Documents disponibles écrits par cet auteur

Estimating natural periods of steel plate shear wall frames / Shi Liu in Journal of structural engineering, Vol. 139 N° 1 (Janvier 2013) 

Public ISBD [article]  in Journal of structural engineering > Vol. 139 N° 1 (Janvier 2013) . - pp. 155–161 Titre : Estimating natural periods of steel plate shear wall frames Type de document : texte imprimé Auteurs : Shi Liu, Auteur ; Gordon P. Warn, Auteur ; Jeffrey W. Berman, Auteur Année de publication : 2013 Article en page(s) : pp. 155–161 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Steel  plate  shear  walls  Natural  periods  Approximate  method Résumé : A steel plate shear wall (SPSW) with thin, unstiffened web plates is one type of seismic lateral force–resisting system that is gaining popularity. SPSWs are used in low to midrise building construction typically with two or more frames in each orthogonal direction to resist seismic loading combined with gravity framing. The SPSWs therefore control the lateral force response of the building and the building’s natural periods of vibration. For design of any seismic load–resisting system, an estimation of the building’s first-mode period is necessary to calculate seismic loads and estimate resulting frame drift. This paper presents a method for estimating the first three natural periods of a SPSW with nonuniform properties along its height, accounting for both shear and flexural deformations of the system. The proposed method approximates the SPSW frame as shear and flexural systems separately to determine corresponding frequencies and then combines these frequencies using Dunkerley’s equation. A comparison of periods estimated using the approximate method with those obtained from modal analysis of detailed finite-element models suggests that the proposed method is appropriate for estimating the first-mode period of SPSW frames. The proposed method could be valuable for refining the seismic design of these frames or for verifying the results of large, complex steel plate shear wall building models. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000610 [article] Estimating natural periods of steel plate shear wall frames [texte imprimé] / Shi Liu, Auteur ; Gordon P. Warn, Auteur ; Jeffrey W. Berman, Auteur . - 2013 . - pp. 155–161. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 139 N° 1 (Janvier 2013) . - pp. 155–161 Mots-clés : Steel  plate  shear  walls  Natural  periods  Approximate  method Résumé : A steel plate shear wall (SPSW) with thin, unstiffened web plates is one type of seismic lateral force–resisting system that is gaining popularity. SPSWs are used in low to midrise building construction typically with two or more frames in each orthogonal direction to resist seismic loading combined with gravity framing. The SPSWs therefore control the lateral force response of the building and the building’s natural periods of vibration. For design of any seismic load–resisting system, an estimation of the building’s first-mode period is necessary to calculate seismic loads and estimate resulting frame drift. This paper presents a method for estimating the first three natural periods of a SPSW with nonuniform properties along its height, accounting for both shear and flexural deformations of the system. The proposed method approximates the SPSW frame as shear and flexural systems separately to determine corresponding frequencies and then combines these frequencies using Dunkerley’s equation. A comparison of periods estimated using the approximate method with those obtained from modal analysis of detailed finite-element models suggests that the proposed method is appropriate for estimating the first-mode period of SPSW frames. The proposed method could be valuable for refining the seismic design of these frames or for verifying the results of large, complex steel plate shear wall building models. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000610

Experimental investigation of self-centering steel plate shear walls / Patricia M. Clayton in Journal of structural engineering, Vol. 138 N° 7 (Juillet 2012) 

Public ISBD [article]  in Journal of structural engineering > Vol. 138 N° 7 (Juillet 2012) . - pp. 952–960 Titre : Experimental investigation of self-centering steel plate shear walls Type de document : texte imprimé Auteurs : Patricia M. Clayton, Auteur ; Tyler B. Winkley, Auteur ; Jeffrey W. Berman, Auteur Année de publication : 2012 Article en page(s) : pp. 952–960 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Self-centering  Rocking  connection  Steel  plate  Shear  wall  Experimentation Résumé : A series of subassembly tests were conducted to investigate the behavior of the self-centering steel plate shear wall (SC-SPSW) system under cyclic loading. The SC-SPSW system utilizes thin steel web plates to provide energy dissipation and the primary strength and stiffness of the system, whereas posttensioned (PT) beam-to-column connections provide recentering capabilities. In this new system, the web plate is intended to yield under cyclic loading, whereas the boundary elements and PT connection elements remain undamaged. The web plate can then be replaced relatively easily following significant inelastic cycles. This experimental program studies the effects of various design parameters on the system and connection response and compares the response with approximate analytical formulas. The experimental results show that the SC-SPSW system has high ductility, high initial stiffness, recentering capabilities, an overall system response as anticipated, and more energy dissipation than expected. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000531 [article] Experimental investigation of self-centering steel plate shear walls [texte imprimé] / Patricia M. Clayton, Auteur ; Tyler B. Winkley, Auteur ; Jeffrey W. Berman, Auteur . - 2012 . - pp. 952–960. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 138 N° 7 (Juillet 2012) . - pp. 952–960 Mots-clés : Self-centering  Rocking  connection  Steel  plate  Shear  wall  Experimentation Résumé : A series of subassembly tests were conducted to investigate the behavior of the self-centering steel plate shear wall (SC-SPSW) system under cyclic loading. The SC-SPSW system utilizes thin steel web plates to provide energy dissipation and the primary strength and stiffness of the system, whereas posttensioned (PT) beam-to-column connections provide recentering capabilities. In this new system, the web plate is intended to yield under cyclic loading, whereas the boundary elements and PT connection elements remain undamaged. The web plate can then be replaced relatively easily following significant inelastic cycles. This experimental program studies the effects of various design parameters on the system and connection response and compares the response with approximate analytical formulas. The experimental results show that the SC-SPSW system has high ductility, high initial stiffness, recentering capabilities, an overall system response as anticipated, and more energy dissipation than expected. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000531

Reduced link sections for improving the ductility of eccentrically braced frame link-to-column connections / Jeffrey W. Berman in Journal of structural engineering, Vol. 136 N° 5 (Mai 2010) 

Public ISBD [article]  in Journal of structural engineering > Vol. 136 N° 5 (Mai 2010) . - pp. 543-553 Titre : Reduced link sections for improving the ductility of eccentrically braced frame link-to-column connections Type de document : texte imprimé Auteurs : Jeffrey W. Berman, Auteur ; Taichiro Okazaki, Auteur ; Heidrun O. Hauksdottir, Auteur Année de publication : 2011 Article en page(s) : pp. 543-553 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Eccentrically  braced  frames  Reduced  beam  sections  Finite-element  analysis  Link-to-column  connections  Ductility  Steel  frames Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Eccentrically braced frames (EBFs) are desirable seismic load resisting systems as they combine the high elastic stiffness of concentrically braced frames with the ductility and stable energy dissipation of moment resisting frames. EBFs with links attached to the columns are particularly appealing for architectural flexibility as they provide multiple locations for placement of doors and hallways. However, previous research has shown that link-to-column connections are prone to failure at low drift levels, due to their susceptibility to fracture at the link flange-to-column welds. This paper investigates the application of the reduced beam section concept for links in eccentrically braced frames to enhance the ductility of link-to-column connections. A design procedure for link section reduction is proposed and preliminary finite-element analyses are conducted on a shear link with various reduced section geometries. A parametric study performed on an array of links having various cross sections and lengths suggests that the reduced link section may substantially reduce the plastic flange strains at the link ends, which can improve the fracture life. The reduction in plastic flange strains is found to be significant for all links, with larger reductions for intermediate and flexural links. Furthermore, the detrimental kinking deformation of the flanges, caused by the large rotation demands in shear links, is moved away from the column face when reduced sections were used. While the analysis results show promise, experimental verification is recommended before the proposed design procedure can be implemented in practice. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i5/p543_s1?isAuthorized=no [article] Reduced link sections for improving the ductility of eccentrically braced frame link-to-column connections [texte imprimé] / Jeffrey W. Berman, Auteur ; Taichiro Okazaki, Auteur ; Heidrun O. Hauksdottir, Auteur . - 2011 . - pp. 543-553. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 5 (Mai 2010) . - pp. 543-553 Mots-clés : Eccentrically  braced  frames  Reduced  beam  sections  Finite-element  analysis  Link-to-column  connections  Ductility  Steel  frames Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Eccentrically braced frames (EBFs) are desirable seismic load resisting systems as they combine the high elastic stiffness of concentrically braced frames with the ductility and stable energy dissipation of moment resisting frames. EBFs with links attached to the columns are particularly appealing for architectural flexibility as they provide multiple locations for placement of doors and hallways. However, previous research has shown that link-to-column connections are prone to failure at low drift levels, due to their susceptibility to fracture at the link flange-to-column welds. This paper investigates the application of the reduced beam section concept for links in eccentrically braced frames to enhance the ductility of link-to-column connections. A design procedure for link section reduction is proposed and preliminary finite-element analyses are conducted on a shear link with various reduced section geometries. A parametric study performed on an array of links having various cross sections and lengths suggests that the reduced link section may substantially reduce the plastic flange strains at the link ends, which can improve the fracture life. The reduction in plastic flange strains is found to be significant for all links, with larger reductions for intermediate and flexural links. Furthermore, the detrimental kinking deformation of the flanges, caused by the large rotation demands in shear links, is moved away from the column face when reduced sections were used. While the analysis results show promise, experimental verification is recommended before the proposed design procedure can be implemented in practice. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i5/p543_s1?isAuthorized=no

Seismic design and performance of self-centering steel plate shear walls / Patricia M. Clayton in Journal of structural engineering, Vol. 138 N° 1 (Janvier 2012) 

Public ISBD [article]  in Journal of structural engineering > Vol. 138 N° 1 (Janvier 2012) . - pp. 22-30 Titre : Seismic design and performance of self-centering steel plate shear walls Type de document : texte imprimé Auteurs : Patricia M. Clayton, Auteur ; Jeffrey W. Berman, Auteur ; Laura N. Lowes, Auteur Année de publication : 2012 Article en page(s) : pp. 22-30 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Self-centering  Rocking  connection  Steel  plate  Shear  wall  Seismic  design  Nonlinear  response  history  analysis Résumé : The self-centering steel plate shear wall (SC-SPSW) is a new seismic load-resisting system that combines the strength and stiffness properties of the SPSW with the recentering capabilities of posttensioned (PT) beam-to-column connections. This paper outlines a proposed seismic design procedure aimed at achieving specified structural performance targets and analytical methods for modeling such a system. A series of 3-and 9-story prototype buildings located in a high seismic zone in California was designed using the procedure, and nonlinear, dynamic analyses were performed for these prototype buildings using ground motions representing three seismic hazard levels. The analysis results show that the systems achieved the desired performance objectives, including recentering of the lateral system. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v138/i1/p22_s1?isAuthorized=no [article] Seismic design and performance of self-centering steel plate shear walls [texte imprimé] / Patricia M. Clayton, Auteur ; Jeffrey W. Berman, Auteur ; Laura N. Lowes, Auteur . - 2012 . - pp. 22-30. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 138 N° 1 (Janvier 2012) . - pp. 22-30 Mots-clés : Self-centering  Rocking  connection  Steel  plate  Shear  wall  Seismic  design  Nonlinear  response  history  analysis Résumé : The self-centering steel plate shear wall (SC-SPSW) is a new seismic load-resisting system that combines the strength and stiffness properties of the SPSW with the recentering capabilities of posttensioned (PT) beam-to-column connections. This paper outlines a proposed seismic design procedure aimed at achieving specified structural performance targets and analytical methods for modeling such a system. A series of 3-and 9-story prototype buildings located in a high seismic zone in California was designed using the procedure, and nonlinear, dynamic analyses were performed for these prototype buildings using ground motions representing three seismic hazard levels. The analysis results show that the systems achieved the desired performance objectives, including recentering of the lateral system. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v138/i1/p22_s1?isAuthorized=no