The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
William M. Mcginley - One of the best experts on this subject based on the ideXlab platform.
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performance of clay masonry veneer in Wood Stud walls subjected to out of plane seismic loads
Earthquake Engineering & Structural Dynamics, 2010Co-Authors: Hussein Okail, Richard E. Klingner, Benson P Shing, William M. McginleyAbstract:This paper presents the findings of shaking-table experiments conducted to examine the out-of-plane seismic performance of masonry veneer walls. Seven wall assemblies were tested, each consisting of a clay masonry veneer anchored to a Wood-Stud backing. Design variables include the type of veneer ties, tie spacing, and presence or absence of mortar joint reinforcement and window opening. The walls were designed and constructed in accordance with current US code provisions. Results of the experiments show that failure of the corrugated ties is governed by pullout of the nails from the Wood Studs, while failure of the rigid ties is governed by detachment from the mortar joints or pull-through of the screw heads through fastener holes. Both types of ties show satisfactory performance under ground motions corresponding to Design Basis and Maximum Considered Earthquakes representative of Seismic Design Category E. Although the rigid ties were stronger than the corrugated ties, they had wider vertical spacing and failed at a slightly higher seismic load. Observed extraction capacities of the nails show high variability, which merits attention. Joint reinforcement did not show any noticeable effect on the out-of-plane behavior of the veneer. Results of an analytical Study have shown that the detachment of a veneer from the backing system is preceded by veneer cracking, which influences the distribution of tie forces, and that the vertical tie spacing influences the cracking load tor the veneer.
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Performance of clay masonry veneer in Wood‐Stud walls subjected to out‐of‐plane seismic loads
Earthquake Engineering & Structural Dynamics, 2010Co-Authors: Hussein Okail, P. Benson Shing, Richard E. Klingner, William M. McginleyAbstract:This paper presents the findings of shaking-table experiments conducted to examine the out-of-plane seismic performance of masonry veneer walls. Seven wall assemblies were tested, each consisting of a clay masonry veneer anchored to a Wood-Stud backing. Design variables include the type of veneer ties, tie spacing, and presence or absence of mortar joint reinforcement and window opening. The walls were designed and constructed in accordance with current US code provisions. Results of the experiments show that failure of the corrugated ties is governed by pullout of the nails from the Wood Studs, while failure of the rigid ties is governed by detachment from the mortar joints or pull-through of the screw heads through fastener holes. Both types of ties show satisfactory performance under ground motions corresponding to Design Basis and Maximum Considered Earthquakes representative of Seismic Design Category E. Although the rigid ties were stronger than the corrugated ties, they had wider vertical spacing and failed at a slightly higher seismic load. Observed extraction capacities of the nails show high variability, which merits attention. Joint reinforcement did not show any noticeable effect on the out-of-plane behavior of the veneer. Results of an analytical Study have shown that the detachment of a veneer from the backing system is preceded by veneer cracking, which influences the distribution of tie forces, and that the vertical tie spacing influences the cracking load tor the veneer.
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Shaking‐table tests of a full‐scale single‐story masonry veneer Wood‐frame structure
Earthquake Engineering & Structural Dynamics, 2010Co-Authors: Hussein Okail, William M. Mcginley, P. Benson Shing, Richard E. Klingner, David I. McleanAbstract:This paper presents the findings of shaking-table experiments conducted to examine the seismic performance of a full-scale, one-story, Wood-framed structure with masonry veneer. The structure was designed and constructed in accordance with current U.S. code provisions. The veneer was attached to the Wood backing with two kinds of metal anchors, corrugated ties fastened with 8d nails and rigid ties fastened with #8 screws. The tests have shown that the use of nails to fasten veneer anchors to the Wood Studs is highly unreliable due to the high variation of the nail extraction capacity, which can be influenced by the moisture content of the Wood. Other than this, both the Wood frame and the masonry veneer performed well under severe ground motions far exceeding a design level earthquake for Seismic Design Category D. Good performance was observed for the rigid veneer ties, which were attached to the Wood Studs with screws. The results have shown that the veneer walls parallel to the direction of shaking helped to restrain the motion of the Wood structure and therefore should not be simply treated as added mass. The detailing of Wood roof diaphragms requires special attention in consideration of the out-of-plane inertia force of the veneer that can be transmitted through the top plate of the Wood-Stud wall to the rim joist. Copyright © 2010 John Wiley & Sons, Ltd.
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Seismic Performance Tests of Masonry and Masonry Veneer
Journal of ASTM International, 2010Co-Authors: Richard E. Klingner, William M. Mcginley, P. Shing, David I. Mclean, Hussein OkailAbstract:This paper summarizes the preliminary findings of a research project on performance-based design of masonry and masonry veneer. The project includes quasi-static testing of clay masonry veneer with Wood-Stud and concrete masonry backings; shaking-table tests of concrete masonry and Wood-Stud wall segments with clay masonry veneer; and shaking-table tests of a full-scale Wood-Stud structure with clay masonry veneer and a concrete masonry structure with clay masonry veneer; and nonlinear analytical modeling. Based on the test results, recommendations are presented for refinements to current seismic design and detailing provisions for masonry and masonry veneer.
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Seismic Masonry Veneer: Quazi- Static Testing of Wood Stud Backed Clay Masonry Veneer Walls
Structures Congress 2008, 2008Co-Authors: William M. Mcginley, Sameer HamoushAbstract:Based on past performance during seismic events, masonry veneers can pose a significant hazard to public safety. Because there is a significant inventory of masonry veneers in the built environment, this risk is substantial and must be quantified and systematically mitigated. In addition, current design provisions must be re-evaluated and refined to ensure that new building construction produces masonry wall assemblies with acceptable seismic performance. To address these concerns a number of researchers have investigated this type of wall system under seismic loading. To extend this work further, an effort is being funded under the George E. Brown Network for Earthquake Engineering Simulation to evaluate the response of masonry veneer systems under seismic loading. One of the goals of this investigation is to develop accurate dynamic wall system models for seismic excitation. These models are to be used to support development of performance based design under frameworks such as those proposed by ATC 58. As a part of this multi-institutional investigation, the performance of clay brick veneer walls constructed with Wood Stud backing walls are being experimentally evaluated. This phase of the testing program subjected full scale brick veneer/Wood Stud wall specimens constructed to typical code defined residential configurations to quasi-static cyclic in-plane and out-of-plane loadings. A variety of wall specimen configurations are being evaluated, including variables such as the effects of joint reinforcing, the type and spacing of ties, and the effects of openings. The result of these tests will refine the analytical models being developed and support the development of large scale shake table building specimens that will be evaluated at a later date. The results of the quasi-static out-of-plane loading tests are presented in this paper. The following sections describe the details of the testing program.
Hussein Okail - One of the best experts on this subject based on the ideXlab platform.
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Seismic Performance of Low-Rise Wood-Framed and Reinforced Masonry Buildings with Clay Masonry Veneer
Journal of Structural Engineering, 2013Co-Authors: Richard E. Klingner, P. Benson Shing, David I. Mclean, W. Mark Mcginley, Hussein OkailAbstract:AbstractThis paper describes a coordinated experimental and analytical Study that investigated the seismic performance of Wood-Stud construction with clay masonry veneer and of RC masonry construction with clay masonry veneer designed according to current U.S. building codes. As part of this Study, two 1-story buildings were tested on a shaking table. Both had clay veneer on the outside. One had Wood-frame walls for the backing and load-resisting system, whereas the other had RC masonry walls. With one exception, the behavior of the veneer in the Wood-framed building was satisfactory up to levels of shaking consistent with the design level earthquake. That exception was related to the relatively low pullout strength in wet Wood of the conventional nails used to attach the veneer connectors to the Wood-Stud wall. On the basis of this Study, code changes have been implemented to require the use of higher-capacity fasteners for such applications. The Wood-frame building specimen itself did not collapse under...
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performance of clay masonry veneer in Wood Stud walls subjected to out of plane seismic loads
Earthquake Engineering & Structural Dynamics, 2010Co-Authors: Hussein Okail, Richard E. Klingner, Benson P Shing, William M. McginleyAbstract:This paper presents the findings of shaking-table experiments conducted to examine the out-of-plane seismic performance of masonry veneer walls. Seven wall assemblies were tested, each consisting of a clay masonry veneer anchored to a Wood-Stud backing. Design variables include the type of veneer ties, tie spacing, and presence or absence of mortar joint reinforcement and window opening. The walls were designed and constructed in accordance with current US code provisions. Results of the experiments show that failure of the corrugated ties is governed by pullout of the nails from the Wood Studs, while failure of the rigid ties is governed by detachment from the mortar joints or pull-through of the screw heads through fastener holes. Both types of ties show satisfactory performance under ground motions corresponding to Design Basis and Maximum Considered Earthquakes representative of Seismic Design Category E. Although the rigid ties were stronger than the corrugated ties, they had wider vertical spacing and failed at a slightly higher seismic load. Observed extraction capacities of the nails show high variability, which merits attention. Joint reinforcement did not show any noticeable effect on the out-of-plane behavior of the veneer. Results of an analytical Study have shown that the detachment of a veneer from the backing system is preceded by veneer cracking, which influences the distribution of tie forces, and that the vertical tie spacing influences the cracking load tor the veneer.
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Performance of clay masonry veneer in Wood‐Stud walls subjected to out‐of‐plane seismic loads
Earthquake Engineering & Structural Dynamics, 2010Co-Authors: Hussein Okail, P. Benson Shing, Richard E. Klingner, William M. McginleyAbstract:This paper presents the findings of shaking-table experiments conducted to examine the out-of-plane seismic performance of masonry veneer walls. Seven wall assemblies were tested, each consisting of a clay masonry veneer anchored to a Wood-Stud backing. Design variables include the type of veneer ties, tie spacing, and presence or absence of mortar joint reinforcement and window opening. The walls were designed and constructed in accordance with current US code provisions. Results of the experiments show that failure of the corrugated ties is governed by pullout of the nails from the Wood Studs, while failure of the rigid ties is governed by detachment from the mortar joints or pull-through of the screw heads through fastener holes. Both types of ties show satisfactory performance under ground motions corresponding to Design Basis and Maximum Considered Earthquakes representative of Seismic Design Category E. Although the rigid ties were stronger than the corrugated ties, they had wider vertical spacing and failed at a slightly higher seismic load. Observed extraction capacities of the nails show high variability, which merits attention. Joint reinforcement did not show any noticeable effect on the out-of-plane behavior of the veneer. Results of an analytical Study have shown that the detachment of a veneer from the backing system is preceded by veneer cracking, which influences the distribution of tie forces, and that the vertical tie spacing influences the cracking load tor the veneer.
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Shaking‐table tests of a full‐scale single‐story masonry veneer Wood‐frame structure
Earthquake Engineering & Structural Dynamics, 2010Co-Authors: Hussein Okail, William M. Mcginley, P. Benson Shing, Richard E. Klingner, David I. McleanAbstract:This paper presents the findings of shaking-table experiments conducted to examine the seismic performance of a full-scale, one-story, Wood-framed structure with masonry veneer. The structure was designed and constructed in accordance with current U.S. code provisions. The veneer was attached to the Wood backing with two kinds of metal anchors, corrugated ties fastened with 8d nails and rigid ties fastened with #8 screws. The tests have shown that the use of nails to fasten veneer anchors to the Wood Studs is highly unreliable due to the high variation of the nail extraction capacity, which can be influenced by the moisture content of the Wood. Other than this, both the Wood frame and the masonry veneer performed well under severe ground motions far exceeding a design level earthquake for Seismic Design Category D. Good performance was observed for the rigid veneer ties, which were attached to the Wood Studs with screws. The results have shown that the veneer walls parallel to the direction of shaking helped to restrain the motion of the Wood structure and therefore should not be simply treated as added mass. The detailing of Wood roof diaphragms requires special attention in consideration of the out-of-plane inertia force of the veneer that can be transmitted through the top plate of the Wood-Stud wall to the rim joist. Copyright © 2010 John Wiley & Sons, Ltd.
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Seismic Performance Tests of Masonry and Masonry Veneer
Journal of ASTM International, 2010Co-Authors: Richard E. Klingner, William M. Mcginley, P. Shing, David I. Mclean, Hussein OkailAbstract:This paper summarizes the preliminary findings of a research project on performance-based design of masonry and masonry veneer. The project includes quasi-static testing of clay masonry veneer with Wood-Stud and concrete masonry backings; shaking-table tests of concrete masonry and Wood-Stud wall segments with clay masonry veneer; and shaking-table tests of a full-scale Wood-Stud structure with clay masonry veneer and a concrete masonry structure with clay masonry veneer; and nonlinear analytical modeling. Based on the test results, recommendations are presented for refinements to current seismic design and detailing provisions for masonry and masonry veneer.
David V. Rosowsky - One of the best experts on this subject based on the ideXlab platform.
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Reliability of Light-Frame Wall Systems Subject to Combined Axial and Transverse Loads
Journal of Structural Engineering-asce, 2005Co-Authors: David V. Rosowsky, Guangren Yu, William M. BulleitAbstract:Wood frame walls are essential subassemblies used to transmit roof, floor, wind, and seismic loads into lower stories and eventually into the foundation of light-frame structures. There has been some discussion and debate in recent years over appropriate system factors for use in the design of repetitive wall members, which typically are much smaller in the cross section than floor joists. In addition to having greater flexibility than floors, Wood Stud walls also may be subject to the actions of combined loads, and their load-sharing behavior may be significantly influenced by the presence of openings. As a precursor to evaluating system factors for design, this Study investigated load-sharing and system effects in light-frame walls subject to combined axial and transverse loads. An analytical model was developed to account for partial composite action, load-sharing, two-way action, and openings in the wall system. The model consisted of two main components: A system model and a member model. The system ...
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modeling Wood walls subjected to combined transverse and axial loads
Journal of Structural Engineering-asce, 2005Co-Authors: William M. Bulleit, Weichiang Pang, David V. RosowskyAbstract:Repetitive-member wall systems are among the most essential structural systems in conventional light-frame construction. Wood Stud walls serve a variety of structural functions, particularly in regions of high natural-hazard risk, carrying axial forces, in-plane shear forces, and out-of-plane forces. This paper describes a structural analysis model for Wood walls under transverse wind loads combined with either axial tension from wind uplift or axial compression from snow and live load suitable for reliability Studies. The average model results compared well to available wall test data. Monte Carlo simulation was used in sensitivity Studies of the transverse ramp-load behavior of walls under various levels of axial load. These simulations show that the model captures the range of possible behaviors of Stud walls under various levels of axial load, both compression and tension. The model is accurate and simple enough to be used in reliability analyses, which will be described in a later paper.
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PARTIAL FACTOR APPROACH TO REPETITIVE-MEMBER SYSTEM FACTORS
Journal of Structural Engineering, 2004Co-Authors: David V. RosowskyAbstract:Beneficial system behavior has been acknowledged in the design of repetitive-member systems. Current design specifications for Wood (both National Design Specification and LRFD) permit the use of a repetitive-member factor to account for load-sharing or redistribution of load between framing members and partial composite action. The factors, however, were developed based on a simple statistical model rather than a more rigorous or comprehensive analytical Study. The paper reports on a Study to investigate load-sharing and system effects in light-frame wall systems and evaluate system factors for codified design that rationally account for load sharing and other system behavior. An objective at the Study was to develop system factors that could be used in the design of individual wall members, much as repetitive member factors are used in the design of parallel-member floor and roof systems. Wall Studs typically are much smaller in cross section than floor joists. In addition to having greater flexibility than floors, Wood Stud walls may be subject to the actions of combined loads and their load-sharing behavior may be influenced significantly by the presence of openings. A single system factor may, in fact, not be adequate to account for a wide range of system configurations, loading types, and so forth. This paper presents a new framework based on partial system factors to account for different system effects in parallel-member Wood systems.
William M. Bulleit - One of the best experts on this subject based on the ideXlab platform.
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Reliability of Light-Frame Wall Systems Subject to Combined Axial and Transverse Loads
Journal of Structural Engineering-asce, 2005Co-Authors: David V. Rosowsky, Guangren Yu, William M. BulleitAbstract:Wood frame walls are essential subassemblies used to transmit roof, floor, wind, and seismic loads into lower stories and eventually into the foundation of light-frame structures. There has been some discussion and debate in recent years over appropriate system factors for use in the design of repetitive wall members, which typically are much smaller in the cross section than floor joists. In addition to having greater flexibility than floors, Wood Stud walls also may be subject to the actions of combined loads, and their load-sharing behavior may be significantly influenced by the presence of openings. As a precursor to evaluating system factors for design, this Study investigated load-sharing and system effects in light-frame walls subject to combined axial and transverse loads. An analytical model was developed to account for partial composite action, load-sharing, two-way action, and openings in the wall system. The model consisted of two main components: A system model and a member model. The system ...
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modeling Wood walls subjected to combined transverse and axial loads
Journal of Structural Engineering-asce, 2005Co-Authors: William M. Bulleit, Weichiang Pang, David V. RosowskyAbstract:Repetitive-member wall systems are among the most essential structural systems in conventional light-frame construction. Wood Stud walls serve a variety of structural functions, particularly in regions of high natural-hazard risk, carrying axial forces, in-plane shear forces, and out-of-plane forces. This paper describes a structural analysis model for Wood walls under transverse wind loads combined with either axial tension from wind uplift or axial compression from snow and live load suitable for reliability Studies. The average model results compared well to available wall test data. Monte Carlo simulation was used in sensitivity Studies of the transverse ramp-load behavior of walls under various levels of axial load. These simulations show that the model captures the range of possible behaviors of Stud walls under various levels of axial load, both compression and tension. The model is accurate and simple enough to be used in reliability analyses, which will be described in a later paper.
Mohamed A. Sultan - One of the best experts on this subject based on the ideXlab platform.
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Temperature Measurements in Full-Scale Wood Stud Shear Walls
2003Co-Authors: Denham, Venkatesh Kodur, Mohamed A. Sultan, E. M. A. DenhamAbstract:This report presents the results of 10 full-scale fire resistance tests conducted at the National Fire Laboratory on load-bearing gypsum board protected, Wood Stud shear wall assemblies with and without resilient channels on the fire-exposed side. The two assembly arrangements Studied were: symmetrical installation 1x1 (one layer of gypsum board on each of the exposed and unexposed sides) and asymmetrical installation of the shear membrane (one layer of gypsum board on both the exposed and unexposed sides and a shear wall membrane as a base layer alternating between the exposed (2x1) and unexposed sides (1x2)) on a Wood Stud frame. The gypsum board was 12.7 mm thick Type X. The insulations used were glass and rock fibres. The shear membranes used were plyWood and oriented strand board (OSB). Tests were conducted to determine the effects of the placement of the shear membrane on the exposed/unexposed face, type of shear membrane, insulation type, load intensity and resilient channel installations on the fire resistance of gypsum board protected, Wood Stud shear wall assemblies. Details of the results, including the temperatures and deflections measured during the fire tests, are presented. TEMPERATURE MEASUREMENTS IN FULL-SCALE Wood Stud SHEAR WALLS
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Experimental Study and numerical modelling of the fire resistance of Wood-Stud wall assemblies
2002Co-Authors: Noureddine Bénichou, Venkatesh Kodur, Mohamed A. SultanAbstract:ABSTRACT : This paper presents the results from an experimental Study on the behaviour of gypsumboard protected, Wood-Stud shear wall assemblies. The experimental Study consisted of fire resistancetests on 12 full-scale wall assemblies. The factors investigated included effects of placement and type ofshear membrane, insulation type, presence of resilient channels and load intensity on the fire resistanceof such assemblies. The test results show that the shear membrane placement and insulation type,significantly influence the fire resistance of Wood-Stud shear walls. The results of this and other Studieswere used to develop a model for predicting the fire resistance of Wood-Stud wall assemblies. The modelcouples a heat transfer sub-model and a structural sub-model. The heat transfer sub-model predicts thetemperature profile inside the Wood-Stud assembly and the time to insulation failure. The structural sub-model uses the temperature profile to calculate the deflection of the Studs and the time to structural failureof the assembly. A comparison with test results indicates that the model predictions are reasonable.
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Performance of Wood Stud shear walls exposed to fire
Fire and Materials, 2000Co-Authors: Venkatesh Kodur, Mohamed A. SultanAbstract:This paper presents the results of seven full-scale fire resistance tests conducted on load-bearing gypsum board protected, Wood Stud shear wall assemblies. The experimental Studies were conducted to determine the effects of placement of shear membrane and type of insulation on the fire resistance of such assemblies. Details of the results, including the temperatures and deflections measured during the fire tests, are presented. Results from the Studies indicate that the placement of shear membrane and insulation type significantly influence the fire resistance of such Wood Stud shear wall assemblies.
