ABSTRACT
ABSTRACT: Seismic retrofit designs of three cable-supported bridges in Tokyo, namely: Rainbow, Yokohama Bay and Tsurumi Fairway Bridges are described. The site-dependent far-field ground motion due to possible maximum credible earthquake is calculated using fault rupture model together with wave propagation technique. The nonlinear seismic response of the bridges including soil-structure interaction is computed, and it is found that all three bridges may suffer considerable damage. For the structural elements that receive severe damage, careful retrofit design is conducted. Considering that large bridges are complex structural systems, increase of the structural redundancy and fail-safe concept is emphasized in the retrofit design.
