PERFORMANCE CHECK FOR STEEL SUPERSTRUCTURE IN THE SEISMIC DESIGN OF YOKOHAMA BAY BRIDGE

Seismic retrofitting is under way for the Yokohama Bay Bridge, Rainbow Bridge and Tsurumi Tsubasa Bridge, long-span cable-supported bridges on the metropolitan expressway. This paper presents the results of seismic performance check for the steel truss girder in the lower deck of a double-deck main girder and for the steel pylon of the Yokohama Bay Bridge, a long cable-stayed bridge. The steel through truss girder and steel pylon were modeled using three-dimensional shell elements because no empirical research results were available concerning their strength and nonlinearity. A pushover analysis was then conducted using as a seismic force the inertia force distribution at the maximum seismic response at the study damage position, for checking seismic performance of the superstructure.