FHWA-NJ-2005-002 SEISMIC ANALYSIS OF RETAINING WALLS, BURIED STRUCTURES, EMBANKMENTS, AND INTEGRAL ABUTMENTS FINAL REPORT July 2005 Submitted by Husam Najm, Assistant Professor Suhail Albhaisi, Graduate Research Assistant Hani Nassif, Associate Professor Parham Khoshkbari, Graduate Research Assistant Nenad Gucunski, Professor Dept. of Civil & Environmental Engineering Center for Advanced Infrastructure & Transportation (CAIT) Rutgers, The State University Piscataway, NJ 08854-8014 NJDOT Research Project Manager Mr. Anthony Chmiel In cooperation with New Jersey Department of Transportation Bureau of Research and U.S. Department of Transportation Federal Highway Administration Disclaimer Statement "The contents of this report reflect the views of the author(s) who is (are) responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the New Jersey Department of Transportation or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation." The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. This document is disseminated under the sponsorship of the Department of Transportation, University Transportation Centers Program, in the interest of information exchange. The U.S. Government assumes no liability for the contents or use thereof. TECHNICAL REPORT STANDARD TITLE PAGE 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. FHWA-NJ-2005-002 4. Title and Subtitle 5. Report Date Seismic Analysis of Retaining Walls, Buried Structures, July 2005 Embankments, and Integral Abutments 6. Performing Organization Code CAIT/Rutgers 7. Author ( s ) Husam Najm, Hani Nassif, Nenad Gucunski, 8. Performing Organization Report No. FHWA-NJDOT-2005-002 Suhail Albhaisi, and Parham Khoshkbari 9. Performing Organization Name and Address 10. Work Unit No. Center for Advanced Infrastructure and Transportation (CAIT) Rutgers, The State University 11. Contract or Grant No. Piscataway, NJ 08854-8014 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address Final Report New Jersey Department Federal Highway Administration 1/01/2003 - 12/31/2004 of Transportation, P.O. Box 600 U.S. Department of Transportation Trenton, NJ 08625 Washington, D.C. 14. Sponsoring Agency Code 15. Supplementary Notes [email protected] 16. Abstract This study evaluates the impact of the newly recommended seismic design guidelines from NCHRP 12-49 on seismic design of bridges in New Jersey. It also provides seismic design criteria and guidelines for integral abutments, retaining walls, embankments, and buried structures. The study provides an overall review of the recommended guidelines and compares them to the current AASHTO LRFD specifications. It provides recommendations on seismic hazard and performance objectives and soil site factors for New Jersey that incorporates design criteria from NCHRP 12-49 guidelines, AASHTO LRFD specifications, South Carolina seismic design criteria, and NYCDOT seismic design guidelines. The study also includes two design examples based on the NCHRP 12-49 guidelines and current AASHTO LRFD specifications. Research results showed that: (1) the MCE ground motion level adopted by NCHRP 12-49 which has a 2500 years return is acceptable for safety evaluation of ‘critical bridges’ in New Jersey, (2) a reduced (2/3 MCE) ground motion is acceptable for safety evaluation of ‘non-critical’ bridges, (3) soil-site factors have increased dramatically for soft soils subjected to small ground motions which will have an impact on seismic design in Southern Jersey, (4) the USGS National Seismic Hazard Maps adopted by NCHRP 12- 49 for ground motion accelerations may not necessarily reflect the actual geological soil conditions and realistic hazard levels in New Jersey, and (5) NCHRP12-49 SDAP E (pushover analysis) is preferable for the seismic analysis and design of bridges in New Jersey, and (6) NCHRP12-49 SDAP C is a relatively simplified design procedure for many bridges and should be used when applicable. Recommendations from this study include adoption of NCHRP 12-49 subject to above conclusions. However, there is a need to: (1) predict extreme earthquake events for New Jersey and the Northeast United States, (2) prepare Seismic Hazard Maps for bridge design in New Jersey and re-evaluate NCHRP 12-49 soil-site factors proposed for New Jersey, and (3) quantify damage level by using structural capacity and demand. 17. Key Words 18. Distribution Statement NCHRP 12-49, Integral abutments, Response spectra, Soil factors, Seismic hazard, Performance levels, Buried structures, Design criteria. 19. Security Classif (of this report) 20. Security Classif. (of this page) 21. No of Pages 22. Price Unclassified Unclassified 160 Form DOT F 1700.7 (8-69) Acknowledgements The authors wish to acknowledge the support of the personnel from the New Jersey Department of Transportation (NJDOT). In particular the authors would like to thank Mr. Anthony Chmiel, Research Project Manager and Mr. Nicholas Vitillo, Manager of NJDOT Bureau of Research for their support and constructive comments. The authors also would like to thank Mr. Harry Capers of the NJDOT Office of Transportation Safety and Mr. Jose Lopez and Ms Hannah Cheng of the NJDOT Bureau of Structural Engineering for their technical support and helpful suggestions and comments throughout this research. The authors also would like to thank Rutgers graduate students Ozgur Bezgin, Hashem Khasawneh, and Sardar Nabi, and for their work on this project. The financial support of this project was provided by the State of New Jersey Department of Transportation (NJDOT) and the Federal Highway Administration (FHWA). Mr. Anthony Chmiel was the NJDOT Research Project Manager. Drs. Husam Najm, Hani Nassif, and Nenad Gucunski from Rutgers University were the project Principal Investigators. ii TABLE OF CONTENTS SUMMARY .................................................................................................................... 1 INTRODUCTION ........................................................................................................... 3 Background................................................................................................................ 4 Objectives .................................................................................................................. 8 Brief Review of NCHRP 12-49 Guidelines ................................................................. 8 NCHRP 12-49 Design Philosophy ............................................................................. 9 NCHRP 12-49 Design Earthquakes for New Jersey................................................ 11 Effect of Soil Type on NCHRP 12-49 Design Earthquake........................................ 13 NCHRP 12-49 Guidelines for Design and Analysis Procedures ............................. 20 Comparison of NCHRP 12-49 Spectra and Site-Specific Response Spectra ......... 21 Current Seismic Design Criteria in New Jersey ...................................................... 24 Proposed Seismic Hazards and Performance Levels for New Jersey ..................... 26 NCHRP 12-49 Ground Motion Levels in New Jersey............................................... 28 NCHRP 12-49 Design Accelerations And Analysis Procedures For The EXP And MCE Earthquakes For Various Counties In New Jersey ................................ 28 Seismic Design Criteria and Guidelines for Abutments ........................................... 33 Seismic Design Criteria and Guidelines for Retaining Walls ................................... 37 Seismic Design Criteria and Guidelines for Embankments ..................................... 40 Seismic Design Criteria and Guidelines for Buried Structures ................................. 44 Conclusions ................................................................................................................. 51 Recommendations....................................................................................................... 52 APPENDIX A- Abutment Design Examples ................................................................. 54 APPENDIX B- Stiffness of Abutments and Retaining Walls For Seismic Design......... 96 APPENDIX C- Seismic Design of Embankments....................................................... 108 APPENDIX D- Additional Guidelines on Seismic Design of Buried Structures With Design Examples....................................................................... 119 REFERENCES .......................................................................................................... 149 iii LIST OF FIGURES Page Figure 1. USGS Seismic Hazard Map for the Continental United States……………. 5 Figure 2. Seismic history of New Jersey, Metro New York, and Long Island from 1638 to 1998………………………………………………………………. 6 Figure 3. Design response spectra from AASHTO LRFD and NCHRP 12- 49 with various return periods………………………………………………… 12 Figure 4. Design response spectra from AASHTO LRFD and NCHRP 12-49 MCE and EXP earthquakes………………………………………….. 13 Figure 5. Geological map of New Jersey (1994)………………………………………. 15 Figure 6. NYCEM Soil Characterization of NYC and Northern New Jersey soil conditions according to NEHRP soil classification……………………. 16 Figure 7. Design response spectra for NCHRP 12-49 MCE earthquake for various soil conditions in Northern New Jersey…………………………….