[PDF] Collapse Risk Assessment Of Steel Moment Resisting Frames Designed With Deep Wide Flange Columns In Seismic Regions eBook

Author : Ahmed Elkady
Publisher :
Page : pages
File Size : 44,2 MB
Release : 2016
Category :
ISBN :

GET BOOK

"In the context of Performance-Based Earthquake Engineering, there is an increasing need to quantify the collapse resistance of frame buildings under severe ground-motion shaking. The primary objective of this thesis is to advance, through experimental and analytical research, knowledge on the collapse risk assessment of steel frame buildings with steel moment-resisting frames (MRFs) designed in highly seismic regions in North America. Emphasis is placed on the characterization of the steel column hysteretic behaviour as well as the composite floor action and the destabilizing effects of the gravity framing system of steel frame buildings with steel MRFs. The dynamic stability of beam-columns that utilize deep and slender wide-flange cross sections is investigated through full-scale experimental testing. Some of the unique features of the experimental program involve realistic boundary conditions, unidirectional and bidirectional lateral loading and the use of various types of lateral loading protocols. The experimental data provide insight on the damage progression and deteriorating mechanisms observed in wide-flange beam-columns. The hysteretic behaviour of a wide range of cross-sections is further evaluated through a corroborating finite element (FE) parametric study. The findings of the coordinated experimental and analytical research are used to proposed recommendations for the seismic design of steel beam-columns in steel MRFs. A comprehensive system-level analytical study is then conducted in order to evaluate the collapse risk of steel frame buildings with special moment-resisting frames (SMFs) as per ASCE (2010) and Type D Ductile steel MRFs per NBCC (2010). The contributions of the composite floor slab and the gravity framing system are included in the analytical model representations of the steel frame buildings. These contributions have been historically ignored in prior analytical studies. In that respect, a practical approach is developed for modeling (a) the non-symmetric hysteretic behaviour of composite steel beams and panel zones as part of fully-restrained beam-to-column connections; and (b) the hysteretic behaviour of steel beams as part of conventional single-plate shear-tab beam-to-column connections. The collapse risk of typical steel frame buildings with steel MRFs is evaluated based on advanced collapse metrics such as the mean annual frequency of collapse. Based on the findings of the comprehensive system-level analytical study, the strong-column/weak-beam ratio that is typically used in the seismic design of steel MRFs is re-assessed such that a uniform probability of collapse can be achieved over the life expectancy of the steel frame buildings. A new definition of system overstrength (i.e., dynamic overstrength factor) is also proposed." --

Author : Yusuke Suzuki
Publisher :
Page : pages
File Size : 24,56 MB
Release : 2019
Category :
ISBN :

GET BOOK

"Capacity design principles have reduced the earthquake-induced collapse risk in steel frame buildings designed in seismic regions. Experiments suggest that the steel column behaviour may be significantly compromised due to member and local geometric instabilities, thereby increasing the associated collapse risk and likelihood of building demolition due to residual deformations. The High Yield Point (HYP400) steel is a steel material that has a higher yield stress and notch toughness but less strain hardening than conventional mild steels. HYP400 steel could enhance capacity design principles, such as the strong-column-weak-beam (SCWB) ratio when they are utilized in steel columns and potentially increase the collapse capacity of steel moment resisting frames (MRFs) under earthquake shaking. This thesis advances the state-of-knowledge through a multi-scale (from material to system) level study to assess the potential use of high-performance steel materials in minimizing earthquake-induced collapse of steel MRFs. The primary focus is on the characterization of the collapse behaviour of HYP400 and conventional steel hollow square section (HSS) columns by means of experimental testing and corroborating numerical simulations. Dual-parameter collapse-consistent loading histories (i.e., axial load and lateral drift demands) are developed to better quantify the flexural and axial demands in both interior and end columns in steel MRFs. These protocols reflect the asymmetric drifting of a building in one primary loading direction prior to dynamic instability ("ratcheting"). They also reflect the seismic demands imposed into steel columns within a steel MRF subjected to near-fault and long-duration ground motions. A landmark experimental program is conducted that characterizes the collapse behaviour of wide-flange and HSS steel columns under cyclic loading. The experimental program highlights the differences in the seismic demands and failure modes observed in steel columns depending on the imposed lateral and axial loading history, expected ground motion characteristics and building topology. It is shown that column axial shortening dominates the steel column stability. The hysteretic behaviour of HSS steel columns is further evaluated through corroborating finite element (FE) simulations. The steel column pre- and post-buckling behaviour is fully characterized depending on the type of steel material including the HYP400 steel. The FE results provide insight on the main differences of the lateral and axial damage progression between interior and end columns within the same steel MRF bay. The experimental data and corroborating finite element studies provide the basis for the development of a versatile steel column deterioration model that can explicitly simulate the axial-bending interaction, the column axial shortening due to local buckling induced softening and the cyclic deterioration in the column's strength and stiffness. Local buckling-induced softening is modeled through the development of an equivalent stress-strain formulation that includes a softening branch and can be fully characterized through conventional stub column tests. System level dynamic collapse simulation studies are conducted with over 80 archetype buildings with steel MRF systems ranging from 2 to 12-stories. Emphasis is placed on the importance of column axial shortening on the seismic performance of steel MRFs. It is shown that depending on the ground motion type, column axial shortening may result into slab tilting and catenary action prior to collapse. It is also shown that the use of the HYP400 steel columns can potentially enhance the collapse capacity of steel MRFs and reduce the expected residual lateral and vertical deformations in the aftermath of earthquakes." --

Author : Joseph Gilroy
Publisher :
Page : 0 pages
File Size : 41,18 MB
Release : 2022
Category :
ISBN :

GET BOOK

Recent research has investigated a low damage seismic design concept for steel moment resisting frames (MRFs): the moment resisting fuse connection. Fuse connections are moment resisting connections that yield prior to the beam or column they connect. The connection acts as an easily repairable structural fuse of the seismic system instead of the beam, which is the typical fuse in a steel moment resisting frame designed to resist seismic loads, which can be very challenging and costly to repair after an earthquake. In most proposed fuse connections, energy dissipation is achieved by means of connection component yielding or friction slip. In AISC 358-16 (AISC, 2016c), the first prequalified fuse connection was added to the specification: the Simpson Strong-TieTM Yield-Link® (SST-YL) connection. Although the connection has shown sufficient strength and ductility at large levels of drift to reach prequalified status, there is some concern that steel MRFs with optimized fuse connections will not have the typical overstrength of traditional steel MRFs, which are usually controlled by drift limits rather than strength requirements. This concern raises the question: Are steel moment resisting frames with fuse connections adequately designed to prevent sidesway collapse during earthquakes when using typical seismic performance factors (R = 8, C [subscript d] = 5.5, and Ω0 = 3.0) for steel special moment resisting frames (SMRFs)? To investigate this concept, four three-bay steel special moment resisting frames with fuse connections were designed using provisions in ASCE7-16 (ASCE, 2017), AISC 341-16 (AISC, 2016a), AISC 360-16 (AISC, 2016b), and AISC 358-16s20 (AISC, 2020) with steel SMRF seismic performance factors. These frames were 2 stories, 4 stories, 6 stories, and 8 stories in height. These four archetypes were also redesigned with modified capacity design requirements more comparable to typical steel MRFs for a total of four design cases. These designs were evaluated using the FEMA P-695 methodology (FEMA, 2009) to determine if they have adequate collapse capacity. Different post-yield behaviors and failure criteria were modeled to determine their effect on system collapse capacity. Nonlinear pushover and response history analyses were done using OpenSEES (McKenna et al., 2010). The results of this investigation support that the seismic performance factors for typical SMRF frames are appropriate for use in SMRFs with fuse connections. However, there are several sources of uncertainty that require further investigation and research to determine to what extent this conclusion is accurate, particularly for new fuse connections that may be proposed. Suggestions for future research into numerical modeling and analysis of SMRFs with fuse connections are presented

Author : Federal Emergency Agency
Publisher : FEMA
Page : 11 pages
File Size : 24,84 MB
Release : 2013-03-16
Category :
ISBN :

GET BOOK

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.

Author : Fadzli Mohamed Nazri
Publisher : Penerbit USM
Page : pages
File Size : 13,29 MB
Release : 2015-12-01
Category : Architecture
ISBN : 9838618942

GET BOOK

This research book presents the fundamental work related to the prediction of collapse load for a moment-resisting steel frame (MRSF) subjected to earthquake forces.It demonstrates the extensive work in nonlinear analysis with particular reference to pushover analysis (POA) and incremental dynamic analysis (IDA), and deliberates at length the historical background for each method. More importantly, the book simplifies the collapse prediction process of a structure based on analytical expression. In addition, this book describes the MRSF which was designed according to Eurocode(s). This bookserves as a guide and reference for practitioners and students. Universiti Sains Malaysia, Penerbit Universiti Sains Malaysia

Author : Federico Mazzolani
Publisher : CRC Press
Page : 686 pages
File Size : 29,51 MB
Release : 2000-04-27
Category : Technology & Engineering
ISBN : 9780415235778

GET BOOK

An unexpected brittle failure of connections and of members occurred during the last earthquakes of Northridge and Kobe. For this reason a heightened awareness developed in the international scientific community, particularly in the earthquake prone countries of the Mediterranean and Eastern Europe, of the urgent need to investigate this topic. The contents of this volume result from a European project dealing with the 'Reliability of moment resistant connections of steel frames in seismic areas' (RECOS), developed between 1997 and 1999 within the INCO-Copernicus joint research projects of the 4th Framework Program. The 30 month project focused on five key areas: *Analysis and syntheses of research results, including code provisos, in relation with the evidence of the Northridge and Kobe earthquakes; *Identification and evaluation through experimental means of the structural performance of beam-to-column connections under cyclic loading; *Setting up of sophisticated models for interpreting the connection response; *Numerical study on the connection influence on the seismic response of steel buildings; *Assessment of new criteria for selecting the behaviour factor for different structural schemes and definition of the corresponding range of validity in relation of the connection typologies.

Author : Federico Mazzolani
Publisher : CRC Press
Page : 516 pages
File Size : 50,77 MB
Release : 2012-09-10
Category : Architecture
ISBN : 1482271346

GET BOOK

A state-of-the-art summary of recent developments in the behaviour, analysis and design of seismic resistant steel frames. Much more than a simple background volume, it gives the most recent results which can be used in the near future to improve the codified recommendations for steel structures in seismic zones. It contains new material which cann

Author : Vitiea Noeun
Publisher :
Page : 156 pages
File Size : 23,17 MB
Release : 2012
Category :
ISBN : 9781267675965

GET BOOK

This research focuses on safety assessment of steel special moment-resisting frames (SMFs). Moment-resisting frames are one common type of lateral load-resisting systems that have been used in steel buildings for almost 5 decades. After the 1994 Northridge earthquake, the reduced beam section (RBS) connection was introduced and widely recognized as one of the prequalified beam-to-column connections for use in a structural steel special moment-resisting frame. In this study, W14 and W24 column sections were used in the moment-resisting frame designs with the RBS connection to further compare their seismic performances. Moreover, the deflection amplification factors, Cd = 5.5 and Cd = 8, were also utilized in the designs of the special SMF. Briefly, a total of 12 special SMF structures were developed, and were divided into 3 groups: 5-story, 10-story, and 15-story. Each group contained 4 structures, such that two designs of W14 and W24 columns where Cd equaled 5.5 and another two designs of the same column depths where Cd equaled 8. The nonlinear analyses, nonlinear static and nonlinear dynamic analysis, were later implemented to assess the collapse performance of these 12 archetypes. The nonlinear static analysis was used to determine system overstrength and ductility, and the nonlinear dynamic analysis was performed to obtain median collapse intensity and collapse margin ratio of archetypes. Finally, an appropriate Cd factor was determined according to the height of archetype, and the comparison of seismic performances of W24 and W14 column sections was evaluated.