AN INTEGRATED APPROACH TO THE SITE INVESTIGATION AND EARTHQUAKE RESPONSE ANALYSIS FOR THE SAN FRANCISCO-OAKLAND BAY BRIDGE EAST SPAN REPLACEMENT

The integrated geotechnical approach has provided efficient, cost effective, accurate data for design and construction of the San Francisco-Oakland Bay Bridge (SFOBB) East Span Replacement. The new structure will span over 4 km from the Yerba Buena Island to the Oakland shore, and will carry over 280,000 motor vehicles per day. Geotechnical studies included land and marine geophysical surveys, conventional land drilling, and sophisticated marine drilling and in situ testing. An onboard laboratory allowed the collected subsurface data to be immediately incorporated into the project geotechnical Geographic Information System. This approach also allowed site characterization and earthquake site response analyses to proceed concurrently with the site investigation, thus shortening the overall timeframe for design. This paper describes the marine exploration and the site characterization activities for the project.