EVALUATION OF SEISMIC RESISTANCE CAPACITY FOR YIBIN YANGTZE RIVER CABLE-STAYED BRIDGE

A dynamic finite element model using a single-beam model has been adopted for Yibin Yangtze River cable-stayed bridge, to analyze its dynamic characteristic and seismic responses with considering the interaction between the pile and the soil as well as the effect of the pile group. The comparative analysis of the seismic response has been made by employing the response spectrum method and the time history analysis method. The analytical results show that the seismic resistance capacity of Yinbin bridge can satisfy the requirement; and the elastic cable system connecting the girder and the towers is appropriately designed for reducing the seismic response. However, the bridge seismic responses can be reduced by further loosening the stiffness or by applying the elastic cable together with the damping device system. It is suggested that the structural internal forces and deformations of long-span cable-stayed bridges should be analyzed by using both the response spectrum method and the time history analysis method, and the maximum values from these two methods should be used for the seismic design of bridges.