay, P. J.

1982-04-01

A new longwal mining system specifically designed to extract a very deep web (48 inches or deeper) from a longwall panel was studied. Productivity and cost analysis comparing the new mining system with a conventional longwall operation taking a 30 inch wide web is presented. It is shown that the new system will increase annual production and return on investment in most cases. Conceptual drawings and specifications for a high capacity three drum shearer and a unique shield type of roof support specifically designed for very wide web operation are reported. The advantages and problems associated with wide web mining in general and as they relate specifically to the equipment selected for the new mining system are discussed.

Defeating the Drips.

ERIC Educational Resources Information Center

Moss, Lincoln

2000-01-01

Discusses a holistic approach to preventing moisture penetration of exterior walls in modular school buildings. The problem of roof leaks in modular structures is examined as are approaches to water management, roof waterproofing, the problem of condensation, and the design of heating, ventilation, and air conditioning systems as it affects water…

Apparatus for mounting photovoltaic power generating systems on buildings

DOEpatents

Russell, Miles C [Lincoln, MA

2009-08-18

Rectangular photovoltaic (PV) modules are mounted on a building roof by mounting stands that are distributed in rows and columns. Each stand comprises a base plate and first and second different height brackets attached to opposite ends of the base plate. Each first and second bracket comprises two module-support members. One end of each module is pivotally attached to and supported by a first module-support member of a first bracket and a second module-support member of another first bracket. At its other end each module rests on but is connected by flexible tethers to module-support members of two different second brackets. The tethers are sized to allow the modules to pivot up away from the module-support members on which they rest to a substantially horizontal position in response to wind uplift forces.

The roof plate boundary is a bi-directional organiser of dorsal neural tube and choroid plexus development

PubMed Central

Broom, Emma R.; Gilthorpe, Jonathan D.; Butts, Thomas; Campo-Paysaa, Florent; Wingate, Richard J. T.

2012-01-01

The roof plate is a signalling centre positioned at the dorsal midline of the central nervous system and generates dorsalising morphogenic signals along the length of the neuraxis. Within cranial ventricles, the roof plate gives rise to choroid plexus, which regulates the internal environment of the developing and adult brain and spinal cord via the secretion of cerebrospinal fluid. Using the fourth ventricle as our model, we show that the organiser properties of the roof plate are determined by its boundaries with the adjacent neuroepithelium. Through a combination of in ovo transplantation, co-culture and electroporation techniques in chick embryos between embryonic days 3 and 6, we demonstrate that organiser properties are maintained by interactions between the non-neural roof plate and the neural rhombic lip. At the molecular level, this interaction is mediated by Delta-Notch signalling and upregulation of the chick homologue of Hes1: chairy2. Gain- and loss-of-function approaches reveal that cdelta1 is both necessary and sufficient for organiser function. Our results also demonstrate that while chairy2 is specifically required for the maintenance of the organiser, its ectopic expression is not sufficient to recapitulate organiser properties. Expression of atonal1 in the rhombic lip adjacent at the roof plate boundary is acutely dependent on both boundary cell interactions and Delta-Notch signalling. Correspondingly, the roof plate boundary organiser also signals to the roof plate itself to specify the expression of early choroid plexus markers. Thus, the roof plate boundary organiser signals bi-directionally to acutely coordinate the development of adjacent neural and non-neural tissues. PMID:23052907

The roof plate boundary is a bi-directional organiser of dorsal neural tube and choroid plexus development.

PubMed

Broom, Emma R; Gilthorpe, Jonathan D; Butts, Thomas; Campo-Paysaa, Florent; Wingate, Richard J T

2012-11-01

The roof plate is a signalling centre positioned at the dorsal midline of the central nervous system and generates dorsalising morphogenic signals along the length of the neuraxis. Within cranial ventricles, the roof plate gives rise to choroid plexus, which regulates the internal environment of the developing and adult brain and spinal cord via the secretion of cerebrospinal fluid. Using the fourth ventricle as our model, we show that the organiser properties of the roof plate are determined by its boundaries with the adjacent neuroepithelium. Through a combination of in ovo transplantation, co-culture and electroporation techniques in chick embryos between embryonic days 3 and 6, we demonstrate that organiser properties are maintained by interactions between the non-neural roof plate and the neural rhombic lip. At the molecular level, this interaction is mediated by Delta-Notch signalling and upregulation of the chick homologue of Hes1: chairy2. Gain- and loss-of-function approaches reveal that cdelta1 is both necessary and sufficient for organiser function. Our results also demonstrate that while chairy2 is specifically required for the maintenance of the organiser, its ectopic expression is not sufficient to recapitulate organiser properties. Expression of atonal1 in the rhombic lip adjacent at the roof plate boundary is acutely dependent on both boundary cell interactions and Delta-Notch signalling. Correspondingly, the roof plate boundary organiser also signals to the roof plate itself to specify the expression of early choroid plexus markers. Thus, the roof plate boundary organiser signals bi-directionally to acutely coordinate the development of adjacent neural and non-neural tissues.

Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining

PubMed Central

Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

2018-01-01

Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of “cantilever beam and elastic foundation beam” was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the propagation direction will be roughly along the central line between the initial broken point and the support position. Otherwise, the roof strata will bend with the support shields moving forward, then the fracture angle will be close to the initiation angle and the fault surface will be stepped. PMID:29513703

Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining.

PubMed

Yang, Jing-Hu; Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

2018-01-01

Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of "cantilever beam and elastic foundation beam" was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the propagation direction will be roughly along the central line between the initial broken point and the support position. Otherwise, the roof strata will bend with the support shields moving forward, then the fracture angle will be close to the initiation angle and the fault surface will be stepped.

Bioretention storm water control measures decrease the toxicity of copper roof runoff.

PubMed

LaBarre, William J; Ownby, David R; Rader, Kevin J; Lev, Steven M; Casey, Ryan E

2017-06-01

The present study evaluated the ability of 2 different bioretention storm water control measures (SCMs), planter boxes and swales, to decrease the toxicity of sheet copper (Cu) roofing runoff to Daphnia magna. The present study quantified changes in storm water chemistry as it passed through the bioretention systems and utilized the biotic ligand model (BLM) to assess whether the observed D. magna toxicity could be predicted by variations found in water chemistry. Laboratory toxicity tests were performed using select storm samples with D. magna cultured under low ionic strength conditions that were appropriate for the low ionic strength of the storm water samples being tested. The SCMs decreased toxicity of Cu roof runoff in both the BLM results and the storm water bioassays. Water exiting the SCMs was substantially higher than influent runoff in pH, ions, alkalinity, and dissolved organic carbon and substantially lower in total and dissolved Cu. Daphnids experienced complete mortality in untreated runoff from the Cu roof (the SCM influent); however, for planter and swale effluents, survival averaged 86% and 95%, respectively. The present study demonstrated that conventional bioretention practices, including planter boxes and swales, are capable of decreasing the risk of adverse effects from sheet Cu roof runoff to receiving systems, even before considering dilution of effluents in those receiving systems and associated further reductions in copper bioavailability. Environ Toxicol Chem 2017;36:1680-1688. © 2016 SETAC. © 2016 SETAC.

Particle size distribution variance in untreated urban runoff and its implication on treatment selection.

PubMed

Charters, Frances J; Cochrane, Thomas A; O'Sullivan, Aisling D

2015-11-15

Understanding the particle size distribution (PSD) of sediment in urban runoff assists in the selection of appropriate treatment systems for sediment removal as systems vary in their ability to remove sediment across different particle size fractions. Variation in PSD in runoff from individual urban surfaces both during and across multiple rain events is not well understood and it may lead to performance uncertainty in treatment systems. Runoff PSDs in international literature were compiled to provide a comparative summary of PSDs from different urban surfaces. To further assess both intra-event and inter-event PSD variation, untreated runoff was collected from road, concrete roof, copper roof, and galvanized roof surfaces within an urban catchment exposed to the same rainfall conditions and analysed for PSD and total suspended solids (TSS). Road runoff had the highest TSS concentrations, while copper roofs had high initial TSS that reduced to very low levels under steady state conditions. Despite variation in TSS concentrations, the median particle diameter of the TSS was comparable across the surfaces. Intra-event variation was generally not significant, but substantial inter-event variation was observed, particularly for coarser road and concrete roof surfaces. PSD variation for each surface contributed to a wide range in predicted treatment performance and suggests that short-retention treatment devices carry a high performance risk of not being able to achieve adequate TSS removal across all rain events. Copyright © 2015 Elsevier Ltd. All rights reserved.

Casualties Produced by Impact and Related Topics of People Survivability in a Direct Effects Environment

DTIC Science & Technology

1974-08-01

COPY Reinforced concrete members ( beams and columns ): sizes, spans, support conditions, reinforcement ratios Steel members (open web joists, beams ...order of 30 to 50 percent of gross wall area are expected in upper portions butnt i n areas ’housing EOC’s. Open web joists and precast concrete units...are expected to dominate roof systems. Floors over the EOC’s are expected to be of rein- forced concrete . Cast-in-place flat plates and precast

Handbook for Repairing Nonconventional Roofing Systems

DTIC Science & Technology

1988-12-01

membrane. 61 PIMB (solvent) Figure 71. Apply welding solvent to the PIB patch. Figure 72. Work the solvent Into the P113 patch. Pila 62 (solvent) Figure 73...when exposed to flame but will not burn nor support combustion . PVC repair techniques are basically the same as for a new application of a PVC fully...granules (if desired) before the final coat dries. 83 PUF F4gue 102. Remove the damaged material and bevel the s! des of the hole. 4󈧵, Figure 103. Trim th

Center for Coal-Derived Low Energy Materials for Sustainable Construction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jewell, Robert; Robl, Tom; Rathbone, Robert

2012-06-30

The overarching goal of this project was to create a sustained center to support the continued development of new products and industries that manufacture construction materials from coal combustion by-products or CCB’s (e.g., cements, grouts, wallboard, masonry block, fillers, roofing materials, etc). Specific objectives includes the development of a research kiln and associated system and the formulation and production of high performance low-energy, low-CO2 emitting calcium sulfoaluminate (CAS) cement that utilize coal combustion byproducts as raw materials.

Radiation Control Coatings Installed on Federal Buildings at Tyndall Air Force Base

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaba, R.L.; Petrie, T.W.

1999-03-16

The technical objectives of this CRADA comprise technology deployment and energy conservation efforts with the radiation control coatings industry and the utility sector. The results of this collaboration include a high-level data reporting, analysis and management system to support the deployment efforts. The technical objectives include successfully install, commission, operate, maintain and document the performance of radiation control coatings on roofs at Tyndall AFB and the Buildings Technology Center at the Oak Ridge National Laboratory; determine the life cycle savings that can be achieved by using radiation control coatings on entire roofs at Tyndall AFB, based on documented installed costmore » and operating maintenance costs with and without the coatings; determine if any specific improvements are required in the coatings before they can be successfully deployed in the federal sector; determine the most effective way to facilitate the widespread and rapid deployment of radiation control coatings in the federal sector; and clearly define any barriers to deployment.« less

Rainwater collection and management from roofs at the Edison Environmental Center

EPA Science Inventory

In the past, the EPA’s Edison Environmental Center, a 200 acre federal run facility, directed all rainwater from roofed areas to the existing stormwater conveyance system. Over the last several years, modifications have been made to the practice of discharging stormwater to the e...

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…

Roofing: Workbook and Tests. First-Aid Training.

ERIC Educational Resources Information Center

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

This workbook on first aid is one of a series of nine individual units of instruction for roofing apprenticeship classes in California. The workbook covers 12 topics: introduction to first-aid practices; burns; skeletal injuries; spinal injuries; wounds, bleeding, and bruises; emergencies of the heart and blood circulation system; breathing and…

9. Interior, original Boiler and Engine Room, Engine Stores Building, ...

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

9. Interior, original Boiler and Engine Room, Engine Stores Building, Southern Pacific Railroad Carlin Shops, view to south (90mm lens). Note the roof truss system and built-up iron longitudinal roof girders. - Southern Pacific Railroad, Carlin Shops, Engine Stores Building, Foot of Sixth Street, Carlin, Elko County, NV

13. VIEW LOOKING NORTHEAST FROM ROOF OF WEST BOILER ROOM ...

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

13. VIEW LOOKING NORTHEAST FROM ROOF OF WEST BOILER ROOM AT SIROCCO DUST COLLECTOR WHICH FORMED PART OF THE ORIGINAL POLLUTION CONTROL SYSTEM FOR BOILERS 900 AND 901 INSTALLED IN 1926-1928. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

Water quantity and quality response of a green roof to storm events: Experimental and monitoring observations.

PubMed

Carpenter, Corey M G; Todorov, Dimitar; Driscoll, Charles T; Montesdeoca, Mario

2016-11-01

Syracuse, New York is working under a court-ordered agreement to limit combined sewer overflows (CSO) to local surface waters. Green infrastructure technologies, including green roofs, are being implemented as part of a CSO abatement strategy and to develop co-benefits of diminished stormwater runoff, including decreased loading of contaminants to the wastewater system and surface waters. The objective of this study was to examine the quantity and quality of discharge associated with precipitation events over an annual cycle from a green roof in Syracuse, NY and to compare measurements from this monitoring program with results from a roof irrigation experiment. Wet deposition, roof drainage, and water quality were measured for 87 storm events during an approximately 12 month period over 2011-2012. Water and nutrient (total phosphorus, total nitrogen, and dissolved organic carbon) mass balances were conducted on an event basis to evaluate retention annually and during the growing and non-growing seasons. These results are compared with a hydrological manipulation experiment, which comprised of artificially watering of the roof. Loadings of nutrients were calculated for experimental and actual storms using the concentration of nutrients and the flow data of water discharging the roof. The green roof was effective in retaining precipitation quantity from storm events (mean percent retention 96.8%, SD = 2.7%, n = 87), although the relative fraction of water retained decreased with increases in the size of the event. There was no difference in water retention of the green roof for the growing and non-growing seasons. Drainage waters exhibited high concentration of nutrients during the warm temperature growing season, particularly total nitrogen and dissolved organic carbon. Overall, nutrient losses were low because of the strong retention of water. However, there was marked variation in the retention of nutrients by season due to variations in concentrations in roof runoff. Copyright © 2016 Elsevier Ltd. All rights reserved.

Wind-driven roof turbines: a novel way to improve ventilation for TB infection control in health facilities.

PubMed

Cox, Helen; Escombe, Rod; McDermid, Cheryl; Mtshemla, Yolanda; Spelman, Tim; Azevedo, Virginia; London, Leslie

2012-01-01

Tuberculosis transmission in healthcare facilities contributes significantly to the TB epidemic, particularly in high HIV settings. Although improving ventilation may reduce transmission, there is a lack of evidence to support low-cost practical interventions. We assessed the efficacy of wind-driven roof turbines to achieve recommended ventilation rates, compared to current recommended practices for natural ventilation (opening windows), in primary care clinic rooms in Khayelitsha, South Africa. Room ventilation was assessed (CO₂ gas tracer technique) in 4 rooms where roof turbines and air-intake grates were installed, across three scenarios: turbine, grate and window closed, only window open, and only turbine and grate open, with concurrent wind speed measurement. 332 measurements were conducted over 24 months. For all 4 rooms combined, median air changes per hour (ACH) increased with wind speed quartiles across all scenarios. Higher median ACH were recorded with open roof turbines and grates, compared to open windows across all wind speed quartiles. Ventilation with open turbine and grate exceeded WHO-recommended levels (60 Litres/second/patient) for 95% or more of measurements in 3 of the 4 rooms; 47% in the remaining room, where wind speeds were lower and a smaller diameter turbine was installed. High room ventilation rates, meeting recommended thresholds, may be achieved using wind-driven roof turbines and grates, even at low wind speeds. Roof turbines and air-intake grates are not easily closed by staff, allowing continued ventilation through colder periods. This simple, low-cost technology represents an important addition to our tools for TB infection control.

Wind-Driven Roof Turbines: A Novel Way to Improve Ventilation for TB Infection Control in Health Facilities

PubMed Central

Cox, Helen; Escombe, Rod; McDermid, Cheryl; Mtshemla, Yolanda; Spelman, Tim; Azevedo, Virginia; London, Leslie

2012-01-01

Objective Tuberculosis transmission in healthcare facilities contributes significantly to the TB epidemic, particularly in high HIV settings. Although improving ventilation may reduce transmission, there is a lack of evidence to support low-cost practical interventions. We assessed the efficacy of wind-driven roof turbines to achieve recommended ventilation rates, compared to current recommended practices for natural ventilation (opening windows), in primary care clinic rooms in Khayelitsha, South Africa. Methods Room ventilation was assessed (CO2 gas tracer technique) in 4 rooms where roof turbines and air-intake grates were installed, across three scenarios: turbine, grate and window closed, only window open, and only turbine and grate open, with concurrent wind speed measurement. 332 measurements were conducted over 24 months. Findings For all 4 rooms combined, median air changes per hour (ACH) increased with wind speed quartiles across all scenarios. Higher median ACH were recorded with open roof turbines and grates, compared to open windows across all wind speed quartiles. Ventilation with open turbine and grate exceeded WHO-recommended levels (60 Litres/second/patient) for 95% or more of measurements in 3 of the 4 rooms; 47% in the remaining room, where wind speeds were lower and a smaller diameter turbine was installed. Conclusion High room ventilation rates, meeting recommended thresholds, may be achieved using wind-driven roof turbines and grates, even at low wind speeds. Roof turbines and air-intake grates are not easily closed by staff, allowing continued ventilation through colder periods. This simple, low-cost technology represents an important addition to our tools for TB infection control. PMID:22253742

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.

Temporal variations in the potential hydrological performance of extensive green roof systems

NASA Astrophysics Data System (ADS)

De-Ville, Simon; Menon, Manoj; Stovin, Virginia

2018-03-01

Existing literature provides contradictory information about variation in potential green roof hydrological performance over time. This study has evaluated a long-term hydrological monitoring record from a series of extensive green roof test beds to identify long-term evolutions and sub-annual (seasonal) variations in potential hydrological performance. Monitoring of nine differently-configured extensive green roof test beds took place over a period of 6 years in Sheffield, UK. Long-term evolutions and sub-annual trends in maximum potential retention performance were identified through physical monitoring of substrate field capacity over time. An independent evaluation of temporal variations in detention performance was undertaken through the fitting of reservoir-routing model parameters. Aggregation of the resulting retention and detention variations permitted the prediction of extensive green roof hydrological performance in response to a 1-in-30-year 1-h summer design storm for Sheffield, UK, which facilitated the comparison of multi and sub-annual hydrological performance variations. Sub-annual (seasonal) variation was found to be significantly greater than long-term evolution. Potential retention performance increased by up to 12% after 5-years, whilst the maximum sub-annual variation in potential retention was 27%. For vegetated roof configurations, a 4% long-term improvement was observed for detention performance, compared to a maximum 63% sub-annual variation. Consistent long-term reductions in detention performance were observed in unvegetated roof configurations, with a non-standard expanded-clay substrate experiencing a 45% reduction in peak attenuation over 5-years. Conventional roof configurations exhibit stable long-term hydrological performance, but are nonetheless subject to sub-annual variation.

Photocopy of photograph (digital image maintained in LBNL Photo Lab ...

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

Photocopy of photograph (digital image maintained in LBNL Photo Lab Collection, XBD200503-00117-176). March 2005. CENTRAL COLUMN SUPPORT TO ROOF SHOWING CRANES CENTER SUPPORT TRACK, BEVATRON - University of California Radiation Laboratory, Bevatron, 1 Cyclotron Road, Berkeley, Alameda County, CA

6. Oblique view from liftbed truck, showing northwest and southwest ...

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

6. Oblique view from lift-bed truck, showing northwest and southwest facades; projecting hip roof section supported by masonry pillars marks location of former porte cochere, removed in 1937; that portion wall beneath this roof section, containing visible double doors, is of frame and stucco construction, scored and tinted to imitate sandstone masonry; interior space formed by this enclosure of portion of former porte cochere now contains restrooms; view to southeast, 65mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., roof bolts should be installed on at least 5-foot centers where the work is performed. (2) Where the... opening before any other work or travel in the intersection. (f) ATRS systems in working sections where... panel in advance of the frontal abutment stresses of the panel being mined. (2) When a ground failure...

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., roof bolts should be installed on at least 5-foot centers where the work is performed. (2) Where the... opening before any other work or travel in the intersection. (f) ATRS systems in working sections where... panel in advance of the frontal abutment stresses of the panel being mined. (2) When a ground failure...

40 CFR Table 5 to Subpart Ggg of... - Control Requirements for Items of Equipment That Meet the Criteria of § 63.1252(f)

Code of Federal Regulations, 2010 CFR

2010-07-01

...(h)(2); or (b) Equip with a floating roof that meets the equipment specifications of § 60.693(a)(1)(i... and other points of access to a conveyance system. c A fixed roof may have openings necessary for...

40 CFR 63.653 - Monitoring, recordkeeping, and implementation plan for emissions averaging.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) For each emission point included in an emissions average, the owner or operator shall perform testing, monitoring, recordkeeping, and reporting equivalent to that required for Group 1 emission points complying... internal floating roof, external roof, or a closed vent system with a control device, as appropriate to the...

40 CFR 60.272 - Standard for particulate matter.

Code of Federal Regulations, 2010 CFR

2010-07-01

... may occur during charging periods. (ii) Shop opacity less than 40 percent may occur during tapping... system is operated such that the roof of the shop is closed during the charge and the tap, and emissions to the atmosphere are prevented until the roof is opened after completion of the charge or tap, the...

10. Interior detail, original Boiler and Engine Room, Engine Stores ...

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

10. Interior detail, original Boiler and Engine Room, Engine Stores Building, Southern Pacific Railroad Carlin Shops, view to east (90mm lens). Note the pin-connected roof truss system and built-up iron longitudinal roof girders. - Southern Pacific Railroad, Carlin Shops, Engine Stores Building, Foot of Sixth Street, Carlin, Elko County, NV

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

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. Copyright © 2014 Elsevier B.V. All rights reserved.

Assessment of addition of biochar to filtering mixtures for potential water pollutant removal.

PubMed

Piscitelli, Lea; Rivier, Pierre-Adrien; Mondelli, Donato; Miano, Teodoro; Joner, Erik J

2018-01-01

Green roofs are used increasingly to alleviate peaks of water discharge into the sewage systems in urban areas. Surface runoff from roofs contain pollutants from dry and wet deposition, and green roofs offer a possibility to reduce the amounts of pollutants in the water discharged from roofs by degradation and filtering. These pollutants would otherwise enter wastewater treatments plants and ultimately end up in sewage sludge that is spread on agricultural soils. The most common substrates used in green roofs have limited capacity for filtration and sorption. Also, more sustainable alternatives are sought, due to the high carbon footprint of these materials. Biochar is a carbon-rich material produced by pyrolysis of biomass, and several types of biochar have been described as good sorbents and filter materials. Biochar is also a light and carbon negative material, which may fulfill other desired criteria for new green roof substrates. We here report on an experiment where two types of biochar, produced from olive husks at 450 °C or from forest waste at 850 ° C were mixed with volcanic rock or peat, and tested for retention capacity of phenanthrene and six heavy metals in a column experiment with unsaturated gravimetric water flow lasting for 3 weeks. The results suggest that biochar as a component in green roof substrates perform better than traditional materials, concerning retention of the tested pollutants, and that different types of biochar have different properties in this respect.

High-Performance Energy-Efficient Cool Metal Roof Assemblies Utilizing Building Integrated Renewable Solar Energy Technologies for New and Retrofit Building Construction

DTIC Science & Technology

2014-04-01

technology described in this proposal was first commercialized in 2004. It has been installed in 35 states and 5 countries primarily on residential ...temperatures. o Rainwater harvesting systems help reduce demands on potable water systems and help crowded cities manage stormwater drainage problems...of high density polyisocyanurate rigid insulation board installed over the existing roof and between the sub-purlins with the top layer taped to

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.

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 roof ecosystems.

Manipulating soil microbial communities in extensive green roof substrates.

PubMed

Molineux, Chloe J; Connop, Stuart P; Gange, Alan C

2014-09-15

There has been very little investigation into the soil microbial community on green roofs, yet this below ground habitat is vital for ecosystem functioning. Green roofs are often harsh environments that would greatly benefit from having a healthy microbial system, allowing efficient nutrient cycling and a degree of drought tolerance in dry summer months. To test if green roof microbial communities could be manipulated, we added 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. There are complex relationships between depth and type of substrate and the biomass of different microbial groups, with no clear pattern being observed. Following the addition of inoculants, bacterial groups tended to increase in biomass in shallower substrates, whereas fungal biomass change was dependent on depth and type of substrate. Increased fungal biomass was found in shallow plots containing more crushed concrete and deeper plots containing more crushed brick where compost tea (a live mixture of beneficial bacteria) was added, perhaps due to the presence of helper bacteria for arbuscular mycorrhizal fungi (AMF). Often there was not an additive affect of the microbial inoculations but instead an antagonistic interaction between the added AM fungi and the compost tea. This suggests that some species of microbes may not be compatible with others, as competition for limited resources occurs within the various substrates. The overall results suggest that microbial inoculations of green roof habitats are sustainable. They need only be done once for increased biomass to be found in subsequent years, indicating that this is a novel and viable method of enhancing roof community composition. Copyright © 2014 Elsevier B.V. All rights reserved.

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 governing biodiversity-ecosystem functioning relationships in green roof ecosystems. PMID:20300196

Cooling energy savings potential of light-colored roofs for residential and commercial buildings in 11 US metropolitan areas

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

The U.S. Environmental Protection Agency (EPA) sponsored this project to estimate potential energy and monetary savings resulting from the implementation of light-colored roofs on residential and commercial buildings in major U.S. metropolitan areas. Light-colored roofs reflect more sunlight than dark roofs, so they keep buildings cooler and reduce air-conditioning demand. Typically, rooftops in the United States are dark, and thus there is a potential for saving energy and money by changing to reflective roofs. Naturally, the expected savings are higher in southern, sunny, and cloudless climates. In this study, we make quantitative estimates of reduction in peak power demand andmore » annual cooling electricity use that would result from increasing the reflectivity of the roofs. Since light-colored roofs also reflect heat in the winter, the estimates of annual electricity savings are a net value corrected for the increased wintertime energy use. Savings estimates only include direct reduction in building energy use and do not account for the indirect benefit that would also occur from the reduction in ambient temperature, i.e. a reduction in the heat island effect. This analysis is based on simulations of building energy use, using the DOE-2 building energy simulation program. Our methodology starts with specifying 11 prototypical buildings: single-family residential (old and new), office (old and new), retail store (old and new), school (primary and secondary), health (hospital and nursing home), and grocery store. Most prototypes are simulated with two heating systems: gas furnace and heat pumps. We then perform DOE-2 simulations of the prototypical buildings, with light and dark roofs, in a variety of climates and obtain estimates of the energy use for air conditioning and heating.« less

Rockbolt and installer wand

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

1987-04-07

A rockbolt is described for installation in a bore in the roof of an underground excavation to support the roof, the rockbolt comprising: a sleeve insertable into the bore and having an upper and a lower end; at least one port in the sleeve near the upper end; means inside the sleeve near the upper end for engaging a device for supplying hardenable binder material inserted into the sleeve, the engaging means having at least one passage therein communicating with the port to allow binder material to pass from the device through the engaging means and out the port, tomore » encase the sleeve in binder material; means for engaging the sleeve, near the lower end, to the roof face; means for engaging the sleeve near the upper end to the rock surrounding the bore and means for tensioning the rockbolt to compress the rock between the upper and lower ends.« less

The Lifferth Dome for Small Telescopes

NASA Astrophysics Data System (ADS)

Wilson, B. L.; Olsen, C. S.; Iverson, E. P.; Paget, A.; Lifferth, W.; Brown, P. J.; Moody, J. W.

2004-12-01

The Lifferth Dome is a pull-off roof designed for small telescopes and other observational equipment. It was specifically designed for the needs of the ROVOR project. The roof itself is completely removed from the observatory housing walls and cranked off to the side below the optical horizon. This is done using two swing arms on either side of the observatory that work in unison to lift the roof off the structure and rotate down and away into a cleared location. The torque is provided by a threaded rod connected to an electric motor at the back of the building. As the motor rotates, the threads turn through a threaded sleeve connected directly to the support arms. Advantages to this design are no lost horizon, no roller surfaces to keep clean, low power and simple limit switches. Operation is by computer control using by National Instruments LabVIEW via the internet. We present its design and construction.

Validation of Aurora Solar Inc.'s Envision Software Capabilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

As part of the Department of Energy's SunShot Incubator program, Aurora has worked to develop a web-based application that quickly and precisely calculates the solar potential of a building's roof. The Aurora Envision platform utilizes Google StreetView photos as a basis for measuring roof slope and linear measurements of determining the proper inputs into an eventual shade model. The stated accuracy by Aurora Solar to be tested is lengths within 1.5 feet and slope measurements within 5 degrees. The National Renewable Energy Laboratory (NREL), in partnership with Aurora and supported by the U.S. Department of Energy's (DOE) SunShot Technology tomore » Market Incubator program, independently verified the accuracy of Aurora's Envision measurements on 15 unique roofs throughout the Denver, Colorado region. NREL measured 60 measurements: 27 of 28 slope measurements were within the stated accuracy, 32 of 32 distance measurements were within the stated accuracy.« less

Diesel oil pool fire characteristic under natural ventilation conditions in tunnels with roof openings.

PubMed

Wang, Yanfu; Jiang, Juncheng; Zhu, Dezhi

2009-07-15

In order to research the fire characteristic under natural ventilation conditions in tunnels with roof openings, full-scale experiment of tunnel fire is designed and conducted. All the experimental data presented in this paper can be further applied for validation of numerical simulation models and reduced-scale experimental results. The physical model of tunnel with roof openings and the mathematical model of tunnel fire are presented in this paper. The tunnel fire under the same conditions as experiment is simulated using CFD software. From the results, it can be seen that most smoke is discharged directly off the tunnel through roof openings, so roof openings are favorable for exhausting smoke. But along with the decrease of smoke temperatures, some smoke may backflow and mix with the smoke-free layer below, which leads to fall in visibility and is unfavorable for personnel evacuation. So it is necessary to research more efficient ways for improving the smoke removal efficiency, such as early fire detection systems, adequate warning signs and setting tunnel cap.

A quality control system for digital elevation data

NASA Astrophysics Data System (ADS)

Knudsen, Thomas; Kokkendorf, Simon; Flatman, Andrew; Nielsen, Thorbjørn; Rosenkranz, Brigitte; Keller, Kristian

2015-04-01

In connection with the introduction of a new version of the Danish national coverage Digital Elevation Model (DK-DEM), the Danish Geodata Agency has developed a comprehensive quality control (QC) and metadata production (MP) system for LiDAR point cloud data. The architecture of the system reflects its origin in a national mapping organization where raw data deliveries are typically outsourced to external suppliers. It also reflects a design decision of aiming at, whenever conceivable, doing full spatial coverage tests, rather than scattered sample checks. Hence, the QC procedure is split in two phases: A reception phase and an acceptance phase. The primary aim of the reception phase is to do a quick assessment of things that can typically go wrong, and which are relatively simple to check: Data coverage, data density, strip adjustment. If a data delivery passes the reception phase, the QC continues with the acceptance phase, which checks five different aspects of the point cloud data: Vertical accuracy Vertical precision Horizontal accuracy Horizontal precision Point classification correctness The vertical descriptors are comparatively simple to measure: The vertical accuracy is checked by direct comparison with previously surveyed patches. The vertical precision is derived from the observed variance on well defined flat surface patches. These patches are automatically derived from the road centerlines registered in FOT, the official Danish map data base. The horizontal descriptors are less straightforward to measure, since potential reference material for direct comparison is typically expected to be less accurate than the LiDAR data. The solution selected is to compare photogrammetrically derived roof centerlines from FOT with LiDAR derived roof centerlines. These are constructed by taking the 3D Hough transform of a point cloud patch defined by the photogrammetrical roof polygon. The LiDAR derived roof centerline is then the intersection line of the two primary planes of the transformed data. Since the photogrammetrical and the LiDAR derived roof centerline sets are independently derived, a low RMS difference indicates that both data sets are of very high accuracy. The horizontal precision is derived by doing a similar comparison between LiDAR derived roof centerlines in the overlap zone of neighbouring flight strips. Contrary to the vertical and horizontal descriptors, the point classification correctness is neither geometric, nor well defined. In this case we must resolve by introducing a human in the loop and presenting data in a form that is as useful as possible to this human. Hence, the QC system produces maps of suspicious patterns such as Vegetation below buildings Points classified as buildings where no building is registered in the map data base Building polygons from the map data base without any building points Buildings on roads All elements of the QC process is carried out in smaller tiles (typically 1 km × 1 km) and hence trivially parallelizable. Results from the parallel executing processes are collected in a geospatial data base system (PostGIS) and the progress can be analyzed and visualized in a desktop GIS while the processes run. Implementation wise, the system is based on open source components, primarily from the OSGeo stack (GDAL, PostGIS, QGIS, NumPy, SciPy, etc.). The system specific code is also being open sourced. This open source distribution philosophy supports the parallel execution paradigm, since all available hardware can be utilized without any licensing problems. As yet, the system has only been used for QC of the first part of a new Danish elevation model. The experience has, however, been very positive. Especially notable is the utility of doing full spatial coverage tests (rather than scattered sample checks). This means that error detection and error reports are exactly as spatial as the point cloud data they concern. This makes it very easy for both data receiver and data provider, to discuss and reason about the nature and causes of irregularities.

Hurricane Katrina Wind Investigation Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Desjarlais, A. O.

This investigation of roof damage caused by Hurricane Katrina is a joint effort of the Roofing Industry Committee on Weather Issues, Inc. (RICOWI) and the Oak Ridge National Laboratory/U.S. Department of Energy (ORNL/DOE). The Wind Investigation Program (WIP) was initiated in 1996. Hurricane damage that met the criteria of a major windstorm event did not materialize until Hurricanes Charley and Ivan occurred in August 2004. Hurricane Katrina presented a third opportunity for a wind damage investigation in August 29, 2005. The major objectives of the WIP are as follows: (1) to investigate the field performance of roofing assemblies after majormore » wind events; (2) to factually describe roofing assembly performance and modes of failure; and (3) to formally report results of the investigations and damage modes for substantial wind speeds The goal of the WIP is to perform unbiased, detailed investigations by credible personnel from the roofing industry, the insurance industry, and academia. Data from these investigations will, it is hoped, lead to overall improvement in roofing products, systems, roofing application, and durability and a reduction in losses, which may lead to lower overall costs to the public. This report documents the results of an extensive and well-planned investigative effort. The following program changes were implemented as a result of the lessons learned during the Hurricane Charley and Ivan investigations: (1) A logistics team was deployed to damage areas immediately following landfall; (2) Aerial surveillance--imperative to target wind damage areas--was conducted; (3) Investigation teams were in place within 8 days; (4) Teams collected more detailed data; and (5) Teams took improved photographs and completed more detailed photo logs. Participating associations reviewed the results and lessons learned from the previous investigations and many have taken the following actions: (1) Moved forward with recommendations for new installation procedures; (2) Updated and improved application guidelines and manuals from associations and manufacturers; (3) Launched certified product installer programs; and (4) Submitted building code changes to improve product installation. Estimated wind speeds at the damage locations came from simulated hurricane models prepared by Applied Research Associates of Raleigh, North Carolina. A dynamic hurricane wind field model was calibrated to actual wind speeds measured at 12 inland and offshore stations. The maximum estimated peak gust wind speeds in Katrina were in the 120-130 mph range. Hurricane Katrina made landfall near Grand Isle, Louisiana, and traveled almost due north across the city of New Orleans. Hurricane winds hammered the coastline from Houma, Louisiana, to Pensacola, Florida. The severe flooding problems in New Orleans made it almost impossible for the investigating teams to function inside the city. Thus the WIP investigations were all conducted in areas east of the city. The six teams covered the coastal areas from Bay Saint Louis, Mississippi, on the west to Pascagoula, Mississippi, on the east. Six teams involving a total of 25 persons documented damage to both low slope and steep slope roofing systems. The teams collected specific information on each building examined, including type of structure (use or occupancy), wall construction, roof type, roof slope, building dimensions, roof deck, insulation, construction, and method of roof attachment. In addition, the teams noted terrain exposure and the estimated wind speeds at the building site from the Katrina wind speed map. With each team member assigned a specific duty, they described the damage in detail and illustrated important features with numerous color photos. Where possible, the points of damage initiation were identified and damage propagation described. Because the wind speeds in Katrina at landfall, where the investigations took place, were less than code-specified design speeds, one would expect roof damage to be minimal. One team speculated that damage to all roofs in the area they examined was less than 10% when improper installation and deterioration were eliminated as causes. Roofs designed to code and installed according to manufacturers recommendations performed very well.« less

Measuring Thermal Performance of Building Envelopes: Nine Case Studies,

DTIC Science & Technology

1985-03-01

inch P/B = 11.36, present worth factor for an es- of expanded polystyrene insulation) to the build- calating series for a 15-year period ing exterior...inch of The one MCA building roof we measured was a expanded polystyrene at R-3.6 per inch. Where the cathedral system with a sloped built-up roofing

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...

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

KSC-2013-4176

NASA Image and Video Library

2013-11-19

CAPE CANAVERAL, Fla. -- At Launch Pad 39B at NASA’s Kennedy Space Center in Florida, all of the old crawler track panels have been removed from the surface and construction workers are repairing the concrete surface and catacomb roof below. New crawler track panels will be installed. Launch Pad 39B is being refurbished to support NASA’s Space Launch System and other launch vehicles. The Ground Systems Development and Operations, or GSDO, Program office at Kennedy is leading the center’s transformation to safely handle a variety of rockets and spacecraft. For more information about GSDO, visit: http://go.nasa.gov/groundsystems. Photo credit: NASA/Kim Shiflett

KSC-2013-4174

NASA Image and Video Library

2013-11-19

CAPE CANAVERAL, Fla. -- At Launch Pad 39B at NASA’s Kennedy Space Center in Florida, all of the old crawler track panels have been removed from the surface and construction workers are repairing the concrete surface and catacomb roof below. New crawler track panels will be installed. Launch Pad 39B is being refurbished to support NASA’s Space Launch System and other launch vehicles. The Ground Systems Development and Operations, or GSDO, Program office at Kennedy is leading the center’s transformation to safely handle a variety of rockets and spacecraft. For more information about GSDO, visit: http://go.nasa.gov/groundsystems. Photo credit: NASA/Kim Shiflett

KSC-2013-4175

NASA Image and Video Library

2013-11-19

CAPE CANAVERAL, Fla. -- At Launch Pad 39B at NASA’s Kennedy Space Center in Florida, all of the old crawler track panels have been removed from the surface and construction workers are repairing the concrete surface and catacomb roof below. At far left is the recently-constructed pad elevator. Launch Pad 39B is being refurbished to support NASA’s Space Launch System and other launch vehicles. The Ground Systems Development and Operations, or GSDO, Program office at Kennedy is leading the center’s transformation to safely handle a variety of rockets and spacecraft. For more information about GSDO, visit: http://go.nasa.gov/groundsystems. Photo credit: NASA/Kim Shiflett

30 CFR 75.214 - Supplemental support materials, equipment and tools.

Code of Federal Regulations, 2010 CFR

2010-07-01

... tools. 75.214 Section 75.214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75... accessible location on each working section or within four crosscuts of each working section. (b) The...

Commercial/industrial photovoltaic module and array requirement study. Low-cost solar array project engineering area

NASA Technical Reports Server (NTRS)

1981-01-01

Design requirements for photovoltaic modules and arrays used in commercial and industrial applications were identified. Building codes and referenced standards were reviewed for their applicability to commercial and industrial photovoltaic array installation. Four general installation types were identified - integral (replaces roofing), direct (mounted on top of roofing), stand-off (mounted away from roofing), and rack (for flat or low slope roofs, or ground mounted). Each of the generic mounting types can be used in vertical wall mounting systems. This implies eight mounting types exist in the commercial/industrial sector. Installation costs were developed for these mounting types as a function of panel/module size. Cost drivers were identified. Studies were performed to identify optimum module shapes and sizes and operating voltage cost drivers. The general conclusion is that there are no perceived major obstacles to the use of photovoltaic modules in commercial/industrial arrays.

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.

KSC-04pd1902

NASA Image and Video Library

2004-09-22

KENNEDY SPACE CENTER, FLA. - Workers attempt to secure the roof of the Tile Shop in the Thermal Protection System Facility (TPSF) in preparation for Hurricane Jeanne, which is expected to impact Central Florida Sunday. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, lost approximately 35 percent of its roof during Hurricane Frances, which blew across Central Florida Sept. 4. Jeanne is the fourth hurricane in 45 days to make landfall somewhere in the state.

The detection of the coal roof interface by use of high pressure water

NASA Technical Reports Server (NTRS)

1981-01-01

A device whereby water jets can be used to detect the interface between coal and the overlying roof rock is described. Once this identification is made this distance can be measured using instruments such as the autofocus systems recently developed in the photographic industry. Experiments carried out show that the device can discriminate between coal and rock at coal thicknesses up to 8 inches. An autofocus system was examined which indicates accuracies of better than 0.1 inches.

Evaluating convex roof entanglement measures.

PubMed

Tóth, Géza; Moroder, Tobias; Gühne, Otfried

2015-04-24

We show a powerful method to compute entanglement measures based on convex roof constructions. In particular, our method is applicable to measures that, for pure states, can be written as low order polynomials of operator expectation values. We show how to compute the linear entropy of entanglement, the linear entanglement of assistance, and a bound on the dimension of the entanglement for bipartite systems. We discuss how to obtain the convex roof of the three-tangle for three-qubit states. We also show how to calculate the linear entropy of entanglement and the quantum Fisher information based on partial information or device independent information. We demonstrate the usefulness of our method by concrete examples.

Effects of Solar Photovoltaic Panels on Roof Heat Transfer

NASA Technical Reports Server (NTRS)

Dominguez, A.; Klessl, J.; Samady, M.; Luvall, J. C.

2010-01-01

Building Heating, Ventilation and Air Conditioning (HVAC) is a major contributor to urban energy use. In single story buildings with large surface area such as warehouses most of the heat enters through the roof. A rooftop modification that has not been examined experimentally is solar photovoltaic (PV) arrays. In California alone, several GW in residential and commercial rooftop PV are approved or in the planning stages. With the PV solar conversion efficiency ranging from 5-20% and a typical installed PV solar reflectance of 16-27%, 53-79% of the solar energy heats the panel. Most of this heat is then either transferred to the atmosphere or the building underneath. Consequently solar PV has indirect effects on roof heat transfer. The effect of rooftop PV systems on the building roof and indoor energy balance as well as their economic impacts on building HVAC costs have not been investigated. Roof calculator models currently do not account for rooftop modifications such as PV arrays. In this study, we report extensive measurements of a building containing a flush mount and a tilted solar PV array as well as exposed reference roof. Exterior air and surface temperature, wind speed, and solar radiation were measured and thermal infrared (TIR) images of the interior ceiling were taken. We found that in daytime the ceiling surface temperature under the PV arrays was significantly cooler than under the exposed roof. The maximum difference of 2.5 C was observed at around 1800h, close to typical time of peak energy demand. Conversely at night, the ceiling temperature under the PV arrays was warmer, especially for the array mounted flat onto the roof. A one dimensional conductive heat flux model was used to calculate the temperature profile through the roof. The heat flux into the bottom layer was used as an estimate of the heat flux into the building. The mean daytime heat flux (1200-2000 PST) under the exposed roof in the model was 14.0 Watts per square meter larger than under the tilted PV array. The maximum downward heat flux was 18.7 Watts per square meters for the exposed roof and 7.0 Watts per square meters under the tilted PV array, a 63% reduction due to the PV array. This study is unique as the impact of tilted and flush PV arrays could be compared against a typical exposed roof at the same roof for a commercial uninhabited building with exposed ceiling and consisting only of the building envelope. Our results indicate a more comfortable indoor environment in PV covered buildings without HVAC both in hotter and cooler seasons.

Composition and Diversity of Avian Communities Using a New Urban Habitat: Green Roofs

NASA Astrophysics Data System (ADS)

Washburn, Brian E.; Swearingin, Ryan M.; Pullins, Craig K.; Rice, Matthew E.

2016-06-01

Green roofs on buildings are becoming popular and represent a new component of the urban landscape. Public benefits of green roof projects include reduced stormwater runoff, improved air quality, reduced urban heat island effects, and aesthetic values. As part of a city-wide plan, several green roofs have been constructed at Chicago's O'Hare International Airport (ORD). Like some other landscaping features, green roofs on or near an airport might attract wildlife and thus increase the risk of bird-aircraft collisions. During 2007-2011, we conducted a series of studies to evaluate wildlife use of newly constructed green roofs and traditional (gravel) roofs on buildings at ORD. These green roofs were 0.04-1.62 ha in area and consisted of primarily stonecrop species for vegetation. A total of 188 birds were observed using roofs during this research. Of the birds using green roofs, 66, 23, and 4 % were Killdeer, European Starlings, and Mourning Doves, respectively. Killdeer nested on green roofs, whereas the other species perched, foraged, or loafed. Birds used green roofs almost exclusively between May and October. Overall, avian use of the green roofs was minimal and similar to that of buildings with traditional roofs. Although green roofs with other vegetation types might offer forage or cover to birds and thus attract potentially hazardous wildlife, the stonecrop-vegetated green roofs in this study did not increase the risk of bird-aircraft collisions.

Impact of height and shape of building roof on air quality in urban street canyons

NASA Astrophysics Data System (ADS)

Yassin, Mohamed F.

2011-09-01

A building's roof shape and roof height play an important role in determining pollutant concentrations from vehicle emissions and its complex flow patterns within urban street canyons. The impact of the roof shape and height on wind flow and dispersion of gaseous pollutants from vehicle exhaust within urban canyons were investigated numerically using a Computational Fluid Dynamics (CFD) model. Two-dimensional flow and dispersion of gaseous pollutants were analyzed using standard κ- ɛ turbulence model, which was numerically solved based on Reynolds Averaged Navier-Stokes (RANS) equations. The diffusion fields in the urban canyons were examined with three roof heights ( Z H/ H = 0.17, 0.33 and 0.5) and five roof shapes: (1) flat-shaped roof, (2) slanted-shaped roof, (3) downwind wedge-shaped roof, (4) upwind wedge-shaped roof, and (5) trapezoid-shaped roof. The numerical model was validated against the wind tunnels results in order to optimize the turbulence model. The numerical simulations agreed reasonably with the wind tunnel results. The results obtained indicated that the pollutant concentration increased as the roof height decreases. It also decreased with the slanted and trapezoid-shaped roofs but increased with the flat-shaped roof. The pollutant concentration distributions simulated in the present work, indicated that the variability of the roof shapes and roof heights of the buildings are important factors for estimating air quality within urban canyons.

Investigation of the proposed solar-driven moisture phenomenon in asphalt shingle roofs

DOE PAGES

Boudreaux, Philip; Pallin, Simon; Jackson, Roderick

2016-01-19

We report that unvented, sealed or conditioned attics are an energy efficiency measure to reduce the thermal load of the home and decrease the space conditioning energy consumption. This retrofit is usually done by using spray polyurethane foam underneath the roof sheathing and on the gables and soffits of an attic to provide a thermal and air barrier. Unvented attics perform well from this perspective but from a moisture perspective sometimes the unvented attic homes have high interior humidity or moisture damage to the roof. As homes become more air tight and energy efficient, an understanding of the hygrothermal dynamicsmore » of the home become more important. One proposed reason for high unvented attic humidity has been that moisture can come through the asphalt shingle roof system and increase the moisture content of the roof sheathing and attic air. This has been called solar driven moisture. Oak Ridge National Laboratory (ORNL) investigated this proposed phenomenon by examining the physical properties of a roof and the physics required for the phenomenon. Results showed that there are not favorable conditions for solar driven moisture to occur. ORNL also conducted an experimental study on an unvented attic home and compared the humidity below the roof sheathing before and after a vapor impermeable underlayment was installed. There was no statistically significant difference in absolute humidity before and after the vapor barrier was installed. Finally, the outcome of the theoretical and experimental study both suggest that solar driven moisture does not occur in any significant amount.« less

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

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.

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.

Composition and Diversity of Avian Communities Using a New Urban Habitat: Green Roofs.

PubMed

Washburn, Brian E; Swearingin, Ryan M; Pullins, Craig K; Rice, Matthew E

2016-06-01

Green roofs on buildings are becoming popular and represent a new component of the urban landscape. Public benefits of green roof projects include reduced stormwater runoff, improved air quality, reduced urban heat island effects, and aesthetic values. As part of a city-wide plan, several green roofs have been constructed at Chicago's O'Hare International Airport (ORD). Like some other landscaping features, green roofs on or near an airport might attract wildlife and thus increase the risk of bird-aircraft collisions. During 2007-2011, we conducted a series of studies to evaluate wildlife use of newly constructed green roofs and traditional (gravel) roofs on buildings at ORD. These green roofs were 0.04-1.62 ha in area and consisted of primarily stonecrop species for vegetation. A total of 188 birds were observed using roofs during this research. Of the birds using green roofs, 66, 23, and 4 % were Killdeer, European Starlings, and Mourning Doves, respectively. Killdeer nested on green roofs, whereas the other species perched, foraged, or loafed. Birds used green roofs almost exclusively between May and October. Overall, avian use of the green roofs was minimal and similar to that of buildings with traditional roofs. Although green roofs with other vegetation types might offer forage or cover to birds and thus attract potentially hazardous wildlife, the stonecrop-vegetated green roofs in this study did not increase the risk of bird-aircraft collisions.

PERFORMANCE EVALUATION OF A SUSTAINABLE AND ENERGY EFFICIENT RE-ROOFING TECHNOLOGY USING FIELD-TEST DATA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biswas, Kaushik; Miller, William A; Childs, Phillip W

2011-01-01

Three test attics were constructed to evaluate a new sustainable method of re-roofing utilizing photo-voltaic (PV) laminates, metal roofing panels, and PCM heat sink in the Envelope Systems Research Apparatus (ESRA) facility in the ORNL campus. Figure 1 is a picture of the three attic roofs located adjacent to each other. The leftmost roof is the conventional shingle roof, followed by the metal panel roof incorporating the cool-roof coating, and third from left is the roof with the PCM. On the PCM roof, the PV panels are seen as well; they're labelled from left-to-right as panels 5, 6 and 7.more » The metal panel roof consists of three metal panels with the cool-roof coating; in further discussion this is referred to as the infrared reflective (IRR) metal roof. The IRR metal panels reflect the incoming solar radiation and then quickly re-emit the remaining absorbed portion, thereby reducing the solar heat gain of the attic. Surface reflectance of the panels were measured using a Solar Spectrum Reflectometer. In the 0.35-2.0 {mu}m wavelength interval, which accounts for more than 94% of the solar energy, the IRR panels have an average reflectance of 0.303. In the infrared portion of the spectrum, the IRR panel reflectance is 0.633. The PCM roof consists of a layer of macro-encapsulated bio-based PCM at the bottom, followed by a 2-cm thick layer of dense fiberglass insulation with a reflective surface on top, and metal panels with pre-installed PV laminates on top. The PCM has a melting point of 29 C (84.2 F) and total enthalpy between 180 and 190 J/g. The PCM was macro-packaged in between two layers of heavy-duty plastic foil forming arrays of PCM cells. Two air cavities, between PCM cells and above the fiberglass insulation, helped the over-the-deck natural air ventilation. It is anticipated that during summer, this extra ventilation will help in reducing the attic-generated cooling loads. The extra ventilation, in conjunction with the PCM heat sink, are used to minimize thermal stresses due to the PV laminates on sunny days. In PV laminates sunlight is converted into electricity and heat simultaneous. In case of building integrated applications, a relatively high solar absorption of amorphous silicon laminates can be utilized during the winter for solar heating purposes with PCM providing necessary heat storage capacity. However, PV laminates may also generate increased building cooling loads during the summer months. Therefore, in this project, the PCM heat sink was to minimize summer heat gains as well. The PCM-fibreglass-PV assembly and the IRR metal panels are capable of being installed directly on top of existing shingle roofs during re-roofing, precluding the need for recycling or disposal of waste materials. The PV laminates installed on the PCM attic are PVL-144 models from Uni-Solar. Each laminate contains 22 triple junction amorphous silicon solar cells connected in series. The silicon cells are of dimensions 356 mm x 239 mm (14-in. x 9.4-in.). The PVL-144 laminate is encapsulated in durable ETFE (poly-ethylene-co-tetrafluoroethylene) high light-transmissive polymer. Table 1 lists the power, voltage and current ratings of the PVL-144 panel.« less

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 new wood-shingle roofs were significantly higher than those from aged roofs of a previous study. The study demonstrated that roofs could be a serious source of nonpoint water pollution. Since Zn is the most serious water pollutant and wood shingle is the worst of the four roof types, using less compounds and materials associated with Zn along with good care and maintenance of roofs are critical in reducing Zn pollution in roof runoff.

Problems of natural lighting for deepened buildings and underground premises under screen effect of high-rise construction

NASA Astrophysics Data System (ADS)

Larionova, Kira; Stetsky, Sergey

2018-03-01

The main rationale and objective of the submitted research work is to create a quality lighting environment in the premises of deepened buildings and below-ground structures under screen effect of high-rise construction (high-rise buildings). It is noted, that in modern megapolises, a deficiency of vacant urban territories leads to the increased density of urban development with increased amount of high-rise construction and tendency to increase efficiency in the use of underground space. The natural lighting of premises in underground buildings and structures is the most efficient way, but it can be implemented only under use of roof lighting system in the form of roof monitors or skylights. In this case the levels of indoor natural lighting will be affected with serious screening effect of high-rise buildings in surrounding development. Such an situation is not regulated, or even considered by the contemporary building Codes and Regulations on natural lighting of interiors. The authors offered a new formula for a daylight factor calculation with roof lighting system in the described cases. The results of theoretical calculations and experimental studies showed very similar values. This proved the truth of the offered formula and elaborated method of calculation on the basis of an offered hypothesis. It prooves, that it is possible to use some factor and guide points in the daylight factors design under system of side natural lighting in the same design for a system of roof lighting.

Power Generation Potential and Cost of a Roof Top Solar PV System in Kathmandu, Nepal

NASA Astrophysics Data System (ADS)

Sanjel, N.; Zhand, A.

2017-12-01

The paper presents a comparative study of the 3 most used solar PV module technologies in Nepal, which are Si-mono-crystalline, Si-poly-crystalline and Si-amorphous. The aim of the paper is to present and discuss the recorded Global Solar Radiation, received in the Kathmandu valley by three different, Si-mono-crystalline, Si-poly-crystalline and Si-amorphous calibrated solar cell pyranometers and to propose the best-suited solar PV module technology for roof top solar PV systems inside the Kathmandu valley. Data recorded over the course of seven months, thus covering most of the seasonal meteorological conditions determining Kathmandu valley's global solar radiation reception are presented. The results indicate that the Si-amorphous pyranometer captured 1.56% more global solar radiation than the Si-mono-crystalline and 18.4% more than Si-poly-crystalline pyranometer over the course of seven months. Among the three pyranometer technologies the maximum and minimum cell temperature was measured by the Si-mono-crystalline pyranometer. Following the technical data and discussion, an economical analysis, using the versatile software tool PVSYST V5.01is used to calculate the life cycle costs of a 1kW roof top solar PV RAPS system, with battery storage, and a 1kW roof top solar PV grid connected system with no energy storage facility, through simulations, using average recorded global solar radiation data for the KTM valley and investigated market values for each solar PV module and peripheral equipment costs.

Visual feedback system to reduce errors while operating roof bolting machines

PubMed Central

Steiner, Lisa J.; Burgess-Limerick, Robin; Eiter, Brianna; Porter, William; Matty, Tim

2015-01-01

Problem Operators of roof bolting machines in underground coal mines do so in confined spaces and in very close proximity to the moving equipment. Errors in the operation of these machines can have serious consequences, and the design of the equipment interface has a critical role in reducing the probability of such errors. Methods An experiment was conducted to explore coding and directional compatibility on actual roof bolting equipment and to determine the feasibility of a visual feedback system to alert operators of critical movements and to also alert other workers in close proximity to the equipment to the pending movement of the machine. The quantitative results of the study confirmed the potential for both selection errors and direction errors to be made, particularly during training. Results Subjective data confirmed a potential benefit of providing visual feedback of the intended operations and movements of the equipment. Impact This research may influence the design of these and other similar control systems to provide evidence for the use of warning systems to improve operator situational awareness. PMID:23398703

Impact of small-scale storage systems on the photovoltaic penetration potential at the municipal scale

NASA Astrophysics Data System (ADS)

Ramirez Camargo, Luis; Dorner, Wolfgang

2016-04-01

The yearly cumulated technical energy generation potential of grid-connected roof-top photovoltaic power plants is significantly larger than the demand of domestic buildings in sparsely populated municipalities in central Europe. However, an energy balance with cumulated annual values does not deliver the right picture about the actual potential for photovoltaics since these run on a highly variable energy source as solar radiation. The mismatch between the periods of generation and demand creates hard limitations for the deployment of the theoretical energy generation potential of roof-top photovoltaics. The actual penetration of roof-top photovoltaic is restricted by the energy quality requirements of the grid and/or the available storage capacity for the electricity production beyond the coverage of own demands. In this study we evaluate in how far small-scale storage systems can contribute to increment the grid-connected roof-top photovoltaic penetration in domestic buildings at a municipal scale. To accomplish this, we calculate, in a first step, the total technical roof-top photovoltaic energy generation potential of a municipality in a high spatiotemporal resolution using a procedure that relies on geographic information systems. Posteriorly, we constrain the set of potential photovoltaic plants to the ones that would be necessary to cover the total yearly demand of the municipality. We assume that photovoltaic plants with the highest yearly yield are the ones that should be installed. For this sub-set of photovoltaic plants we consider five scenarios: 1) no storage 2) one 7 kWh battery is installed in every building with a roof-top photovoltaic plant 3) one 10 kWh battery is installed in every building with a roof-top photovoltaic plant 4) one 7 kWh battery is installed in every domestic building in the municipality 5) one 10 kWh battery is installed in every domestic building in the municipality. Afterwards we evaluate the energy balance of the municipality using a series of indicators. These indicators include: a) the total photovoltaic installed capacity, b) the total storage installed capacity, c) the output variability, d) the total unfulfilled demand, e) total excess energy, f) total properly supplied energy, g) the loss of power supply probability, h) the amount of hours of supply higher than the highest demand in a year, i) the number of hours, when supply is 1.5. times higher than the highest demand in a year, and j) the additional storage energy capacity and power required to store all excess energy generated by the photovoltaic installations. The comparison of the proposed indicators serves to quantify the contribution that household-sized small-scale storage systems would make to the energy balance of the studied municipality. Increased installed energy storage capacity allows a higher roof-top photovoltaic share and improves energy utilization, variability and reliability indicators. The proposed methodology serves also to determine the amount of storage capacity with the highest positive impact on the local energy balance.

24 CFR 3280.402 - Test procedures for roof trusses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... procedures are required for new truss designs in all three wind zones and for existing truss designs used in... design loads, and actual support points, and does not restrain horizontal movement. When tested singly or in groups of two or more trusses, trusses shall be mounted on supports and positioned as intended to...

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

Code of Federal Regulations, 2010 CFR

2010-07-01

... External floating roof converted into an internal floating roof. The owner or operator who elects to... 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...

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…

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,…

A Decision Model for Selecting Energy Efficient Technologies for Low-Sloping Roof Tops Using Value-Focused Thinking

DTIC Science & Technology

2007-03-01

Solar Reflectance Index (SRI) is the combined value of the reflectance and emittance, or the roof’s ability to reject heat. A white shingle has an...directly into the building structure, such as a roof shingle or a sheet of glazing (US DOE, 2006b). Figure 2.6. An Example of Fixed Position Solar ...18 Solar Thermal Systems

Asset Management: Roof Maintenance and Facility Energy Retrofits

DTIC Science & Technology

2012-03-01

vapor low emission coatings. Floor finishes completed in ceramic stone tile were the most efficient floor coverings. Fixed insulated fiberglass window...been coined Asset Management which utilizes organizational levels of service, business case analysis, and risk analysis to address urgent...Force have left a number of facility systems such as roofs at risk to disrepair due to a lack of maintenance. Under the principles of asset

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 wasmore » 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.« less

Multi-scale monitoring of a remarkable green roof: the Green Wave of Champs-sur-Marne

NASA Astrophysics Data System (ADS)

Stanic, Filip; Versini, Pierre-Antoine; Schertzer, Daniel; Delage, Pierre; Tchiguirinskaia, Ioulia; Cui, Yu-Jun; Baudoin, Genevieve

2017-04-01

The installation of green infrastructures on existing or new roofs has become very popular in recent years (more than 2 km2 of green roofs is implemented each year in France) for many reasons. Among all of the green roofs' advantages, those related to storm water management are often pushed forward, since it has been pointed out that urban runoff peak can be significantly reduced and delayed thanks to the green roofs' retention and detention capabilities. Microclimate can also be affected by decreasing the temperature in the surrounding green area. However, dynamic physical processes involved in green roofs are highly non linear and variable. In order to accurately assess their performances, detailed monitoring experiments are required, both in situ and in the lab, so as to better understand the thermo-hydric behaviour of green roofs and to capture the related spatio-temporal variability at different scales. Based on these considerations, the 1 ha area wavy-form green roof of a section of the Bienvenüe building, called the Green Wave, is currently being monitored in Champs-sur-Marne (France), in front of Ecole des Ponts ParisTech. Initiated in the "Blue Green Dream" European project, detailed measurements systems have been implemented for studying all components of the water balance. Among others, a wireless network of water content and temperature sensors has been especially installed for characterizing spatial and temporal variability of infiltration, retention and evapotranspiration processes. In parallel, some laboratory tests have been conducted to better characterize the hydro-mechanical properties of the substrate. Moreover, at the Green Wave scale, some discharge measurements are carried out in the storm-water pipes that are collecting drained water, to determine runoff flow. This talk will present the current monitoring campaigns and analyze the data collected in the Universal Multifractal framework. This work represents the initial stage for developing a model capable to simulate reliable hydrological responses of different kinds of green roofs. Such a tool could be used to quantify hydrological impacts and interfere with the stormwater policies at the lot scale.

Retention performance of green roofs in representative climates worldwide

NASA Astrophysics Data System (ADS)

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

2017-10-01

The ongoing process of global urbanization contributes to an increase in stormwater runoff from impervious surfaces, threatening also water quality. Green roofs have been proved to be innovative stormwater management measures to partially restore natural states, enhancing interception, infiltration and evapotranspiration fluxes. The amount of water that is retained within green roofs depends not only on their depth, but also on the climate, which drives the stochastic soil moisture dynamic. In this context, a simple tool for assessing performance of green roofs worldwide in terms of retained water is still missing and highly desirable for practical assessments. The aim of this work is to explore retention performance of green roofs as a function of their depth and in different climate regimes. Two soil depths are investigated, one representing the intensive configuration and another representing the extensive one. The role of the climate in driving water retention has been represented by rainfall and potential evapotranspiration dynamics. A simple conceptual weather generator has been implemented and used for stochastic simulation of daily rainfall and potential evapotranspiration. Stochastic forcing is used as an input of a simple conceptual hydrological model for estimating long-term water partitioning between rainfall, runoff and actual evapotranspiration. Coupling the stochastic weather generator with the conceptual hydrological model, we assessed the amount of rainfall diverted into evapotranspiration for different combinations of annual rainfall and potential evapotranspiration in five representative climatic regimes. Results quantified the capabilities of green roofs in retaining rainfall and consequently in reducing discharges into sewer systems at an annual time scale. The role of substrate depth has been recognized to be crucial in determining green roofs retention performance, which in general increase from extensive to intensive settings. Looking at the 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.

Spatially dependent biotic and abiotic factors drive survivorship and physical structure of green roof vegetation.

PubMed

Aloisio, Jason M; Palmer, Matthew I; Giampieri, Mario A; Tuininga, Amy R; Lewis, James D

2017-01-01

Plant survivorship depends on biotic and abiotic factors that vary at local and regional scales. This survivorship, in turn, has cascading effects on community composition and the physical structure of vegetation. Survivorship of native plant species is variable among populations planted in environmentally stressful habitats like urban roofs, but the degree to which factors at different spatial scales affect survivorship in urban systems is not well understood. We evaluated the effects of biotic and abiotic factors on survivorship, composition, and physical structure of two native perennial species assemblages, one characterized by a mixture of C 4 grasses and forbs (Hempstead Plains, HP) and one characterized by a mixture of C 3 grasses and forbs (Rocky Summit, RS), that were initially sown at equal ratios of growth forms (5:1:4; grass, N-fixing forb and non-N-fixing forb) in replicate 2-m 2 plots planted on 10 roofs in New York City (New York, USA). Of 24 000 installed plants, 40% survived 23 months after planting. Within-roof factors explained 71% of variation in survivorship, with biotic (species identity and assemblage) factors accounting for 54% of the overall variation, and abiotic (growing medium depth and plot location) factors explaining 17% of the variation. Among-roof factors explained 29% of variation in survivorship and increased solar radiation correlated with decreased survivorship. While growing medium properties (pH, nutrients, metals) differed among roofs there was no correlation with survivorship. Percent cover and sward height increased with increasing survivorship. At low survivorship, cover of the HP assemblage was greater compared to the RS assemblage. Sward height of the HP assemblage was about two times greater compared to the RS assemblage. These results highlight the effects of local biotic and regional abiotic drivers on community composition and physical structure of green roof vegetation. As a result, initial green roof plant composition and roof microclimate may have long-term effects on community dynamics, ecosystem function, and urban biodiversity. © 2016 by the Ecological Society of America.

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.

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. Copyright © 2014 Elsevier B.V. All rights reserved.

Deployable Temporary Shelter

NASA Technical Reports Server (NTRS)

Shaffer, Joe R.; Headley, David E.

1993-01-01

Compact storable components expand to create large shelter. Fully deployed structure provides large, unobstructed bay. Deployed trusses support wall and roof blankets. Provides temporary cover for vehicles, people, and materials. Terrestrial version used as garage, hangar, or large tent.

49 CFR 238.123 - Emergency roof access.

Code of Federal Regulations, 2010 CFR

2010-10-01

... be free of any rigid secondary structure (e.g., a diffuser or diffuser support, lighting back fixture... a hatch, it shall be possible to push interior panels or liners out of their retention devices and...

Technology Solutions Case Study: Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1-1/2 Story Homes in Cold Climates, Minneapolis, MN

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

This case study describes the External Thermal and Moisture Management System developed by the NorthernSTAR Building America Partnership. This system is typically used in deep energy retrofits and is a valuable approach for the roof-only portions of existing homes, particularly the 1 1/2-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

Citywide Impacts of Cool Roof and Rooftop Solar Photovoltaic Deployment on Near-Surface Air Temperature and Cooling Energy Demand

NASA Astrophysics Data System (ADS)

Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Martilli, A.

2016-10-01

Assessment of mitigation strategies that combat global warming, urban heat islands (UHIs), and urban energy demand can be crucial for urban planners and energy providers, especially for hot, semi-arid urban environments where summertime cooling demands are excessive. Within this context, summertime regional impacts of cool roof and rooftop solar photovoltaic deployment on near-surface air temperature and cooling energy demand are examined for the two major USA cities of Arizona: Phoenix and Tucson. A detailed physics-based parametrization of solar photovoltaic panels is developed and implemented in a multilayer building energy model that is fully coupled to the Weather Research and Forecasting mesoscale numerical model. We conduct a suite of sensitivity experiments (with different coverage rates of cool roof and rooftop solar photovoltaic deployment) for a 10-day clear-sky extreme heat period over the Phoenix and Tucson metropolitan areas at high spatial resolution (1-km horizontal grid spacing). Results show that deployment of cool roofs and rooftop solar photovoltaic panels reduce near-surface air temperature across the diurnal cycle and decrease daily citywide cooling energy demand. During the day, cool roofs are more effective at cooling than rooftop solar photovoltaic systems, but during the night, solar panels are more efficient at reducing the UHI effect. For the maximum coverage rate deployment, cool roofs reduced daily citywide cooling energy demand by 13-14 %, while rooftop solar photovoltaic panels by 8-11 % (without considering the additional savings derived from their electricity production). The results presented here demonstrate that deployment of both roofing technologies have multiple benefits for the urban environment, while solar photovoltaic panels add additional value because they reduce the dependence on fossil fuel consumption for electricity generation.

Analysis of materials used for Greenhouse roof covering - structure using CFD

NASA Astrophysics Data System (ADS)

Subin, M. C.; Savio Lourence, Jason; Karthikeyan, Ram; Periasamy, C.

2018-04-01

Greenhouse is widely used to create a suitable environment for the growth of plant. During summer, high temperatures cause harm to the plant. This work calculates characteristics required to optimize the above-mentioned parameters using different roof structure covering materials for the greenhouse. Moreover, this work also presents a simulation of the cooling and heating system. In addition, a computer model based on Ansys Fluent has been using to predict the temperature profiles inside the greenhouse. Greenhouse roof structure shading may have a time-dependent effect the production, water and nutrient uptake in plants. An experiment was conducted in the emirate of Dubai in United Arab Emirates to discover the impact of different materials in order to have an optimal plant growth zone and yield production. These structures were poly ethylene and poly carbonate sheets of 2 different configurations. Results showed that poly carbonate sheets configuration of optimal thickness has given a high result in terms of yield production. Therefore, there is a need for appropriate material selection of greenhouse roof structure in this area of UAE. Major parameters and properties need to be considered while selecting a greenhouse roof structure are the resistance to solar radiation, weathering, thermal as well as mechanical properties and good abrasion resistance. In the present study, an experiment has been conducted to find out the material suitability of the greenhouse roof structure in terms of developing proper ambient conditions especially to minimize the energy lose by reducing the HVAC and lighting expenses. The configuration verified using the CFD, so it has been concluded that polycarbonate can be safely used in the greenhouse than other roof structure material having white or green colour.

Analysis of urban land use in the megacity of Dhaka, Bangladesh: Roof-top detection in the context of assessing solar photovoltaic potential

NASA Astrophysics Data System (ADS)

Jaegermeyr, J.; Kabir, H.; Endlicher, W.

2009-12-01

The megacity of Dhaka, Bangladesh is considered to be one of the world’s fastest growing urban centers. With nearly 14 million people Dhaka currently faces tremendous power crisis. The available power supply of Dhaka Megacity is currently 1000-1200 MW against the maximum demand of nearly 2000 MW. The objective of this study is to classify land cover of Dhaka to locate roof-top areas which are adequate for solar photovoltaic applications. Usually this task is performed with additional building-heights data. With lack of that, we present an object-based classification approach which is based on high resolution Quickbird data only. Extensive formal buildings in Dhaka mostly have flat roof-tops made from concrete which are well suited for PV applications. The classification is focused to detect these ‘Bright Roof-Tops’ to assess a lower limit for potential PV areas. With that conservative approach bright roof-top areas of 10.554 km2 out of the city’s 134.282 km2 could be found. The overall classification accuracy is 0.918, the producer’s accuracy of ‘Bright Roof-Tops’ is 0.833. Preliminary result of the PhD work of Humayun Kabir indicates that the application of only 75 Wp stand-alone solar modules on these available bright roof-tops can generate nearly 1,000 MW of electricity. The application of solar modules with high capacity (i.e., >200 Wp) preferably through grid-connected PV systems can substantially meet-up the city’s power demand, although several techno-economic and socio-political factors are certainly involved.

Energy analysis of cool, medium, and dark roofs on residential buildings in the U.S

NASA Astrophysics Data System (ADS)

Dunbar, Michael A.

This study reports an energy analysis of cool, medium, and dark roofs on residential buildings in the U.S. Three analyses were undertaken in this study: energy consumption, economic analysis, and an environmental analysis. The energy consumption reports the electricity and natural gas consumption of the simulations. The economic analysis uses tools such as simple payback period (SPP) and net present value (NPV) to determine the profitability of the cool roof and the medium roof. The variable change for each simulation model was the roof color. The default color was a dark roof and the results were focused on the changes produced by the cool roof and the medium roof. The environmental analysis uses CO2 emissions to assess the environmental impact of the cool roof and the medium roof. The analysis uses the U.S. Department of Energy (DOE) EnergyPlus software to produce simulations of a typical, two-story residential home in the U.S. The building details of the typical, two-story U.S. residential home and the International Energy Conservation Code (IECC) building code standards used are discussed in this study. This study indicates that, when material and labor costs are. assessed, the cool roof and the medium roof do not yield a SPP less than 10 years. Furthermore, the NPV results assess that neither the cool roof nor the medium roof are a profitable investment in any climate zone in the U.S. The environmental analysis demonstrates that both the cool roof and the medium roof have a positive impact in warmer climates by reducing the CO2 emissions as much as 264 kg and 129 kg, respectively.

Urban heat mitigation by roof surface materials during the East Asian summer monsoon

NASA Astrophysics Data System (ADS)

Lee, Seungjoon; Ryu, Youngryel; Jiang, Chongya

2017-04-01

Roof surface materials, such as green and white roofs, have attracted attention in their role in urban heat mitigation, and various studies have assessed the cooling performance of roof surface materials during hot and sunny summer seasons. However, summers in the East Asian monsoon climate region are characterized by significant fluctuations in weather events, such as dry periods, heatwaves, and rainy and cloudy days. This study investigated the efficacy of different roof surface materials for heat mitigation, considering the temperatures both at and beneath the surface of the roof covering materials during a summer monsoon in Seoul, Korea. We performed continuous observations of temperature at and beneath the surface of the roof covering materials, and manual observation of albedo and the normalized difference vegetation index (NDVI) for a white roof, two green roofs (grass [Poa pratensis] and sedum [Sedum sarmentosum]), and a reference surface. Overall, the surface temperature of the white roof was significantly lower than that of the grass and sedum roofs (1.1 and 1.3°C), whereas the temperature beneath the surface of the white roof did not differ significantly from that of the grass and sedum roofs during the summer. The degree of cloudiness significantly modified the surface temperature of the white roof compared with that of the grass and sedum roofs, which depended on plant metabolisms. It was difficult for the grass to maintain its cooling ability without adequate watering management. After considering the cooling performance and maintenance efforts for different environmental conditions, we concluded that white roof performed better in urban heat mitigation than grass and sedum during the East Asian summer monsoon. Our findings will be useful in urban heat mitigation in the region.

5. Roof Truss Above Service Area, Roof Truss Above Ward, ...

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

5. Roof Truss Above Service Area, Roof Truss Above Ward, Roof Framing Axonometric - National Home for Disabled Volunteer Soldiers - Battle Mountain Sanitarium, Ward 4, 500 North Fifth Street, Hot Springs, Fall River County, SD

Unique diversity of acanthothoracid placoderms (basal jawed vertebrates) in the Early Devonian of the Prague Basin, Czech Republic: A new look at Radotina and Holopetalichthys

PubMed Central

2017-01-01

The taxonomy of Early Devonian placoderm material from the Lochkovian and Pragian of the Prague basin, previously attributed to the genera Radotina and Holopetalichthys, is revised. The Pragian species Radotina tesselata Gross 1958 shares detailed similarities with the holotype of the Lochkovian Radotina kosorensis Gross 1950, which is also the holotype of the genus; the assignation of both species to Radotina is supported. However, the Lochkovian material previously attributed to Radotina kosorensis also contains two unrecognised taxa, distinguishable from Radotina at the generic level: these are here named Tlamaspis and Sudaspis. The disputed genus Holopetalichthys, synonymised with Radotina by some previous authors, is shown to be valid. Furthermore, whereas Radotina, Tlamaspis and Sudaspis can all be assigned to the group Acanthothoracii, on the basis of several features including possession of a projecting prenasal region of the endocranium, Holopetalichthys lacks such a region and is probably not an acanthothoracid. Skull roof patterns and other aspects of morphology vary greatly between these taxa. Radotina has a substantially tesselated skull roof, whereas the skull roofs of Tlamaspis and Holopetalichthys appear to lack tesserae altogether. Tlamaspis has an extremely elongated facial region and appears to lack a premedian plate. Sudaspis has a long prenasal region, but unlike Tlamaspis the postnasal face is not elongated. Past descriptions of the braincase of 'Radotina' and the skull roofs of 'Radotina' and 'Holopetalichthys' incorporate data from more than one taxon, giving rise to spurious characterisations including an apparently extreme degree of skull roof variability. These descriptions should all be disregarded. PMID:28380002

A field study setup of four homes having non-ventilated and semi-conditioned sealed attics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, William A.; Boudreaux, Philip R.; Pallin, Simon B.

During the 2015-2016 fiscal year and with financial support from the Florida Building Commission (FBC) and the Florida Roofing and Sheet Metal Contractors Association (FRSA ), the University of Florida (UF) and the Oak Ridge National Laboratory (ORNL) completed Phase I of a study that setup four residential home demonstrations in Florida climate zones CZ-1A and CZ-2A. UF and ORNL are evaluating the hygrothermal (heat and moisture flow) performance and durability of sealed attic construction where expanded foam insulation is applied directly to the underside of the roof deck. The four homes are instrumented for measuring temperature and relative humiditymore » of the indoor living space, the outdoor air and the attic air. In addition, the temperature, relative humidity and moisture content of the roof sheathing are being monitored and recorded by remotely-accessible data acquisition equipment. Here, air leakage tests on the whole house, on the sealed attic and in the HVAC ducts were conducted on all four homes.« less

A field study setup of four homes having non-ventilated and semi-conditioned sealed attics

DOE PAGES

Miller, William A.; Boudreaux, Philip R.; Pallin, Simon B.; ...

2016-06-01

During the 2015-2016 fiscal year and with financial support from the Florida Building Commission (FBC) and the Florida Roofing and Sheet Metal Contractors Association (FRSA ), the University of Florida (UF) and the Oak Ridge National Laboratory (ORNL) completed Phase I of a study that setup four residential home demonstrations in Florida climate zones CZ-1A and CZ-2A. UF and ORNL are evaluating the hygrothermal (heat and moisture flow) performance and durability of sealed attic construction where expanded foam insulation is applied directly to the underside of the roof deck. The four homes are instrumented for measuring temperature and relative humiditymore » of the indoor living space, the outdoor air and the attic air. In addition, the temperature, relative humidity and moisture content of the roof sheathing are being monitored and recorded by remotely-accessible data acquisition equipment. Here, air leakage tests on the whole house, on the sealed attic and in the HVAC ducts were conducted on all four homes.« less

Effectiveness of Different Urban Heat Island Mitigation Methods and Their Regional Impacts

NASA Astrophysics Data System (ADS)

Zhang, N.

2017-12-01

Cool roofs and green roofs are two popular methods to mitigate urban heat island and improve urban climate. The effectiveness of different urban heat island mitigation strategies in the summer of 2013 in the Yangtze River Delta, China is investigated using the WRF (Weather Research and Forecasting) model coupled with a physically based urban canopy model. The modifications to the roof surface changed the urban surface radiation balance and then modified the local surface energy budget. Both cool roofs and green roofs led to lower surface skin temperature and near-surface air temperature. Increasing the roof albedo to 0.5 caused a similar effectiveness as covering 25% of urban roofs with vegetation; increasing roof albedo to 0.7 caused a similar near-surface air temperature decrease as 75% green roof coverage. The near-surface relative humidity increased in both cool roof and green roof experiments because of the combination of the impacts of increases in specific humidity and decreases in air temperature. The regional impacts of cool roofs and green roofs were evaluated using the regional effect index. The regional effect could be found in both near-surface air temperature and surface specific/relative humidity when the percentage of roofs covered with high albedo materials or green roofs reached a higher fraction (greater than 50%). The changes in the vertical profiles of temperature cause a more stable atmospheric boundary layer over the urban area; at the same time, the crossover phenomena occurred above the boundary layer due to the decrease in vertical wind speed.

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...

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...

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...

Impacts of shape and height of upstream roof on airflow and pollutant dispersion inside an urban street canyon.

PubMed

Huang, Yuan-Dong; He, Wen-Rong; Kim, Chang-Nyung

2015-02-01

A two-dimensional numerical model for simulating flow and pollutant dispersion in an urban street canyon is firstly developed using the FLUENT code and then validated against the wind tunnel results. After this, the flow field and pollutant dispersion inside an urban street canyon with aspect ratio W/H = 1 are examined numerically considering five different shapes (vaulted, trapezoidal, slanted, upward wedged, and downward wedged roofs) as well as three different roof height to building height ratios (Z H /H = 1/6, 1/3, and 1/2) for the upstream building roof. The results obtained reveal that the shape and height of an upstream roof have significant influences on flow pattern and pollutant distribution in an urban canyon. A large single clockwise vortex is generated in the canyon for the vaulted upstream roof at Z H /H = 1/6, 1/3, and 1/2, the trapezoidal and downward wedged roofs at Z H /H = 1/6 and 1/3, and the slanted and upward wedged roofs at Z H /H = 1/6, while a main clockwise vortex and a secondary counterclockwise vortex are established for the trapezoidal and downward wedged roofs at Z H /H = 1/2 and the slanted and upward wedged roofs at Z H /H = 1/3 and 1/2. In the one-vortex flow regime, the clockwise vortex moves upward and grows in size with increasing upstream roof height for the vaulted, trapezoidal, and downward wedged roofs. In the two-vortex flow regime, the size and rotational velocity of both upper clockwise and lower counterclockwise vortices increase with the upstream roof height for the slanted and upward wedged roofs. At Z H /H = 1/6, the pollution levels in the canyon are close among all the upstream roof shapes studied. At Z H /H = 1/3, the pollution levels in the canyon for the upward wedged roof and slanted roof are much higher than those for the vaulted, trapezoidal, and downward wedged roofs. At Z H /H = 1/2, the lowest pollution level appears in the canyon for the vaulted upstream roof, while the highest pollution level occurs in the canyon for the upward wedged roof.

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 treatments when using transparent roofs for studying drought effects, because roofs can cause significant side effects. PMID:23936480

Plant functional traits predict green roof ecosystem services.

PubMed

Lundholm, Jeremy; Tran, Stephanie; Gebert, Luke

2015-02-17

Plants make important contributions to the services provided by engineered ecosystems such as green roofs. Ecologists use plant species traits as generic predictors of geographical distribution, interactions with other species, and ecosystem functioning, but this approach has been little used to optimize engineered ecosystems. Four plant species traits (height, individual leaf area, specific leaf area, and leaf dry matter content) were evaluated as predictors of ecosystem properties and services in a modular green roof system planted with 21 species. Six indicators of ecosystem services, incorporating thermal, hydrological, water quality, and carbon sequestration functions, were predicted by the four plant traits directly or indirectly via their effects on aggregate ecosystem properties, including canopy density and albedo. Species average height and specific leaf area were the most useful traits, predicting several services via effects on canopy density or growth rate. This study demonstrates that easily measured plant traits can be used to select species to optimize green roof performance across multiple key services.

Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ueno, Kohta; Lstiburek, Joseph W.

2015-09-01

Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but duringmore » the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boudreaux, Philip; Pallin, Simon; Jackson, Roderick

We report that unvented, sealed or conditioned attics are an energy efficiency measure to reduce the thermal load of the home and decrease the space conditioning energy consumption. This retrofit is usually done by using spray polyurethane foam underneath the roof sheathing and on the gables and soffits of an attic to provide a thermal and air barrier. Unvented attics perform well from this perspective but from a moisture perspective sometimes the unvented attic homes have high interior humidity or moisture damage to the roof. As homes become more air tight and energy efficient, an understanding of the hygrothermal dynamicsmore » of the home become more important. One proposed reason for high unvented attic humidity has been that moisture can come through the asphalt shingle roof system and increase the moisture content of the roof sheathing and attic air. This has been called solar driven moisture. Oak Ridge National Laboratory (ORNL) investigated this proposed phenomenon by examining the physical properties of a roof and the physics required for the phenomenon. Results showed that there are not favorable conditions for solar driven moisture to occur. ORNL also conducted an experimental study on an unvented attic home and compared the humidity below the roof sheathing before and after a vapor impermeable underlayment was installed. There was no statistically significant difference in absolute humidity before and after the vapor barrier was installed. Finally, the outcome of the theoretical and experimental study both suggest that solar driven moisture does not occur in any significant amount.« less

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

Code of Federal Regulations, 2010 CFR

2010-07-01

..., including painting and coating of existing roofs; the construction of the sheathing or base of roofs (wood..., and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

Quality and seasonal variation of rainwater harvested from concrete, asphalt, ceramic tile and green roofs in Chongqing, China.

PubMed

Zhang, Qianqian; Wang, Xiaoke; Hou, Peiqiang; Wan, Wuxing; Li, Ruida; Ren, Yufen; Ouyang, Zhiyun

2014-01-01

There is an urgent requirement to examine the quality of harvested rainwater for potable and non-potable purposes, based on the type of roofing material. In this study, we examined the effect on the quality of harvested rainwater of conventional roofing materials (concrete, asphalt and ceramic tile roofs) compared with alternative roofing materials (green roof). The results showed that the ceramic tile roof was the most suitable for rainwater-harvesting applications because of the lower concentrations of leachable pollutants. However, in this study, the green roof was not suitable for rainwater harvesting applications. In addition, seasonal trends in water quality parameters showed that pollutants in roof runoff in summer and autumn were lower than those in winter and spring. This study revealed that the quality of harvested rainwater was significantly affected by the roofing material; therefore, local government and urban planners should develop stricter testing programs and produce more weathering resistant roofing materials to allow the harvesting of rainwater for domestic and public uses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1 1/2-Story Homes in Cold Climates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ojczyk, C.

The External Thermal and Moisture Management System (ETMMS), typically seen in deep energy retrofits, is a valuable approach for the roof-only portions of existing homes, particularly the 1 ½-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1 1/2-Story Homes in Cold Climates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ojczyk, C.

The External Thermal and Moisture Management System (ETMMS), typically seen in deep energy retrofits, is a valuable approach for the roof-only portions of existing homes, particularly the 1 1/2-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

Iraqi Army Facilities Under the Iraq Security Forces Fund, Diyanah and Debecha, Iraq

DTIC Science & Technology

2008-01-17

reinforcement bars and cast each building’s roof flatwork and horizontal beams to complete the structural aspects of the roof system . Steel header...included a mix of new construction and renovation of existing structures and facilities. The Statement of Requirements and Specifications provided...that renovation of existing structures , when possible, was preferred. In addition, the United States government encouraged the contractor to use

Aerosol Attenuation in the 2-4 Micrometer Region

DTIC Science & Technology

1975-03-01

Company Model 911ir dew point hydrometer. The lithium chloride sensors will be placed on the roof where the aerosol is sampled and at the entrance...Extinction Measurement il External View of 400 Meter White Cell 13 Primary Aerosol and Gas Handlinfe Systems 14 Calibration for Extinction...Massacusetts. Aerosol-laden air will be drawn into the experimental apparatus from a point 10 ft above the roof of the building. A continuoush

A Roof for the Lions' House

NASA Technical Reports Server (NTRS)

1978-01-01

Fans of the National Football League s Detroit Lions don't worry about game day 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.The team of DuPont, Chemical Fabrics and Birdair have collaborated on a number of fabric structures. Some are supported by air pressure, others by cables alone. Most of the structures are in the recreational category. With conventional construction costs still on the upswing, you're likely to see a great many more permanent facilities enclosed by the aerospace spinoff fabric.

Harnessing solar pressure to slew and point large infrared space telescopes

NASA Astrophysics Data System (ADS)

Errico, Simona; Angel, Roger P.; Calvert, Paul D.; Woof, Neville

2003-03-01

Large astronomical Gossamer telescopes in space will need to employ large solar shields to safeguard the optics from solar radiation. These types of telescopes demand accurate controls to maintain telescope pointing over long integration periods. We propose an active solar shield system that harnesses radiation pressure to accurately slew and acquire new targets without the need for reaction wheels or thrusters. To provide the required torques, the solar shield is configured as an inverted, 4-sided pyramidal roof. The sloped roof interior surfaces are covered with hinged “tiles” made from piezoelectric film bimorphs with specular metallized surfaces. Nominally, the tiles lie flat against the roof and the sunlight is reflected outward equally from all sloped surfaces. However, when the tiles on one roof pitch are raised, the pressure balance is upset and the sunshade is pushed to one side. By judicious selection of the tiles and control of their lift angle, the solar pressure can be harvested to stabilize the spacecraft orientation or to change its angular momentum. A first order conceptual design performance analysis and the results from the experimental design, fabrication and testing of piezoelectric bimorph hinge elements will be presented. Next phase challenges in engineering design, materials technology, and systems testing will be discussed.

129. ARAII Administrative and technical support building (ARA606) sections showing ...

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

129. ARA-II Administrative and technical support building (ARA-606) sections showing roof and wall details and longitudinal section. C.A. Sundberg and Associates 866-area/ALPR-606-A-5. Date: May 1958. Ineel index code no. 070-0606-00-822-102828. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

What land covers are effective in mitigating a heat island in urban building rooftop?

NASA Astrophysics Data System (ADS)

Lee, S.; Ryu, Y.

2014-12-01

Since the 20th century, due to the rapid urbanization many urban environment problems have got blossomed and above all heat island has been recognized as an important issue. There are several causes of urban heat island, but land cover change occupies the largest portion of them. Owing to urban expansion, vegetation is changed into asphalt pavements and concrete buildings, which reduces latent heat flux. To mitigate the problems, people enlarge vegetation covers such as planting street trees, making rooftop gardens and constructing parks or install white roofs that feature high albedo on a building. While the white roofs reflect about 70% of solar radiation and absorb less radiation, vegetation has low albedo but cools the air through transpiration and fixes carbon dioxide through photosynthesis. There are some studies concerning which one is more effective to mitigate heat island between the green roof and white roof. This study compares the green roof and white roof and additionally considers carbon fixation that has not been treated in other studies. Furthermore, this study ascertains an efficiency of solar-cell panel that is used for building roof recently. The panel produces electric power but has low albedo which could warm the air. The experiment is conducted at the rooftop in Seoul, Korea and compares green roof (grass), white roof (painted cover), black roof (solar panel) and normal painted roof. Surface temperature and albedo are observed for the four roof types and incoming shortwave, outgoing longwave and carbon flux are measured in green roof solely. In the case of solar panels, the electricity generation is calculated from the incoming radiation. We compute global warming potentials for the four roof types and test which roof type is most effective in reducing global warming potential.

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 roofing industry and experienced installers for future green roof construction.

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 roofing industry and experienced installers for future green roof construction.

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. Copyright © 2011 Elsevier Ltd. All rights reserved.

Inactivation of faecal indicator bacteria in a roof-captured rainwater system under ambient meteorological conditions.

PubMed

Ahmed, W; Richardson, K; Sidhu, J P S; Jagals, P; Toze, S

2014-01-01

In this study, faecal indicator bacteria (FIB) namely Escherichia coli and Enterococcus spp. were seeded into slurries of possum faeces and placed on the roof and in the gutter of a roof-captured rainwater (RCR) system. The persistence of FIB in these circumstances was determined under ambient climatic conditions. FIB persistence was also determined under in situ conditions in tank water using diffusion chambers. The numbers of surviving FIB at different time intervals were enumerated using culture-based methods. Both FIB were rapidly inactivated on the roof under sunlight conditions (T(90) = 2 h) compared with shade conditions (T(90) = 9-53 h). Significant differences were observed between sunlight and shade conditions on the roof for both T90 values of E. coli (P < 0·001) and Enterococcus spp. (P < 0·001). E. coli showed biphasic inactivation patterns under both clean and unclean gutter conditions. Enterococcus spp., however, showed rapid inactivation (T(90) = 2 h for the clean gutter and T(90) = 6 h for the unclean gutter) compared with E. coli (T(90) = 22 h for the clean gutter and T(90) = 20 h for the unclean gutter). Significant differences were also observed between the T(90) values of E. coli and Enterococcus spp. for both clean (P < 0·001) and unclean (P < 0·001) gutters. Both E. coli and Enterococcus spp. showed nonlinear biphasic inactivation in tank water. Significant difference was observed between the T(90) value of E. coli inactivation compared with Enterococcus spp. (P < 0·001) in the tank water. In this study, FIB were observed to survive longer (T(90) = 9-53 h) on the roof under shade conditions compared with sunlight conditions (T(90) = 2 h). If there is a rainfall event within two to three days after the deposition of faecal maters on the roof, it is highly likely that FIB would be transported to the tank water. When introduced into the tank, a relatively slow inactivation process may take place (T(90) = 38-72 h). The presence of FIB in water indicates faecal pollution and potential presence of enteric pathogens. Therefore, the information on the resilience of FIB, as obtained in this study, can be used for indirect assessment of health risks associated with using roof-captured rainwater for potable and nonpotable purposes. © 2013 The Society for Applied Microbiology.

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

Code of Federal Regulations, 2013 CFR

2013-07-01

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

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

Code of Federal Regulations, 2012 CFR

2012-07-01

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

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

Code of Federal Regulations, 2014 CFR

2014-07-01

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

Eco-Environmental Factors in Green Roof Application in Indian Cities

NASA Astrophysics Data System (ADS)

Mukherjee, M.

2014-09-01

Green-roof is the cost-effective environmental mitigation strategy for urban areas [1]. Its application is limited in India primarily due to inadequate understanding about its cost-benefit analysis and technicalities of its maintenance. Increasing awareness about green roof can alter conservative attitude towards its application. So, this work presents a quantified study on green-roof types, cost and environmental benefits while considering different geo-urban climate scenarios for cities of Kolkata, Mumbai, Chennai and New Delhi. Cost estimation for extensive and intensive green-roof with reference to commonly used roof in urban India is also worked out. Attributes considered for environmental discussion are energy savings related to thermal heat gain through roof, roof-top storm-water drainage and sound attenuation. The comparative study confirms that further focused study on individual cities would identify city-specific objectives for green-roof application; strategies like awareness, capacity building programmes, incentives, demonstration projects etc. can be worked out accordingly for wider application of green-roof in Indian cities.

Potential Application of Shallow Bed Wetland Roof systems for green urban cities

NASA Astrophysics Data System (ADS)

Bui, X. T.

2016-12-01

This study aims to investigate the growth, nutrient uptake, domestic wastewater treatment, green (leaf) area and heat reduction of four shallow subsurface flow wetland roof (WR) systems with four different new local plants. Selected species included Cyperus Javanicus Hot (WR1), Eleusine Indica (L.) Gaertn (WR2), Struchium Sparganophorum (L.) Kuntze (WR3) and Kyllinga Brevifolia Rottb (WR4). These systems were operated during 61 days at hydraulic loading rates of 353 - 403 m3/ha.day. The biomass growth of 4.9-73.7g fresh weight/day, and 0.8-11.4 g dry weight/day were observed. The nutrient accumulation according to dry biomass achieved 0.25-2.14% of total nitrogen (TN) and 0.13-1.07% of total phosphorus (TP). The average COD, TN and TP removal was 61-79%; 54-81% and 62-83%, which corresponding to 27-33 kg COD/ha.day, 10-14 kg TN/ha.day and 0.4-0.5 kg TP/ha.day, respectively. The WR4 system achieved the highest COD and TN removal among the WRs. The TP removal efficiency showed an insignificant difference for the systems. Consequently, the treated water quality complied with the Vietnam standard limits (QCVN 14:2008, level B). The green area of the four plants varied between 63-92 m2 green leaf/m2 WR. The WR4 was the highest green area. Moreover, the results also showed the temperature under the flat roof was 1-3°C lower than that of the ambient air. In summary, wetland roof is a promising technology, which not only owns the effective domestic wastewater treatment capacity, but also contributes to green urban with several above benefits.

15. The second story in the north segment of the ...

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

15. The second story in the north segment of the building was originally constructed as a restaurant. The north wall of the dining room retains the original wood wainscot and double-hung windows. At some undetermined time, a building was constructed on the adjacent property; blocking the windows in the dining room. Several chimneys with stove-pipe connections occur in the room. The members seen on the floor are part of a system recently installed to support the failing roof. Credit GADA/MRM. - Stroud Building, 31-33 North Central Avenue, Phoenix, Maricopa County, AZ

A hybrid active/passive exhaust noise control system for locomotives.

PubMed

Remington, Paul J; Knight, J Scott; Hanna, Doug; Rowley, Craig

2005-01-01

A prototype hybrid system consisting of active and passive components for controlling far-field locomotive exhaust noise has been designed, assembled, and tested on a locomotive. The system consisted of a resistive passive silencer for controlling high-frequency broadband noise and a feedforward multiple-input, multiple-output active control system for suppressing low-frequency tonal noise. The active system used ten roof-mounted bandpass speaker enclosures with 2-12-in. speakers per enclosure as actuators, eight roof-mounted electret microphones as residual sensors, and an optical tachometer that sensed locomotive engine speed as a reference sensor. The system was installed on a passenger locomotive and tested in an operating rail yard. Details of the system are described and the near-field and far-field noise reductions are compared against the design goal.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 formore » 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.« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ueno, K.; Lstiburek, J. W.

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.more » 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).« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.more » 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).« less

Skylight energy performance and design optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arasteh, D.; Johnson, R.; Selkowitz, S.

1984-02-01

Proper skylight utilization can significantly lower energy requirements and peak electrical loads for space conditioning and lighting in commercial buildings. In this study we systematically explore the energy effects of skylight systems in a prototypical office building and examine the savings from daylighting. The DOE-2.1B energy analysis computer program with its newly incorporated daylighting algorithms was used to generate more than 2000 parametric simulations for seven US climates. The parameters varied include skylight-to-roof ratio, shading coefficient, visible transmittance, skylight well light loss, electric lighting power density, roof heat transfer coefficient, and type of electric lighting control. For specific climates wemore » identify roof/skylight characteristics that minimize total energy or peak electrical load requirements.« less

Preventing a Washout.

ERIC Educational Resources Information Center

Poindexter, Dave

1996-01-01

Offers ideas for locating a roof leak. Discusses why many leaks originate in the roof's base flashings and the importance of knowing the roof's material makeup. Advocates keeping a roof-leak history and gives advice on performing inspections to check for leaks. Discusses how to find small holes in roofs. (RJM)

Decoupling factors affecting plant diversity and cover on extensive green roofs.

PubMed

MacIvor, J Scott; Margolis, Liat; Puncher, Curtis L; Carver Matthews, Benjamin J

2013-11-30

Supplemental irrigation systems are often specified on green roofs to ensure plant cover and growth, both important components of green roof performance and aesthetics. Properties of the growing media environment too can alter the assemblage of plant species able to thrive. In this study we determine how plant cover, above ground biomass and species diversity are influenced by irrigation and growing media. Grass and forb vegetative cover and biomass were significantly greater in organic based growing media but there was no effect of supplemental irrigation, with two warm season grasses dominating in those treatments receiving no supplemental irrigation. On the other hand, plant diversity declined without irrigation in organic media, and having no irrigation in inorganic growing media resulted in almost a complete loss of cover. Sedum biomass was less in inorganic growing media treatments and species dominance shifted when growing media organic content increased. Our results demonstrate that supplemental irrigation is required to maintain plant diversity on an extensive green roof, but not necessarily plant cover or biomass. These results provide evidence that planting extensive green roofs with a mix of plant species can ensure the survival of some species; maintaining cover and biomass when supplemental irrigation is turned off to conserve water, or during extreme drought. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Morphological changes on development of Tenebrio molitor L. (Coleoptera: Tenebrionidae) in rearing room system, free air CO2 enrichment system and open roof ventilation system

NASA Astrophysics Data System (ADS)

Ramli, Nur Hasyimah; Yaakop, Salmah

2018-04-01

Tenebrio molitor known as darkling beetle is burrowing insects and can be found all over the world. Tenebrio molitor samples were put in Open Roof Ventilation System, Free Air CO2 Enrichment and Rearing Room system. The development of Tenebrio molitor adult parents (P) and first generation (F1) that more exposed to high level of CO2 were studied. As the results, parent and first generation (F1) of T. molitor shows that there are no significant effects of CO2 on their development. But, decreased development pattern showed between parent and F1 can be used to estimate that prolonged exposure of CO2 will change their development. The highest development of parent showed by OFVSP (0.1708±0.0013) mm, while the lowest showed by FACEP (0.1686±0.0013) mm. For F1, the highest development showed by OFVS F1 (0.1705±0.0015) mm, while RR F1 becomes the lowest (0.1649±0.0023) mm. No significant difference shown by ANOVA test. Unfortunately, the data cannot be used to prove that the development of parent and F1 were affected by CO2 because no significant difference recorded between them. Correlation coefficient analysis of OFVSP and OFVS F1 presented to support the results. It shows that the correlation coefficient among characters from parents and F1 are different. Further study should be done in future to increase our knowledge of the climate change on insects.

A ROle-Oriented Filtering (ROOF) approach for collaborative recommendation

NASA Astrophysics Data System (ADS)

Ghani, Imran; Jeong, Seung Ryul

2016-09-01

In collaborative filtering (CF) recommender systems, existing techniques frequently focus on determining similarities among users' historical interests. This generally refers to situations in which each user normally plays a single role and his/her taste remains consistent over the long term. However, we note that existing techniques have not been significantly employed in a role-oriented context. This is especially so in situations where users may change their roles over time or play multiple roles simultaneously, while still expecting to access relevant information resources accordingly. Such systems include enterprise architecture management systems, e-commerce sites or journal management systems. In scenarios involving existing techniques, each user needs to build up very different profiles (preferences and interests) based on multiple roles which change over time. Should this not occur to a satisfactory degree, their previous information will either be lost or not utilised at all. To limit the occurrence of such issues, we propose a ROle-Oriented Filtering (ROOF) approach focusing on the manner in which multiple user profiles are obtained and maintained over time. We conducted a number of experiments using an enterprise architecture management scenario. In so doing, we observed that the ROOF approach performs better in comparison with other existing collaborative filtering-based techniques.

25. Detail, roof at junction of main roof and tower ...

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

25. Detail, roof at junction of main roof and tower skirt roof; note condition of slates, subroof, missing gutter, lead pipe gutter outlet; view to northwest from lift-bed truck, 135mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... proximity to a roof, including carpentry and metal work, alterations, additions, maintenance and repair... or metal), including roof trusses or joists; gutter and downspout work; the installation and... work performed in connection with the installation of roofs, including related metal work such as...

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

Experimental research on coalbed gas drainage effect and economy of long directional borehole in roof

NASA Astrophysics Data System (ADS)

Yang, Huiming; Hu, Liangping

2017-05-01

In order to study the coalbed gas drainage effect and economy of long directional roof borehole, 2 boreholes were laid out in Xinji No. 2 mine to analyze its gas drainage and investment costs comparing with high position roof borehole and high position roof roadway. The result indicates that the long directional roof borehole save investment by 44.8% and shorten the construction period by 30%, comparing with high position roof roadway for controlling gas in the working face. Investment slightly less and shorten the construction period by 47.5%, comparing with the roof high position borehole. Therefore, the method of the long directional roof borehole to drain coalbed gas in working face is the most cost-effective.

Thermal performance of a Concrete Cool Roof under different climatic conditions of Mexico

DOE PAGES

Hernández-Pérez, I.; Álvarez, G.; Gilbert, H.; ...

2014-11-27

A cool roof is an ordinary roof with a reflective coating on the exterior surface which has a high solar reflectance and high thermal emittance. These properties let the roof keep a lower temperature than a standard roof under the same conditions. In this work, the thermal performance of a concrete roof with and without insulation and with two colors has been analyzed using the finite volume method. The boundary conditions of the external roof surface were taken from hourly averaged climatic data of four cities. For the internal surface, it is considered that the building is air-conditioned and themore » inside air has a constant temperature. The interior surface temperature and the heat flux rates into the roofs were obtained for two consecutive days in order to assess the benefits of a cool roofs in different climates.« less

Nutrient leaching from extensive green roofs with different substrate compositions: a laboratory study.

PubMed

Zhang, Wei; Zhong, Xing; Che, Wu

2018-02-01

To investigate nutrient leaching from extensive green roofs, green roof platforms were established to investigate the effluent quantity and quality during artificial rainfall. When the influent volume reached three times the empty bed volume, for which the cumulative rainfall was around 300 mm, the effluent TP and COD concentrations of green roof platforms filled with peat soil did not tend to stabilize. For a long-term operation, the substrate depths had little significant influence on TN, TP and COD concentrations of the green roof effluents. A normalized cumulative emission process method was proposed to discuss the difference in various pollutant leaching processes. Obvious differences in the leaching process of different contaminants for green roof platforms filled with various substrates were observed. For the green roof filled with modified substrates, the nitrogen and phosphorus pollutant leaching rates were relatively high in the initial stage of green roof operation and the phosphorus leaching rate was higher than that of nitrogen. The green roof is a sink for TN, but not for TP and COD in this study. The outcomes are critical for the selection of green roof substrates and also contribute to green roof maintenance.

Combating the Urban Heat Island Effect: Results from a Long-Term Monitoring Study on Urban Green, White, and Black Roofs in New York City

NASA Astrophysics Data System (ADS)

Gaffin, S. R.; Kong, A. Y.; Hartung, E.; Hsu, B.; Roditi, A.; Rosenzweig, C.

2011-12-01

Urban heat island mitigation strategies include increasing urban vegetation and increasing the albedo of impervious surfaces. Vegetated "green" roofs can provide benefits to stormwater management, water quality, energy cost efficiency, and biodiversity in cities, but the body of research on green roofs in the US is not large and cities in the US have been slow to adopt green roofs. On the other hand, "high-albedo" white roofs have been applied more widely through projects such as New York City Cool Roofs. There are several major issues (e.g., albedo decline, product differences, and long-term temperature controls) about green and white roof performance versus typical black roofs with respect to urban heat island mitigation that have yet to be fully addressed. Here, we present data from an on-going, long-term study in New York City in which pilot, urban albedo enhancement and vegetation effects have been monitored at the building-scale since 2007. Although the urban heat island effect can be detected throughout the year, our objective for this paper was to compare green roof vegetation with those of the high-albedo roofs for their ability to reduce the electricity demand for cooling in the summer. Using energy balance methodology across our sites (three), we found that green and white roof membrane temperature peaks are on average 60°F (33°C) and 30° F (17°C), respectively, cooler than black roof temperature peaks, and that these alternative surfaces significantly reduce thermal stress to roof membranes. Interestingly, we found that industrial white membranes [thermoplastic polyolefin (TPO) and ethylene propylene diene monomer (EPDM)] stay cleaner longer, thereby, maintaining the high-albedo benefits longer than the painted roofs, which tend to lose their albedo properties rapidly. Results thus far suggest that more long-term research comparing the albedo and cooling benefits of green and white roofs to black roofs is necessary to understand temporal changes to roof performance.

Using Remote Sensing to Quantify Roof Albedo in Seven California Cities

NASA Astrophysics Data System (ADS)

Ban-Weiss, G. A.; Woods, J.; Millstein, D.; Levinson, R.

2013-12-01

Cool roofs reflect sunlight and therefore can reduce cooling energy use in buildings. Further, since roofs cover about 20-25% of cities, wide spread deployment of cool roofs could mitigate the urban heat island effect and partially counter urban temperature increases associated with global climate change. Accurately predicting the potential for increasing urban albedo using reflective roofs and its associated energy use and climate benefits requires detailed knowledge of the current stock of roofs at the city scale. Until now this knowledge has been limited due to a lack of availability of albedo data with sufficient spatial coverage, spatial resolution, and spectral information. In this work we use a novel source of multiband aerial imagery to derive the albedos of individual roofs in seven California cities: Los Angeles, Long Beach, San Diego, Bakersfield, Sacramento, San Francisco, and San Jose. The radiometrically calibrated, remotely sensed imagery has high spatial resolution (1 m) and four narrow (less than 0.1 μm wide) band reflectances: blue, green, red, and near-infrared. To derive the albedo of roofs in each city, we first locate roof pixels within GIS building outlines. Next we use laboratory measurements of the solar spectral reflectances of 190 roofing products to empirically relate solar reflectance (albedo) to reflectances in the four narrow bands; the root-mean-square of the residuals for the albedo prediction is 0.016. Albedos computed from remotely sensed reflectances are calibrated to ground measurements of roof albedo in each city. The error (both precision and accuracy) of albedo values is presented for each city. The area-weighted mean roof albedo (× standard deviation) for each city ranges from 0.17 × 0.08 (Los Angeles) to 0.29 × 0.15 (San Diego). In each city most roofs have low albedo in the range of 0.1 to 0.3. Roofs with albedo greater than 0.4 comprise less than 3% of total roofs and 7% of total roof area in each city. The California Building Energy Efficiency Standard (Title-24, Part 6) includes the use of high-albedo surfaces on low-sloped roofs on non-residential buildings. Analyzing a subset of large presumably commercial buildings, we find high albedo roofs represent 0.5% and 10% of total roofs and roof surface area, respectively. The potential for high albedo roofs to reduce urban temperatures was investigated for a California city (Bakersfield) with warm summers using a state-of-the-art meteorological model (Weather Research and Forecasting, WRF). Base case and cool roof scenarios were simulated with the only difference being that the surface albedo was increased under the cool roof scenario. Roof albedos derived from the aerial imagery were used as an input to the climate model in the base case scenario. Simulation results indicate that seasonal average afternoon (1500 h) temperatures could be reduced by up to 0.2 °C across Bakersfield during both the summer and winter. While temperature changes are similar during winter and summer, only summer shows statistically significant temperature changes downwind (southeast) from Bakersfield. This indicates that reduced summertime temperatures may be felt over a distance that is 2 or 3 times the length scale of the region with high albedo roofs.

Using Cool Roofs to Reduce Energy Use, Greenhouse Gas Emissions, and Urban Heat-island Effects: Findings from an India Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akbari, Hashem; Xu, Tengfang; Taha, Haider

Cool roofs, cool pavements, and urban vegetation reduce energy use in buildings, lower local air pollutant concentrations, and decrease greenhouse gas emissions from urban areas. This report summarizes the results of a detailed monitoring project in India and related simulations of meteorology and air quality in three developing countries. The field results quantified direct energy savings from installation of cool roofs on individual commercial buildings. The measured annual energy savings potential from roof-whitening of previously black roofs ranged from 20-22 kWh/m2 of roof area, corresponding to an air-conditioning energy use reduction of 14-26% in commercial buildings. The study estimated thatmore » typical annual savings of 13-14 kWh/m2 of roof area could be achieved by applying white coating to uncoated concrete roofs on commercial buildings in the Metropolitan Hyderabad region, corresponding to cooling energy savings of 10-19%. With the assumption of an annual increase of 100,000 square meters of new roof construction for the next 10 years in the Metropolitan Hyderabad region, the annual cooling energy savings due to whitening concrete roof would be 13-14 GWh of electricity in year ten alone, with cumulative 10-year cooling energy savings of 73-79 GWh for the region. The estimated savings for the entire country would be at least 10 times the savings in Hyderabad, i.e., more than 730-790 GWh. We estimated that annual direct CO2 reduction associated with reduced energy use would be 11-12 kg CO2/m2 of flat concrete roof area whitened, and the cumulative 10-year CO2 reduction would be approximately 0.60-0.65 million tons in India. With the price of electricity estimated at seven Rupees per kWh, the annual electricity savings on air-conditioning would be approximately 93-101 Rupees per m2 of roof. This would translate into annual national savings of approximately one billion Rupees in year ten, and cumulative 10-year savings of over five billion Rupees for cooling energy in India. Meteorological simulations in this study indicated that a reduction of 2C in air temperature in the Hyderabad area would be likely if a combination of increased surface albedo and vegetative cover are used as urban heat-island control strategies. In addition, air-temperature reductions on the order of 2.5-3.5C could be achieved if moderate and aggressive heat-island mitigation measures are adopted, respectively. A large-scale deployment of mitigation measures can bring additional indirect benefit to the urban area. For example, cooling outside air can improve the efficiency of cooling systems, reduce smog and greenhouse gas (GHG) emissions, and indirectly reduce pollution from power plants - all improving environmental health quality. This study has demonstrated the effectiveness of cool-roof technology as one of the urban heat-island control strategies for the Indian industrial and scientific communities and has provided an estimate of the national energy savings potential of cool roofs in India. These outcomes can be used for developing cool-roof building standards and related policies in India. Additional field studies, built upon the successes and lessons learned from this project, may be helpful to further confirm the scale of potential energy savings from the application of cooler roofs in various regions of India. In the future, a more rigorous meteorological simulation using urbanized (meso-urban) meteorological models should be conducted, which may produce a more accurate estimate of the air-temperature reductions for the entire urban area.« less

Methodology for Identifying and Quantifying Metal Pollutant Sources in Storm Water Runoff

DTIC Science & Technology

2015-02-01

sanitary sewer are not viable options. In addition, visual inspections of the drainage areas have been insufficient in identifying and quantifying the...diverting the runoff into the sanitary sewer system, but the cost could exceed millions of dollars. Instead of capturing and treating all stormwater...Unknown Appears only if Building Siding is “metal” Roof Material roof_mat_d Built Up, Metal Panel, Asphalt, Fabric, Clay , Slate, Wood, Other

KSC-04pd1774

NASA Image and Video Library

2004-09-10

KENNEDY SPACE CENTER, FLA. - Members of a hurricane assessment team from Johnson Space Center and Marshall Space Flight Center observe the damage to the roof of the Thermal Protection System (TPS) Facility at KSC after Hurricane Frances hit the east coast of Central Florida and Kennedy Space Center. The facility, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, is almost totally unserviceable at this time after losing approximately 35 percent of its roof. Equipment and materials that survived the storm have been relocated to the RLV hangar near the KSC Shuttle Landing Facility.

Generalised monogamy relation of convex-roof extended negativity in multi-level systems

NASA Astrophysics Data System (ADS)

Tian, Tian; Luo, Yu; Li, Yongming

2016-11-01

In this paper, we investigate the generalised monogamy inequalities of convex-roof extended negativity (CREN) in multi-level systems. The generalised monogamy inequalities provide the upper and lower bounds of bipartite entanglement, which are obtained by using CREN and the CREN of assistance (CRENOA). Furthermore, we show that the CREN of multi-qubit pure states satisfies some monogamy relations. Additionally, we test the generalised monogamy inequalities for qudits by considering the partially coherent superposition of a generalised W-class state in a vacuum and show that the generalised monogamy inequalities are satisfied in this case as well.

Generalised monogamy relation of convex-roof extended negativity in multi-level systems

PubMed Central

Tian, Tian; Luo, Yu; Li, Yongming

2016-01-01

In this paper, we investigate the generalised monogamy inequalities of convex-roof extended negativity (CREN) in multi-level systems. The generalised monogamy inequalities provide the upper and lower bounds of bipartite entanglement, which are obtained by using CREN and the CREN of assistance (CRENOA). Furthermore, we show that the CREN of multi-qubit pure states satisfies some monogamy relations. Additionally, we test the generalised monogamy inequalities for qudits by considering the partially coherent superposition of a generalised W-class state in a vacuum and show that the generalised monogamy inequalities are satisfied in this case as well. PMID:27857163

Generalised monogamy relation of convex-roof extended negativity in multi-level systems.

PubMed

Tian, Tian; Luo, Yu; Li, Yongming

2016-11-18

In this paper, we investigate the generalised monogamy inequalities of convex-roof extended negativity (CREN) in multi-level systems. The generalised monogamy inequalities provide the upper and lower bounds of bipartite entanglement, which are obtained by using CREN and the CREN of assistance (CRENOA). Furthermore, we show that the CREN of multi-qubit pure states satisfies some monogamy relations. Additionally, we test the generalised monogamy inequalities for qudits by considering the partially coherent superposition of a generalised W-class state in a vacuum and show that the generalised monogamy inequalities are satisfied in this case as well.

Effectiveness of foam-based and traditional green roofs in reducing nitrogen, phosphorus, organic carbon and suspended solids in urban installations

NASA Astrophysics Data System (ADS)

MacAvoy, S. E.; Mucha, S.; Williamson, G.

2017-12-01

While green roofs have well understood benefits for retaining runoff, there is less of a consensus regarding the potential for retaining and absorbing nutrients or suspended solids from roof runoff that would otherwise travel to waterways. Additionally, there are numerous designs, materials and maintenance plans associated with "green" roofs/surfaces that may greatly impact not only their hydrological benefit but also their pollution mitigation potential. Here we examine the NO3, NH4, total organic carbon (TOC), total phosphorus (TP) and total suspended solids (TSS) retention potential from planted and unplanted foam roofs and traditional soil roofs. Direct precipitation, untreated runoff and throughflow from the different roof types were collected for 3 to 11 rain events over a year (depending on roof). Unplanted and traditional roofs reduced TSS by 80% or better relative to runoff. Traditional roofs showed 50% lower TP than runoff or other roof types. TOC was higher than direct precipitation for all treatments, although there were no differences among the treatments themselves. Taken as averages over the 11 events, NO3 and NH4 concentrations were highly variable for runoff and treatments and significant differences were not detected. Preliminary analysis suggests there were no differences between performance of traditional versus foam-based roofs, although a greater sample size is required to be definitive.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 metalmore » 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.« less

Impact of aerial infrared roof moisture scans on the U.S. Army's ROOFER program

NASA Astrophysics Data System (ADS)

Knehans, Al; Ledford, Jim

1993-04-01

The ROOFER program is being used by the U.S. Army to inspect and evaluate its built-up and single-ply membrane roofs. The results of the inspection effort are used to develop an overall roof condition index. The condition of the roof insulation can greatly alter the final condition index. By using an aerial infrared (IR) roof moisture scan, all the insulated roofs at most Army installations can be effectively surveyed in a very short time. The aerial scans have detected numerous areas of wet roof insulation, which has had a profound impact on the results of the ROOFER program. The scans have also provided management personnel with more accurate analysis as to the actual condition of the installation's insulated roofs.

Influence of the Roof Movement Control Method on the Stability of Remnant

NASA Astrophysics Data System (ADS)

Adach-Pawelus, Karolina

2017-12-01

In the underground mines, there are geological and mining situations that necessitate leaving behind remnants in the mining field. Remnants, in the form of small, irregular parcels, are usually separated in the case of: significant problems with maintaining roof stability, high rockburst hazard, the occurrence of complex geological conditions and for random reasons (ore remnants), as well as for economic reasons (undisturbed rock remnants). Remnants left in the mining field become sites of high stress values concentration and may affect the rock in their vicinity. The values of stress inside the remnant and its vicinity, as well as the stability of the remnant, largely depend on the roof movement control method used in the mining field. The article presents the results of the numerical analysis of the influence of roof movement control method on remnant stability and the geomechanical situation in the mining field. The numerical analysis was conducted for the geological and mining conditions characteristic of Polish underground copper mines owned by KGHM Polska Miedz S.A. Numerical simulations were performed in a plane strain state by means of Phase 2 v. 8.0 software, based on the finite element method. The behaviour of remnant and rock mass in its vicinity was simulated in the subsequent steps of the room and pillar mining system for three types of roof movement control method: roof deflection, dry backfill and hydraulic backfill. The parameters of the rock mass accepted for numerical modelling were calculated by means of RocLab software on the basis of the Hoek-Brown classification. The Mohr-Coulomb strength criterion was applied.

Initial measurement of site boundary neutron dose and comparison with calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

P. Degtyarenko; D. Dotson; R. May

1996-10-01

For most accelerators adequate side shielding can be provided at minimal cost to meet the most aggressive radiation protection regulations and, further, the likely requirement to increase shielding thickness still more at a later date can be done usually by heaping more earth or applying local shielding at minimal expense and inconvenience. This moderately happy state of affairs does not unfortunately hold true with roof shielding. The cost of roof shielding is largely predicated on the roof span and the necessary structural engineering requirements for its support. These measures can be extremely expensive and where one is dealing with themore » rather extensive unsupported spans typical of experimental halls devoted to experiments with high energy electron beams; it is necessary to specify the roof thickness as carefully as possible with the constant concern that adding more earth later is not likely to be possible without rebuilding the hall. Because of the nature of roof skyshine, and for most high energy accelerator facilities neutron skyshine, the effect of the radiation is likely to extend to the facility fence-line where one is concerned about the exposure of the general population. Very properly the dose limit for the general population is set at a rather low value (1 mSv y{sup {minus}1}) and in order for the Jefferson Lab (JLab) to ensure strict compliance with this limit they have a design goal for the fence line of 0.1 mSv y{sup {minus}1}. However, because natural neutron backgrounds are low (30--40 {micro}Sv y{sup {minus}1}) and the methods of detection and measurement permit rejection of background interference from photons, they can measure the JLab produced neutron radiation with good sensitivity and precision.« less

Mechanisms of differentiation in the Skaergaard magma chamber

NASA Astrophysics Data System (ADS)

Tegner, C.; Lesher, C. E.; Holness, M. B.; Jakobsen, J. K.; Salmonsen, L. P.; Humphreys, M. C. S.; Thy, P.

2012-04-01

The Skaergaard intrusion is a superb natural laboratory for studying mechanisms of magma chamber differentiation. The magnificent exposures and new systematic sample sets of rocks that solidified inwards from the roof, walls and floor of the chamber provide means to test the relative roles of crystal settling, diffusion, convection, liquid immiscibility and compaction in different regions of the chamber and in opposite positions relative to gravity. Examination of the melt inclusions and interstitial pockets has demonstrated that a large portion of intrusion crystallized from an emulsified magma chamber composed of immiscible silica- and iron-rich melts. The similarity of ratios of elements with opposite partitioning between the immiscible melts (e.g. P and Rb) in wall, floor and roof rocks, however, indicate that large-scale separation did not occur. Yet, on a smaller scale of metres to hundred of metres and close to the interface between the roof and floor rocks (the Sandwich Horizon), irregular layers and pods of granophyre hosted by extremely iron-rich cumulates point to some separation of the two liquid phases. Similar proportions of the primocryst (cumulus) minerals in roof, wall and floor rocks indicate that crystal settling was not an important mechanism. Likewise, the lack of fractionation of elements with different behavior indicate that diffusion and fluid-driven metasomatism played relatively minor roles. Compositional convection and/or compaction within the solidifying crystal mush boundary layer are likely the most important mechanisms. A correlation of low trapped liquid fractions (calculated from strongly incompatible elements) in floor rocks with high fractionation density (the density difference between the crystal framework and the liquid) indicate that compaction is the dominating process in expelling evolved liquid from the crystal mush layer. This is supported by high and variable trapped liquid contents in the roof rocks, where gravity-driven compaction will not work.

A Tightly-Coupled GPS/INS/UWB Cooperative Positioning Sensors System Supported by V2I Communication

PubMed Central

Wang, Jian; Gao, Yang; Li, Zengke; Meng, Xiaolin; Hancock, Craig M.

2016-01-01

This paper investigates a tightly-coupled Global Position System (GPS)/Ultra-Wideband (UWB)/Inertial Navigation System (INS) cooperative positioning scheme using a Robust Kalman Filter (RKF) supported by V2I communication. The scheme proposes a method that uses range measurements of UWB units transmitted among the terminals as augmentation inputs of the observations. The UWB range inputs are used to reform the GPS observation equations that consist of pseudo-range and Doppler measurements and the updated observation equation is processed in a tightly-coupled GPS/UWB/INS integrated positioning equation using an adaptive Robust Kalman Filter. The result of the trial conducted on the roof of the Nottingham Geospatial Institute (NGI) at the University of Nottingham shows that the integrated solution provides better accuracy and improves the availability of the system in GPS denied environments. RKF can eliminate the effects of gross errors. Additionally, the internal and external reliabilities of the system are enhanced when the UWB observables received from the moving terminals are involved in the positioning algorithm. PMID:27355947

Performance evaluation on cool roofs for green remodeling

NASA Astrophysics Data System (ADS)

Yun, Yosun; Cho, Dongwoo; Cho, Kyungjoo

2018-06-01

Cool roofs refer that maximize heat emission, and minimize the absorption of solar radiation energy, by applying high solar reflectance paints, or materials to roofs or rooftops. The application of cool roofs to existing buildings does not need to take structural issues into consideration, as rooftop greening, is an alternative that can be applied to existing buildings easily. This study installed a cool roofs on existing buildings, and evaluated the performances, using the results to propose certification standards for green remodeling, considering the cool roof-related standards.

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.

Thermal barrier skylight

DOE Office of Scientific and Technical Information (OSTI.GOV)

Couture, P.A.

1984-08-21

The skylight may be of the domed-type or flat-type and of single or double glass (acrylic or other transparent or translucent plastic) construction. The skylight fits within an opening in a roof or the like and has a peripheral base that may be constructed of a metal material such as aluminum, and which is fixed to the roof about the opening. The base comprises inner and outer base frames separated by a thermal break, a peripheral curb frame disposed over the base, and a retainer for securing the skylight cover over the curb frame. The curb frame or support framemore » has inner and outer sections connected by a heat insulating thermal barrier. The curb frame is constructed by welding at the corners of the support frame but eliminating the welding in the area of the thermal barrier thus alleviating a caulking operation at the top and the bottom of the curb frame. The base frame and curb frame have therebetween a compliant sealing means extending contiguously about and overlying the base frame and for sealing between the base frame and support frame.« less

FDP - CENTER FOR ENVIRONMENTAL SCIENCE

EPA Science Inventory

The suite of instruments that supported the research described here, collectively called the “Urban Atmosphere Observatory” (UAO), was located on the roof of the Geophysical Science Building on the campus of the University of Chicago. The following sensors operated at UAO dur...

Hurricane Matthew Damage Survey

NASA Image and Video Library

2016-10-08

Damage to a facility roof is seen during an aerial survey of NASA's Kennedy Space Center in Florida on Saturday. The survey was performed to identify structures and facilities that may have sustained damage from Hurricane Matthew as the storm passed to the east of Kennedy on Oct. 6 and 7, 2016. Officials determined that the center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected. NASA closed the center ahead of the storm’s onset and only a small team of specialists known as the Rideout Team was on the center as the storm approached and passed

Hurricane Matthew Damage Survey

NASA Image and Video Library

2016-10-08

Damage to a facility roof is seen during an aerial survey of NASA's Kennedy Space Center in Florida on Saturday. The survey was performed to identify structures and facilities that may have sustained damage from Hurricane Matthew as the storm passed to the east of Kennedy on Oct. 6 and 7, 2016. Officials determined that the center received some isolated roof damage, damaged support buildings, a few downed power lines, and limited water intrusion. Beach erosion also occurred, although the storm surge was less than expected. NASA closed the center ahead of the storm’s onset and only a small team of specialists known as the Rideout Team was on the center as the storm approached and passed.

34. Roof vent detail from roof of Bwing, looking west ...

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

34. Roof vent detail from roof of B-wing, looking west - Offutt Air Force Base, Strategic Air Command Headquarters & Command Center, Headquarters Building, 901 SAC Boulevard, Bellevue, Sarpy County, NE

A Review of Methods for the Manufacture of Residential Roofing Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akbari, Hashem; Levinson, Ronnen; Berdahl, Paul

2003-06-01

Shingles, tiles, and metal products comprise over 80% (by roof area) of the California roofing market (54-58% fiberglass shingle, 8-10% concrete tile, 8-10% clay tile, 7% metal, 3% wood shake, and 3% slate). In climates with significant demand for cooling energy, increasing roof solar reflectance reduces energy consumption in mechanically cooled buildings, and improves occupant comfort in non-conditioned buildings. This report examines methods for manufacturing fiberglass shingles, concrete tiles, clay tiles, and metal roofing. The report also discusses innovative methods for increasing the solar reflectance of these roofing materials. We have focused on these four roofing products because they aremore » typically colored with pigmented coatings or additives. A better understanding of the current practices for manufacturing colored roofing materials would allow us to develop cool colored materials creatively and more effectively.« less

Water quality function of an extensive vegetated roof.

PubMed

Todorov, Dimitar; Driscoll, Charles T; Todorova, Svetoslava; Montesdeoca, Mario

2018-06-01

In this paper we present the results of a four-year study of water quality in runoff from an extensive, sedum covered, vegetated roof on an urban commercial building. Monitoring commenced seven months after the roof was constructed, with the first growing season. Stormwater drainage quality function of the vegetated roof was compared to a conventional (impermeable, high-albedo) membrane roof in addition to paired measurements of wet and bulk depositions at the study site. We present concentrations and fluxes of nutrients and major solutes. We discuss seasonal and year-to-year variation in water quality of drainage from the vegetated roof and how it compares with atmospheric deposition and drainage from the impermeable roof. Drainage waters from the vegetated roof exhibited a high concentration of nutrients compared to atmospheric deposition, particularly during the warm temperature growing season. However, nutrient losses were generally low because of the strong retention of water by the vegetated roof. There was marked variation in the retention of nutrients by season due to variations in concentrations in drainage from the vegetated roof. The vegetated roof was a sink of nitrogen, total phosphorus and chloride, and a source of phosphate and dissolved inorganic and organic carbon. Chloride exhibited elevated inputs and leaching during the winter. The drainage from the vegetated and impermeable roofs met the United States Environmental Protection Agency freshwater standards for all parameters, except for total phosphorus. Copyright © 2017 Elsevier B.V. All rights reserved.

Roof Type Selection Based on Patch-Based Classification Using Deep Learning for High Resolution Satellite Imagery

NASA Astrophysics Data System (ADS)

Partovi, T.; Fraundorfer, F.; Azimi, S.; Marmanis, D.; Reinartz, P.

2017-05-01

3D building reconstruction from remote sensing image data from satellites is still an active research topic and very valuable for 3D city modelling. The roof model is the most important component to reconstruct the Level of Details 2 (LoD2) for a building in 3D modelling. While the general solution for roof modelling relies on the detailed cues (such as lines, corners and planes) extracted from a Digital Surface Model (DSM), the correct detection of the roof type and its modelling can fail due to low quality of the DSM generated by dense stereo matching. To reduce dependencies of roof modelling on DSMs, the pansharpened satellite images as a rich resource of information are used in addition. In this paper, two strategies are employed for roof type classification. In the first one, building roof types are classified in a state-of-the-art supervised pre-trained convolutional neural network (CNN) framework. In the second strategy, deep features from deep layers of different pre-trained CNN model are extracted and then an RBF kernel using SVM is employed to classify the building roof type. Based on roof complexity of the scene, a roof library including seven types of roofs is defined. A new semi-automatic method is proposed to generate training and test patches of each roof type in the library. Using the pre-trained CNN model does not only decrease the computation time for training significantly but also increases the classification accuracy.

Storm water runoff measurements of copper from a naturally patinated roof and from a parking space. Aspects on environmental fate and chemical speciation.

PubMed

Odnevall Wallinder, I; Hedberg, Y; Dromberg, P

2009-12-01

Release of copper from a naturally aged copper roof on a shopping centre building in a suburban site of Stockholm has been measured during different rain events after its interaction with the internal drainage system and storm drains made of cast iron and concrete. Concentrations of copper removed by means of urban storm water from a nearby parking space have been determined for comparison. Predictions and measurements of the chemical speciation of released copper are discussed compared to the total concentration, and to threshold values for freshwater and drinking water. The results clearly illustrate that the major part of the released copper from the roof is readily retained already during transport through the internal drainage system of the building, a pathway that also changes the chemical speciation of released copper and its bioavailable fraction. Most copper, not retained by cast iron and concrete surfaces, was strongly complexed to organic matter. The median concentration of free cupric ions and weak copper complexes was less than, or within the range of reported no effect concentrations, NOECs, of copper in surface waters. The parking space contributed with significantly higher and time-dependent concentrations of total copper compared to measured concentrations of copper from the roof after the interaction with the drainage system. Most copper in the surface runoff water was strongly complexed with organic matter, hence reducing the bioavailable fraction significantly to concentrations within the NOEC range. Dilution with other sources of urban storm water will reduce the released concentration of copper even further. The results illustrate that already the internal drainage system and the storm drains made of cast iron and concrete act as efficient sinks for released copper which means that any installation of additional infiltration devices is redundant.

Sustainability of rainwater catchment systems for small island communities

NASA Astrophysics Data System (ADS)

Bailey, Ryan T.; Beikmann, Alise; Kottermair, Maria; Taboroši, Danko; Jenson, John W.

2018-02-01

Communities living on atolls and similar low-lying islands in the tropical Pacific rely on rainwater and shallow groundwater to meet domestic water needs. Rainwater, generally captured and stored using rooftop rainwater catchment systems, is the preferred water source due to higher quality and convenience of access. This study assesses the performance of rainwater catchment systems (RWCS) on Ifalik Atoll, located in Yap State, Federated States of Micronesia in the western Pacific. A field survey was conducted in August 2015 to evaluate RWCS features (guttered roof area, storage tank size, gutter leakage conditions), determine numbers of users, and estimate daily water use via household surveys. All 152 RWCS were surveyed. Water balance modeling was applied to the RWCS to estimate end-of-day stored rainwater volumes for each day of the 1997-1999 time period, during which an El Niño-induced drought occurred. Results indicate that the community is resilient to drought, although the majority of RWCS were depleted of rainwater and hence community sharing was required. Scenario testing indicates that increasing guttered roof area is the optimal strategy for enhancing system reliability. For example, the volume of water maintained at the peak of a drought can be tripled if the available roof areas for the RWCS are guttered. Design curves, which provide a set of roof area - tank volume combinations that achieve specified levels of reliability, were created and can be used to plan new RWCS. Besides offering insights into community-wide water storage and usage patterns and resiliency for Ifalik Atoll, this study presents methods that can be applied to other atoll island communities throughout the Indo-Pacific region.

Assessing Cost-effectiveness of Green Infrastructures in response to Large Storm Events at Household Scale

NASA Astrophysics Data System (ADS)

Chui, T. F. M.; Liu, X.; Zhan, W.

2015-12-01

Green infrastructures (GI) are becoming more important for urban stormwater control worldwide. However, relatively few studies focus on researching the specific designs of GI at household scale. This study assesses the hydrological performance and cost-effectiveness of different GI designs, namely green roofs, bioretention systems and porous pavements. It aims to generate generic insights by comparing the optimal designs of each GI in 2-year and 50-year storms of Hong Kong, China and Seattle, US. EPA SWMM is first used to simulate the hydrologic performance, in particular, the peak runoff reduction of thousands of GI designs. Then, life cycle costs of the designs are computed and their effectiveness, in terms of peak runoff reduction percentage per thousand dollars, is compared. The peak runoff reduction increases almost linearly with costs for green roofs. However, for bioretention systems and porous pavements, peak runoff reduction only increases significantly with costs in the mid values. For achieving the same peak runoff reduction percentage, the optimal soil depth of green roofs increases with the design storm, while surface area does not change significantly. On the other hand, for bioretention systems and porous pavements, the optimal surface area increases with the design storm, while thickness does not change significantly. In general, the cost effectiveness of porous pavements is highest, followed by bioretention systems and then green roofs. The cost effectiveness is higher for a smaller storm, and is thus higher for 2-year storm than 50-year storm, and is also higher for Seattle when compared to Hong Kong. This study allows us to better understand the hydrological performance and cost-effectiveness of different GI designs. It facilitates the implementation of optimal choice and design of each specific GI for stormwater mitigation.

75 FR 28632 - Federal Housing Administration (FHA)-Temporary Exemption From Compliance With FHA's Regulation on...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-21

... and balconies, walkways and driveways. iii The roofing, plumbing systems, electrical systems, heating and air conditioning systems; iv. All interiors; and v. All insulation and ventilation systems, as...

Building America Case Study: Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1-1/2 Story Homes in Cold Climates, Minneapolis, MN (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The External Thermal and Moisture Management System (ETMMS), typically seen in deep energy retrofits, is a valuable approach for the roof-only portions of existing homes, particularly the 1 1/2-story home. It is effective in reducing energy loss through the building envelope, improving building durability, reducing ice dams, and providing opportunities to improve occupant comfort and health.

Reducing Heat Gains and Cooling Loads Through Roof Structure Configurations of A House in Medan

NASA Astrophysics Data System (ADS)

Handayani Lubis, Irma; Donny Koerniawan, Mochamad

2018-05-01

Heat gains and heat losses through building surfaces are the main factors that determine the building’s cooling and heating loads. Roof as a building surface that has the most exposed area to the sun, contribute most of heat gains in the building. Therefore, the amount of solar heat gains on the roofs need to be minimized by roof structure configurations. This research aims to discover the optimization of roof structure configurations (coating material, structure material, inclination, overhang, and insulation) as one of passive design strategies that reduce heat gains and cooling loads of a house in Medan. The result showed that case four, white-painted metal roof combined with 45° roof pitched, 1.5m overhang, and addition of insulation, indicates the minimum heat gains production and the less cooling loads during clear sky day but not in the overcast sky condition. In conclusion, heat gains and cooling loads of a house in Medan could be diminished during clear sky day by the addition of roof coating with high reflectance low solar absorbtance, the slope roof, the extension of wider veranda, and the addition of insulation in the roof structure.

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)

TASK 2.5.5 NATURAL EXPOSURE TESTING IN CALIFORNIA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, William A; Cheng, Mengdawn; New, Joshua Ryan

2010-03-01

Airborne particulate matter that settles on a roof can either reflect or absorb incoming solar radiation, dependent on the chemical content and size of the particles. These light scattering and absorption processes occur within a few microns of the surface, and can affect the solar reflectance of the roof. Wilkes et al. (2000) tested 24 different roof coatings on a low-slope test stand and observed about a 25% decrease in the solar reflectance of white-coated and aluminum-coated surfaces as the time of exposure increased; however, the decrease leveled off after 2 years. SPRI Inc. and its affiliates studied the effectmore » of climatic exposure on the surface properties of white thermoplastic single-ply membranes and determined that membranes lose from 30 to 50% of their reflectance over 3 years (Miller et al. 2002). The CMRC and its affiliates AISI, NamZAC, MBMA, MCA and NCCA exposed unpainted and painted metal roofing on both steep- and low-slope test roofs and found that after 3 years, the painted polyvinylidene fluoride (PVDF) metal roofs lost less than 5% of their original reflectance (Miller et al. 2004). The results of the three different weathering studies are very interesting in terms of their solar reflectance after 3 years of exposure. The white thermoplastic membrane and white ceramic coating with white topcoat had original reflectance measures that were about 20 percentage points higher than the painted metal; however, after 3-years of field exposure the solar reflectance of the painted metal exceeds that of the thermoplastic membrane and equals that of the coating. The long-term loss of reflectance appears driven by the ability of the particulate matter to cling to the roof and resist being washed off by wind and or rain. Miller et al. (2002) discovered that aerosol deposition introduced biomass of complex microbial consortia onto the test roofs and the combination of contaminants and biomass accelerated the loss of solar reflectance for the thermoplastic membranes and the roof coatings. Airborne contaminants and biomass were also detected on the painted metal roofs; however, the loss of solar reflectance was less than 5% for the painted metal roofs. The chemistry of the PVDF paint resin system uses similar organic film bonding to that responsible for Teflon , making it extremely chemical resistant and dirt shedding. Miller and Rudolph (2003) found the PVDF painted metals maintained solar reflectance even after 30 years of climatic exposure. Therefore the reduction of roof reflectance is closely related to the composition of the roof and to the chemical profile of the contaminants soiling the roof. Contaminants collected from samples of roof products exposed at seven California weathering sites were analyzed for elements and carbons to characterize the chemical profile of the particles soiling each roof sample and to identify those elements that degrade or enhance solar reflectance. The losses in solar reflectance varied from site to site and also varied at a give site based on the color of the coupon. The least drop in reflectance was observed in the alpine climate of McArthur while the largest drop occurred in sites near urban development. Light color samples were soiled after just one year of exposure. The darker color coupons did not show the same seasonal variations in solar reflectance as observed for the lighter colors. However, after an additional year of exposure the samples at all sites regained most of their solar reflectance due to rain and/or wind washing. The loss of reflectance appears cyclical with the onset of seasons having more rainfall. Solar reflectance of the cool pigmented coupons always exceeded that of the conventional pigmented coupons. Climatic soiling did not cause the cool pigmented roof coupons to lose any more solar reflectance than their conventional pigmented counterparts. The effect of roof slope appears to have more of an effect on lighter color roofs whose solar reflectance exceeds at least 0.5 and visually shows the accumulation of airborne contaminants. The thermal emittance remained invariant with time and location and was therefore not affected by climatic soiling. A thin-film deposition model was developed based on first principles, which simulates light interaction with a soiled substrate. This model was used in combination with the measured data to determine the solar absorptance and reflectance of particulate matter at each of the sites calculated using least squares fitting routines. Principal Component Analysis was used to determine the most important combinations of chemicals correlated with changes in solar absorption. Linear regression helped extract an approximate correlation using chromium, iron and elemental carbon concentrations. It appears that chromium ranks first, iron ranks second, and elemental carbon ranks third in importance to soil absorptance in the data« less

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 rooftop conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Optimizing the position of insulating materials in flat roofs exposed to sunshine to gain minimum heat into buildings under periodic heat transfer conditions.

PubMed

Shaik, Saboor; Talanki, Ashok Babu Puttranga Setty

2016-05-01

Building roofs are responsible for the huge heat gain in buildings. In the present work, an analysis of the influence of insulation location inside a flat roof exposed directly to the sun's radiation was performed to reduce heat gain in buildings. The unsteady thermal response parameters of the building roof such as admittance, transmittance, decrement factor, and time lags have been investigated by solving a one-dimensional diffusion equation under convective periodic boundary conditions. Theoretical results of four types of walls were compared with the experimental results available in literature. The results reveal that the roof with insulation placed at the outer side and at the center plane of the roof is the most energy efficient from the lower decrement factor point of view and the roof with insulation placed at the center plane and the inner side of the roof is the best from the highest time lag point of view among the seven studied configurations. The composite roof with expanded polystyrene insulation located at the outer side and at the center plane of the roof is found to be the best roof from the lowest decrement factor (0.130) point of view, and the composite roof with resin-bonded mineral wool insulation located at the center plane and at the inner side of the roof is found to be energy efficient from the highest time lag point (9.33 h) of view among the seven configurations with five different insulation materials studied. The optimum fabric energy storage thicknesses of reinforced cement concrete, expanded polystyrene, foam glass, rock wool, rice husk, resin-bonded mineral wool, and cement plaster were computed. From the results, it is concluded that rock wool has the least optimum fabric energy storage thickness (0.114 m) among the seven studied building roof materials.

Modelling reduction of urban heat load in Vienna by modifying surface properties of roofs

NASA Astrophysics Data System (ADS)

Žuvela-Aloise, Maja; Andre, Konrad; Schwaiger, Hannes; Bird, David Neil; Gallaun, Heinz

2018-02-01

The study examines the potential of urban roofs to reduce the urban heat island (UHI) effect by changing their reflectivity and implementing vegetation (green roofs) using the example of the City of Vienna. The urban modelling simulations are performed based on high-resolution orography and land use data, climatological observations, surface albedo values from satellite imagery and registry of the green roof potential in Vienna. The modelling results show that a moderate increase in reflectivity of roofs (up to 0.45) reduces the mean summer temperatures in the densely built-up environment by approximately 0.25 °C. Applying high reflectivity materials (roof albedo up to 0.7) leads to average cooling in densely built-up area of approximately 0.5 °C. The green roofs yield a heat load reduction in similar order of magnitude as the high reflectivity materials. However, only 45 % of roof area in Vienna is suitable for greening and the green roof potential mostly applies to industrial areas in city outskirts and is therefore not sufficient for substantial reduction of the UHI effect, particularly in the city centre which has the highest heat load. The strongest cooling effect can be achieved by combining the green roofs with high reflectivity materials. In this case, using 50 or 100 % of the green roof potential and applying high reflectivity materials on the remaining surfaces have a similar cooling effect.

Quantitative analysis and paleoecology of the Secor Coal and roof-shale floras (middle Pennsylvania, Oklahoma)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dimichele, W.A.; McBrinn, G.E.; Phillips, T.L.

1991-08-01

The Secor Coal of Oklahoma (Boggy Formation, lower Desmoinesian/Westphalian D equivalent) is one of the few coals discovered, to date, in which Anabathra pulcherrima (=Paralycopodites brevifolius) was a dominant element. Anabathra and Lepidophloios define the major assemblages in the coal, which also contains elements of medullosan pteridosperms and Cardiocarpus spinatus producing cordaites. The Lepidophloios to Medullosa gradient is not obscured by the numerous Anabathra-dominated zones, and a disturbance element is suggested in association with Anabathra abundance. Comparison of the coal-ball flora with a clastic-compression flora from the roof of the coal reveals widely divergent patterns of dominance and diversity. Themore » compression flora is strongly dominated by medullosan pteridosperms with subdominant marattialean tree ferns. As in most instances, the compression flora from the immediate roof of the coal is not an accurate representation of the peat-forming vegetation, at either the level of species composition or the relative abundance of major groups of plants. The swamp and surrounding clastic deltaic environments were edaphically distinct and supported separate floras between which there was limited species exchange.« less

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

Code of Federal Regulations, 2011 CFR

2011-07-01

... pitch, asphalt prepared paper, tile, composite roofing materials, slate, metal, translucent materials, and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

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, and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

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, and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

GREENROOF RUNOFF WATER QUALITY

EPA Science Inventory

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

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ueno, K.; Lstiburek, J. W.

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.more » 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.« less

'Passive-roof' duplex geometry in the frontal structures of the Kirthar and Sulaiman mountain belts, Pakistan

NASA Astrophysics Data System (ADS)

Banks, C. J.; Warburton, J.

Exploration for hydrocarbons over the past few years has greatly improved our understanding of the geometry of frontal mountain belt structures. In this study we introduce and discuss the concept of the 'Passive-roof duplex', using as the main example the Kirthar and Sulaiman Ranges in the Baluchistan Province of Pakistan. Structures similar to those described here have been recognized previously in other mountain belts, and they appear to exist as a common feature in many more frontal regions of mountain belts. Our example of a Passive-roof duplex which we describe from Pakistan is compared briefly with similar structures reported by others. The Passive-roof duplex is here defined as a duplex whose roof thrust has backthrust sense ( Passive-roof thrust) and whose roof sequence (those rocks lying above the roof thrust) remains relatively 'stationary' during foreland directed piggy-back style propagation of horses within the duplex.

The Mobile Advanced Command and Control Station (MACCS) Experimental Testbed

DTIC Science & Technology

2007-10-01

were selected: Vehicle: Dodge (Sprinter 2500 high-roof - Mercedes - Benz vehicle) Electrical equipment and habitability equipment: Crossroads Coaches...this innovative , mobile, experimental tested. IMPACT/APPLICATIONS While MACCS clearly supports the research agenda for both HAL and ONR (as well as

Photocopy of photograph (digital image located in LBNL Photo Lab ...

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

Photocopy of photograph (digital image located in LBNL Photo Lab Collection, XBD200503-00117-046). March 2005. ROOF SHIELDING BLOCK AND I-BEAM SUPPORT CONSTRUCTION, CENTER OF BEVATRON - University of California Radiation Laboratory, Bevatron, 1 Cyclotron Road, Berkeley, Alameda County, CA