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Framework for Improving Resilience of Bridge Design U.S. Department of Transportation Federal Highway Administration Framework for Improving Resilience of Bridge Design Publication No. FHWA-IF-11-016 January 2011 Notice This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for use of the information contained in this document. This report does not constitute a standard, specification, or regulation. Quality Assurance Statement The Federal Highway Administration provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement. Framework for Improving Resilience of Bridge Design Report No. FHWA-IF-11-016 January 2011 Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. FHWA-IF-11-016 4. Title and Subtitle 5. Report Date Framework for Improving Resilience of Bridge Design January 2011 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Brandon W. Chavel and John M. Yadlosky 9. Performing Organization Name and Address 10. Work Unit No. HDR Engineering, Inc. 11 Stanwix Street, Suite 800 11. Contract or Grant No. Pittsburgh, Pennsylvania 15222 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered Office of Bridge Technology Technical Report Federal Highway Administration September 2007 – January 2011 1200 New Jersey Avenue, SE Washington, D.C. 20590 14. Sponsoring Agency Code 15. Supplementary Notes Contracting Officer’s Technical Representative (COTR): Raj Ailaney, HIBT-10 16. Abstract Bridges are an integral and important part of the highway infrastructure system and need to be designed to provide the necessary safety for the traveling public. Bridge failures can result in the disruption of commerce and services, significant repair costs, and most importantly the loss of human life. Performing a failure analysis during design, coupled with the review of past bridge failures, can help to avoid the need to initiate investigations and perform forensic engineering after a failure. This is the motivation for the development of this Framework. The development of this Framework considers bridge failures that resulted in collapse, service closures, major repairs, or other significant issues that occurred while the bridge was in service or during construction. A fault tree methodology is adopted in the Framework, where lessons from past bridge failures are used extensively to identify potential events that could lead to a bridge failure. A bridge designer, conscientiously or unconscientiously, goes through a fault-tree analysis mentally while ensuring that the design is devoid of weaknesses that could lead to bridge malfunction or failure. This Framework can provide a starting point for the less than senior engineer to jump start a conscience evaluation process, and is expected to be of interest to students and instructors of bridge engineering, bridge owners, bridge designers, inspectors, fabricators, contractors, and maintenance personnel. 17. Key Words 18. Distribution Statement Bridge Failure, Lessons Learned, Fault Tree, Bridge No restrictions. This document is available to the public through Design, Bridge Construction the National Technical Information Service, Springfield, VA 22161. 19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No of Pages 22. Price Unclassified Unclassified Form DOT F 1700.7 (8-72) Reproduction of completed pages authorized i ii Framework for Improving Resilience of Bridge Design Table of Contents FOREWORD .................................................................................................................................. 1 ACKNOWLEDGMENTS .............................................................................................................. 2 1.0 INTRODUCTION ................................................................................................................. 3 1.1 Definition of Failure ........................................................................................................ 4 1.2 Redundancy...................................................................................................................... 4 1.3 Bridge Inspection and Maintenance................................................................................. 5 1.4 Design Errors and Omissions........................................................................................... 6 1.5 Quality Control and Quality Assurance Programs ........................................................... 6 1.6 Fault Tree Diagram .......................................................................................................... 7 2.0 Steel Girder Bridge Failure Framework ................................................................................ 9 2.1 Design/Operation Category ........................................................................................... 10 2.1.1 Superstructure – Girders ....................................................................................... 11 2.1.2 Superstructure – Cross Frames / Diaphragm ........................................................ 19 2.1.3 Superstructure – Bearings ..................................................................................... 19 2.1.4 Superstructure – Concrete Deck/Railings ............................................................. 21 2.2 Inspection Category ....................................................................................................... 22 2.3 Construction Category ................................................................................................... 23 2.3.1 Steel Erection ........................................................................................................ 24 2.3.2 General Construction ............................................................................................ 26 2.4 Fabrication Process Category ........................................................................................ 28 3.0 Precast Concrete Girder Bridge Failure Framework ........................................................... 31 3.1 Design/Operation Category ........................................................................................... 32 3.1.1 Superstructure – Girders ....................................................................................... 32 3.1.2 Superstructure - Bearings ...................................................................................... 41 3.1.3 Superstructure - Concrete Deck/Railings.............................................................. 41 3.2 Inspection Category ....................................................................................................... 42 3.3 Construction Category ................................................................................................... 43 3.3.1 Girder Erection...................................................................................................... 44 iii 3.3.2 General Construction ............................................................................................ 44 3.4 Fabrication Process Category ........................................................................................ 44 4.0 Substructure Failure Framework.......................................................................................... 46 4.1 General ........................................................................................................................... 47 4.2 Concrete Substructure .................................................................................................... 51 4.3 Steel Substructure .......................................................................................................... 51 5.0 Complex Bridge Failures – Lessons Learned ...................................................................... 53 5.1 Steel Truss Bridges ........................................................................................................ 53 5.1.1 Quebec Bridge, 1907 ............................................................................................ 53 5.1.2 Yadkin River Bridge, 1975 ................................................................................... 54 5.1.3 Minneapolis I-35W Bridge, 2007 ......................................................................... 54 5.2 Suspension Bridges ........................................................................................................ 56 5.2.1 Tacoma Narrows Bridge Collapse, 1940 .............................................................. 56 5.2.2 Silver Bridge, 1967 ............................................................................................... 56 5.3 Cable-Stayed Bridges..................................................................................................... 57 6.0 Conclusions .......................................................................................................................... 58 7.0 References ............................................................................................................................ 59 iv List of Figures Figure 2-1 Steel girder bridge
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