Nonlinear time-history analysis of seismic response of a long-span cable-stayed bridge

Based on the theory of finite element analysis and with reference to one long-span cable-stayed bridge,the bridge model is established by the software of ANSYS.The seismic response of the bridge under the El Centro wave is obtained by time-history analysis method,the El Centro wave is adjusted,and is inputted from longitudinal,transverse and vertical direction,respectively.The computed results indicate that the internal force and displacement are influenced obviously by the geometric nonlinear effect more than the linear effect.For the internal force and displacement of the girder and tower under the seismic ground motion,the effect and the rules of the seismic responses are different from nonlinear geometric effect.The results also show that the bridge has a good seismic performance,and the bridge design is not controlled by the seismic load.As a result,the geometric nonlinear effect must be considered in the seismic response analysis of the cable-stayed bridges.