<p> TRB 2007 Meeting</p><p>SESSION on ”RESIDUAL SHEAR STRENGTH OF LIQUEFIED SOIL” </p><p>Sponsored by TRB COMMITTEE on SEISMIC DESIGN OF BRIDGES – AFF50, SUB-COMMITTEE on GEO SEISMIC CONCERNS</p><p>Moderators: Dr. Edward Kavazanjian, Jr. Thomas Cooling, P.E. Associate Professor and Interim Chair Vice President Dept. of Civil and Environ. Engineering Geotechnical Services Arizona State University URS Corporation Mail Stop 55306 1001 Highlands Plaza Dr. West Tempe, AZ 85287-5306 St. Louis, MO. 63110 Tel: (480) 727-8566 Tel: (314) 743-4148 Fax: (480) 965-0557 Fax: (314) 429-0462 e-mail: [email protected] email: [email protected] ------The post-liquefaction residual shear strength is often the most important parameter in seismic performance analyses of bridges founded upon of liquefied soil. Small differences in the value of the residual shear strength can often be the difference between a finding of acceptable performance and a finding that redesign or retrofit is required for the foundation system. However, large uncertainties exist in the value of this key parameter. Many engineers still employ the 1990 recommendations of Seed and Harder in determining the value of residual shear strength, despite the fact that the band of recommended values is about 20 kPa wide for a given blow count and the recommended values are based upon an “equivalent clean sand blow count”. Recent research promises to narrow the uncertainty associated with the evaluation of the residual strength of liquefied soils, facilitating more cost effective and more reliable foundation design. In this session, findings from four ongoing research programs on the residual shear strength of liquefied soils are presented. ------</p><p>Title of Presentation: Recommendations for Residual Shear Strength of Liquefied Soils</p><p>Author: Prof. Ross Boulanger, PhD, PE</p><p>Affiliation: Associate Professor Department of Civil and Environmental Engineering University of California - Davis</p><p>Mailing address: One Shields Avenue Davis, California 95616</p><p>Phone #: (530) 752-2947 Fax #: (530) 752-7872 E-mail: [email protected] ______Title of Presentation: Shear strength of liquefied soils using strength ratios</p><p>Author: Prof. Scott M. Olson, PhD, PE</p><p>Affiliation: Assistant Professor Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign</p><p>Mailing address: 2230d Newmark Civil Engineering Laboratory 205 N. Mathews Ave. Urbana, Illinois 61801</p><p>Phone #: (217) 265-7584 Fax #: (217) 265-8041 E-mail: [email protected] ______</p><p>Title of Presentation: Operational post-liquefaction strength from state parameter approach: framework and experience</p><p>Author: Dr. Mike Jefferies, C. Eng.</p><p>Affiliation: Associate Golder Associates</p><p>Mailing address: Landmere Lane, Edwalton Nottingham, England NG12 4DG</p><p>Phone #: 9-011-44-115-9456544 Fax #: 9-011-44-115-9456540 E-mail: [email protected] ______</p><p>Title of Presentation: Assessment of Residual Strength During Blast Liquefaction Experiments with Deep Foundations</p><p>Author: Dr. Kyle Rollins</p><p>Affiliation: Professor Department of Civil and Environmental Engineering Brigham Young University</p><p>Mailing address: 368 Clyde Building Provo, Utah 84602</p><p>Phone #: (801) 422-6334 Fax #: (801) 422-0159 E-mail: [email protected]</p>