Seismic Performance-Based Design of Cable-Supported Bridges: State of Practice in the United States

Abstract

The concept of performance-based seismic design dates from the 1990s. Several complex bridges in seismic hazard zones were designed following this concept. The list includes but not limited to the New Carquinez Suspension Bridge, the New Tacoma Narrows Suspension Bridge, and the Gerald Desmond Bridge. This paper documents the fundamental issues that were considered in the seismic design of recent cable-supported bridges including the seismic performance-based criteria (PBDC). The paper also discusses how the local damage levels are employed through a deformation-based approach to achieve the global performance objectives of the bridge. The paper also explains the development procedure of spectrum compatible ground motions through probabilistic seismic hazard analysis. Issues such as foundation modeling, soil–structure interaction, and appropriate damping are also outlined. PBDC is an appropriate approach for the seismic assessment of this class of bridges, particularly if the damage is determined using a displacement-based assessment approach.