UCLA

An overview is presented of the authors’ ongoing investigation of the performance of a railroad bridge and adjacent highway bridge during the 2010 El Mayor-Cucapah earthquake in Baja California, Mexico. A span of the pile-supported railroad bridge collapsed due to movement of a pier from lateral spreading. The highway bridge, supported on drilled shafts, suffered moderate structural damage but did not collapse. An overview of the site, structural details of the bridges, and the proposed geotechnical explorations and analyses are presented. The Pacific Earthquake Engineering Research Center (PEER) recently published “Recommended Design Practice for Pile Foundations in Laterally Spreading Ground,” which synthesizes the last decade of research on the topic. Using the results from planned geotechnical investigation, the authors intend to analyze the bridges according to the PEER guidelines. The case studies will provide valuable insight for validating the recommended guidelines.