Effects of Partially Restrained Connection Stiffness and Strength on Frame Seismic Performance PDF Download

Author: Bruce F. Maison
Publisher:
ISBN:
Category : Building, Iron and steel
Languages : en
Pages : 148

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Author: Mathias A. Kozma Thomas
Publisher:
ISBN:
Category :
Languages : en
Pages : 280

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Book Description
Hybrid steel moment-resting frames are a relatively new concept founded on a combination of ordinary, intermediate, and special moment frames within the same lateral force resisting system. The intent of hybrid frames is to improve seismic performance by attaining better control of the hinging sequence, thus maximizing energy dissipation while delaying loss of stiffness. This study focuses on the analytical investigation of a hybrid steel frame employing assorted connection patterns, including partially-restrained connections of varying strength and stiffness in combination with fully-restrained connections. The dynamic response of a hybrid frame with assorted connections was evaluated by comparing of the results of inelastic static and dynamic analyses conducted on both the hybrid frame and a traditional moment-resisting frame designed according to current specifications. Both frames were based on well documented and studied cases found in the literature (FEMA, 2000). The control frame was designed to reflect the most current American Institute of Steel Construction (AISC) specifications (ANSI/AISC 360, 2010). Its two archetypes respectively include the implementation of reduced beam sections (RBS) and bolted extended end-plates (EEP) steel moment connections as defined in ANSI/AISC 358-10 (ANSI/AISC 358, 2011; Engelhardt et al., 1998; Sumner et al., 2000). Partially-restrained steel connections of increasing strength, stiffness, and energy dissipating characteristics were incorporated in the hybrid frame to force the exterior bays to undergo inelastic deformations earlier than the subsequent interior bays, all the while keeping the central bay fully-restrained. This new connection pattern was developed using two partially-restrained EEP connections in combination with one fully-restrained EEP connection obtained from previous experimental research reports, see (Eatherton et al., 2013; Sumner et al., 2000). Nonlinear static pushover analyses and nonlinear time-history analyses, including incremental dynamic analyses, were conducted to compare the response of the hybrid frame to that of a traditional frame. It was concluded that these hybrid frames show promise for better control of the post-elastic behavior of lateral force resisting systems, offering benefits in terms of energy dissipation and delayed dynamic instability.

Author: Derek A. Marucci
Publisher:
ISBN:
Category :
Languages : en
Pages : 168

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Previous earthquakes have revealed seismic performance issues associated with fully-restrained (FR) welded beam-to-column connections in steel moment frames. Past research has indicated that bolted partially-restrained (PR) connections can serve as viable alternatives for beam-to-column connections to resist lateral loads. This paper addresses the seismic behavior of special moment frames (SMFs) incorporating PR connections. A series of archetypical buildings are modeled in OpenSees using varying levels of stiffness, strength, and strain hardening in the PR beam-to-column connections. Incremental dynamic analyses (IDAs) are performed on the PR archetypes and the results are compared to a typical building archetype constructed with conventional FR connections. The models are subjected to incrementally larger time histories until the frames fail. Maximum interstory drifts, maximum total roof drifts and maximum base shears are recorded for each model throughout the analyses. The PR archetypes are designed and constructed to engage all of the frames in each principal direction to act as the seismic force resisting system (SFRS) whereas the FR archetype is constructed to engage only the perimeter frames as the SFRS. The PR archetypes are modelled to represent a global building stiffness equivalent to the global building stiffness of the conventional FR archetype. The PR connections are modeled with trilinear moment-rotation characteristics using rotational springs. The advantages of using PR frames include smaller member sizes and increased redundancy in the SFRS compared to conventional FR framing. Since most PR connections are of the bolted type, they generally cost less and are easier to assemble. The results of this study reveal that buildings constructed with PR connections that meet or exceed minimal levels of stiffness and strength have very similar seismic performance compared to buildings constructed with FR connections. The recommendation is made to accept PR connections for prequalification in SMFs.

Author: Federal Emergency Agency
Publisher: FEMA
ISBN:
Category :
Languages : en
Pages : 256

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Book Description
This report, FEMA-351 - Recommended Seismic Evaluation and Upgrade Criteria for Existing Welded Steel Moment-Frame Buildings has been developed by the SAC Joint Venture under contract to the Federal Emergency Management Agency (FEMA) to provide structural engineers with recommended criteria for evaluation of the probable performance of existing steel moment-frame buildings in future earthquakes and to provide a basis for updating and revision of evaluation and rehabilitation guidelines and standards. It is one of a series of companion publications addressing the issue of the seismic performance of steel moment-frame buildings. The set of companion publications includes: FEMA-350 - Recommended Seismic Design Criteria for New Steel Moment-Frame Buildings. This publication provides recommended criteria, supplemental to FEMA-302 - 1997 NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, for the design and construction of steel moment-frame buildings and provides alternative performance-based design criteria. FEMA-351 - Recommended Seismic Evaluation and Upgrade Criteria for Existing Welded Steel Moment-Frame Buildings. This publication provides recommended methods to evaluate the probable performance of existing steel moment-frame buildings in future earthquakes and to retrofit these buildings for improved performance. FEMA-352 - Recommended Postearthquake Evaluation and Repair Criteria for Welded Steel Moment-Frame Buildings. This publication provides recommendations for performing postearthquake inspections to detect damage in steel moment-frame buildings following an earthquake, evaluating the damaged buildings to determine their safety in the postearthquake environment, and repairing damaged buildings. FEMA-353 - Recommended Specifications and Quality Assurance Guidelines for Steel Moment-Frame Construction for Seismic Applications. This publication provides recommended specifications for the fabrication and erection of steel moment frames for seismic applications. The recommended design criteria contained in the other companion documents are based on the material and workmanship standards contained in this document, which also includes discussion of the basis for the quality control and quality assurance criteria contained in the recommended specifications. The information contained in these recommended evaluation and upgrade criteria, hereinafter referred to as Recommended Criteria, is presented in the form of specific recommendations for design and performance evaluation procedures together with supporting commentary explaining part of the basis for these recommendations.

Author: SAC Joint Venture. Guidelines Development Committee
Publisher:
ISBN:
Category : Building, Iron and steel
Languages : en
Pages : 260

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Book Description

Author: SAC Joint Venture. Guidelines Development Committee
Publisher:
ISBN:
Category : Building, Iron and steel
Languages : en
Pages : 226

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Book Description

Author: SAC Joint Venture. Guidelines Development Committee
Publisher: FEMA
ISBN:
Category : Building, Iron and steel
Languages : en
Pages : 200

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Book Description

Author: Federal Emergency Agency
Publisher: FEMA
ISBN:
Category :
Languages : en
Pages : 201

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Book Description
This report, FEMA-353 - Recommended Specifications and Quality Assurance Guidelines for Steel Moment-Frame Construction for Seismic Applications has been prepared by the SAC Joint Venture, under contract to the Federal Emergency Management Agency, to indicate those standards of workmanship for structural steel fabrication and erection deemed necessary to achieve reliably the design performance objectives contained in the set of companion publications prepared under this same contract: FEMA-350 - Recommended Seismic Design Criteria for New Steel Moment-Frame Buildings, which provides recommended criteria, supplemental to FEMA-302, 1997 NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, for the design and construction of steel moment-frame buildings and provides alternative performance-based design criteria; FEMA-351 - Recommended Seismic Evaluation and Upgrade Criteria for Existing Welded Steel Moment-Frame Buildings, which provides recommended methods to evaluate the probable performance of existing steel moment-frame buildings in future earthquakes and to retrofit these buildings for improved performance; and FEMA-352 - Recommended Postearthquake Evaluation and Repair Criteria for Welded, Steel Moment-Frame Buildings, which provides recommendations for performing postearthquake inspections to detect damage in steel moment-frame buildings following an earthquake, evaluating the damaged buildings to determine their safety in the postearthquake environment, and repairing damaged buildings. The recommended design criteria contained in these three companion reports are based on the material and workmanship standards contained in this document, which also includes discussion of the basis for the quality control and quality assurance criteria contained in the recommended specifications.

Author: SAC Joint Venture. Guidelines Development Committee
Publisher:
ISBN:
Category : Building, Iron and steel
Languages : en
Pages : 212

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Book Description

Author: Federal Emergency Agency
Publisher: FEMA
ISBN:
Category :
Languages : en
Pages : 11

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Book Description
This report, FEMA-350 - Recommended Seismic Design Criteria for New Steel Moment-Frame Buildings has been developed by the SAC Joint Venture under contract to the Federal Emergency Management Agency (FEMA) to provide organizations engaged in the development of consensus design standards and building code provisions with recommended criteria for the design and construction of new buildings incorporating moment-resisting steel frame construction to resist the effects of earthquakes. It is one of a series of companion publications addressing the issue of the seismic performance of steel moment-frame buildings. The set of companion publications includes: FEMA-350 - Recommended Seismic Design Criteria for New Steel Moment-Frame Buildings. This publication provides recommended criteria, supplemental to FEMA-302 - 1997 NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, for the design and construction of steel moment-frame buildings and provides alternative performance-based design criteria. FEMA-351 - Recommended Seismic Evaluation and Upgrade Criteria for Existing Welded Steel Moment-Frame Buildings. This publication provides recommended methods to evaluate the probable performance of existing steel moment-frame buildings in future earthquakes and to retrofit these buildings for improved performance. FEMA-352 - Recommended Postearthquake Evaluation and Repair Criteria for Welded Steel Moment-Frame Buildings. This publication provides recommendations for performing postearthquake inspections to detect damage in steel moment-frame buildings following an earthquake, evaluating the damaged buildings to determine their safety in the postearthquake environment, and repairing damaged buildings. FEMA-353 - Recommended Specifications and Quality Assurance Guidelines for Steel Moment-Frame Construction for Seismic Applications. This publication provides recommended specifications for the fabrication and erection of steel moment frames for seismic applications. The recommended design criteria contained in the other companion documents are based on the material and workmanship standards contained in this document, which also includes discussion of the basis for the quality control and quality assurance criteria contained in the recommended specifications. The information contained in these recommended design criteria, hereinafter referred to as Recommended Criteria, is presented in the form of specific design and performance evaluation procedures together with supporting commentary explaining part of the basis for these recommendations.