New Developments in Cable-Stayed Bridge Design, San Francisco

This paper describes the preliminary design process for a state-of-the-art single-tower, cable-stayed solution for the signature span of the San Francisco-Oakland Bay Bridge East Span Seismic Safety Project. This design development was carried out in the spring of 1998 as part of the seismic safety improvement for the vulnerable east spans that were damaged in the Loma Prieta earthquake in 1989. Technically progressive developments include tower shear and tension links, a dual plane splayed stay cable layout, a "double-wide" steel/concrete composite deck system utilizing precast lightweight concrete, and post-tensioned steel elements. This paper describes the design issues, design philosophy, concept development and critical details of the cable-stayed option for this new bridge.