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FEMA 547 Techniques for the Seismic Rehabilitation of Existing Buildings

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FEMA 547 Techniques for the Seismic Rehabilitation of Existing Buildings Techniques for the Seismic Rehabilitation of Existing Buildings FEMA 547/2006 Edition Cover Photo Courtesy of Kelly Peterson, University of Utah Cover Photo: Unbonded Steel Braces are used as part of the seismic rehabilitation of the J. Willard Marriott Library on the University of Utah campus. FEMA provided partial funding of this project through the Pre-Disaster Mitigation Competitive (PDM-C) grant program. Techniques for the Seismic Rehabilitation of Existing Buildings FEMA 547 – October 2006 Prepared by: Rutherford & Chekene (R & C) Consulting Engineers (Subconsultant) under contract with National Institute of Standards and Technology (NIST). Project funding was provided by the Federal Emergency Management Agency (FEMA) through an Interagency Agreement - EMW-2002-IA-0098 with the National Institute of Standards and Technology (NIST). Additional funding was provided by the following agencies: General Services Administration (GSA) Air Force Civil Engineer Support Agency (AFCESA) Naval Facilities Engineering Command (NAVFAC) U.S. Bureau of Reclamation (USBR) Notice Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of the Federal Emergency Management Agency, the General Services Administration (GSA), the Air Force Civil Engineer Support Agency (AFCESA), the National Institute of Standards and Technology (NIST), the Naval Facilities Engineering Command (NAVFAC), and Rutherford & Chekene Consulting Engineers (R&C), and R&C’s subconsultants. Additionally, neither FEMA, R&C nor its subconsultants, AFCESA, FEMA, GSA, NIST, NAVFAC, USBR, or other ICSSC member agencies, nor any of their employees, makes any warranty, expressed or implied, nor assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, product, or process included in this publication. Users of information from this publication assume all liability arising from such use. ii Preface This seismic rehabilitation techniques document is part of the National Earthquake Hazards Reduction Program (NEHRP) family of publications addressing seismic rehabilitation of existing buildings. It describes common seismic rehabilitation techniques used for buildings represented in the set of standard building types in FEMA seismic publications. This document supersedes FEMA 172: NEHRP Handbook for Seismic Rehabilitation of Existing Buildings, which was published in 1992 by the Federal Emergency Management Agency (FEMA). Since then, many rehabilitation techniques have been developed and used for repair and rehabilitation of earthquake damaged and seismically deficient buildings. Extensive research work has also been carried out in support of new rehabilitation techniques in the United States, Japan, New Zealand, and other countries. Available information on rehabilitation techniques and relevant research results for commonly used rehabilitation techniques are incorporated in this document. The primary purpose of this document is to provide a selected compilation of seismic rehabilitation techniques that are practical and effective. The descriptions of techniques include detailing and constructability tips that might not be otherwise available to engineering offices or individual structural engineers who have limited experience in seismic rehabilitation of existing buildings. A secondary purpose is to provide guidance on which techniques are commonly used to mitigate specific seismic deficiencies in various model building types. FEMA sincerely thanks all of the federal agencies that contributed funds toward completing this report as well as the members of the Interagency Committee for Seismic Safety in Construction (ICSSC) Subcommittee 1, the Technical Update Team, and all of the federal and private sector partners for their efforts in development, review and completion of this publication. iii Acknowledgments Private sector consultants working with the Subcommittee 1, Standards for New and Existing Buildings, of the Interagency Committee on Seismic Safety in Construction (ICSSC) produced this document. The following persons contributed to this document. Contractors Technical Update Team William T. Holmes, Team Leader, Rutherford & Chekene, San Francisco Bret Lizundia, Project Manager and Editor, Rutherford & Chekene, San Francisco James O. Malley, Degenkolb Engineers, San Francisco Kelly Cobeen, Cobeen & Associates Structural Engineering, Inc., Lafayette, California Contractor Staff Rutherford & Chekene: Afshar Jalalian, Gyimah Kasali, Mark Moore, Rich Niewiarowski, and Karl Telleen Degenkolb Engineers: Jack Hsueh Consultant on Foundation Rehabilitation Techniques Craig Comartin, CDComartin, Inc., Stockton, California Other Figures shown in Table 4-1 and repeated later in the text were adapted from those originally rendered by Anthony Alexander of Palo Alto, California for a separate FEMA-funded project. Project Review Panel J. Daniel Dolan, Washington State University Terry Dooley, Consultant Kurt Gustafson, American Institute of Steel Construction Robert D. Hanson, FEMA Consultant Neil M. Hawkins, Consultant James R. Harris, J. R. Harris and Company Bela Palfalvi, General Services Administration (representing ICSSC) Daniel Shapiro, SOH and Associates FEMA Project Officer Cathleen Carlisle, DHS-FEMA, Washington, DC iv ICSSC Subcommittee 1 H. S. Lew, Chair National Institute of Standards and Technology John Baals Department of Interior, U.S. Bureau of Reclamation Krishna Banga Department of Veteran Affairs Rosana Barkawi Department of Agriculture, U.S. Forest Service James Binkley U.S. Postal Service Larry Black Department of Army Cathleen Carlisle Federal Emergency Management Agency James A. Caulder Air Force Civil Engineering Support Agency Cathy Chan Department of Justice, Bureau of Prisons Harish Chander Department of Energy Anjana Chudgar U.S. Army Corps of Engineers Ronald Crawford Department of Housing and Urban Development Joseph Corliss Department of Health and Human Services Nathaniel Foster Tennessee Valley Authority Freda Gerard International Broadcasting Bureau Colleen Geraghty Department of Labor, Office of Safety and Health Asadour Hadjian Defense Nuclear Facility Safety Board Owen Hewitt Naval Facilities Engineering Command Howard Kass National Aeronautics and Space Administration Regina Larrabee Department of Commerce Catherine Lee General Services Administration S. C. Liu National Science Foundation Rita Martin Department of Transportation Thomas Myers Smithsonian Institution Thomas Nelson Lawrence Livermore National Laboratory Dai Oh Department of State, Office of Foreign Buildings Bela Palfalvi General Services Administration Erdal Safak Department of Interior, U.S. Geological Survey Subir Sen Department of Energy C.A. Stillions Architect of the Capital Lawrence Swanhorst Environmental Protection Agency Steven Sweeney Army Construction & Engineering Research Laboratory Doris Turner Federal Aviation Administration Terry Wong National Park Services v This page is intentionally left blank. vi Techniques for the Seismic Rehabilitation of Existing Buildings: FEMA 547 Table of Contents Table of Contents Notice.............................................................................................................................................. ii Preface...........................................................................................................................................iii Acknowledgments ........................................................................................................................ iv PART 1 - OVERVIEW Chapter 1 - Introduction ...........................................................................................................1-1 1.1 Overview....................................................................................................................... 1-1 1.2 Purpose and Goals......................................................................................................... 1-2 1.3 Audience ....................................................................................................................... 1-2 1.4 Scope............................................................................................................................. 1-2 1.5 Other Resources............................................................................................................ 1-3 1.6 Organization of the Document...................................................................................... 1-4 1.6.1 Part 1 – Overview ......................................................................................... 1-6 1.6.2 Part 2 – Rehabilitation Techniques for FEMA Model Buildings................. 1-6 1.6.3 Part 3 – Rehabilitation Techniques for Deficiencies Common to Multiple Building Types........................................................... 1-6 1.7 Disclaimers ................................................................................................................... 1-7 1.8 References..................................................................................................................... 1-7 Chapter 2 - Seismic Vulnerability ............................................................................................2-1 2.1 Introduction................................................................................................................... 2-1 2.2 Seismic Evaluation........................................................................................................2-1
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