In order to study the seismic isolation effect of friction pendulum bearings on simple-supported box girder bridges of high-speed railway,the simple-supported box girder bridges of 24 m,32 m and 40 m typical spans of high-speed railway are taken as the research objects.MIDAS/Civil finite element software was used to establish the models of traditional seismic system and seismic isolation system for nonlinear dynamic time-history analysis.The influence of bridge pier height,bridge span and peak ground motion acceleration(PGA)on the seismic response of simple-supported box girder bridges was studied.The results show that the pier height and cross-section form have a great influence on the damping rate of the internal force at the bottom of the pier and the displacement at the top of the pier,and the influence of the pier height is more obvious.The height of bridge pier and peak ground motion acceleration(PGA)have great influence on the displacement of FPB bearing,and the influence of PGA change is more obvious.The maximum influence of bridge span on damping ratio is 9％in pier height(5～20 m),but the overall variation of damping ratio is not changed.The influence of peak ground motion acceleration(PGA)on damping ratio is 1％～6％when the pier height is 5～45 m.Setting reasonable pier stiffness and section form for high-speed railway bridge can improve the damping effect of pier bottom internal force and pier top displacement.
维普
万方数据