Study On The Influence Of Seismic Response By Vehicle Load On Small And Medium Span Beam Bridge

In this paper,the influence of vehicle load to seismic response of bridge is studied by combining theoretical analysis and numerical simulation.This article first summarizes and sums up the development process of highway bridge vibration,and the research status are discussed,the main purpose of the research is given in this paper.On the basis of previous studies,a suitable bridge and vehicle analysis model is established.Finally,with a highway span prestressed reinforced concrete continuous beam as an example,the establishment of the overall bridge model by finite element analysis software,discussed in detail the vehicle load size,vehicle speed,number of vehicle loads,stiffness and damping of vehicle suspension system etc.to influence of bridge dynamic response under earthquake load.In order to verify the accuracy of the model,this paper are used ANSYS and MIDAS/Civil finite element analysis software to establish the whole bridge model,then the dynamic characteristics are analyzed,and the results of the two analyses are compared.According to the comparison results,the dynamic characteristic analysis data of the two software were similar,the frequency and the period were different,and the vibration mode was basically the same.Then analyzed the effect of vehicle load on the seismic response of the bridge with ANSYS finite element software,through the simulation of different seismic loads and different span of bridge analysis,the following conclusions can be drawn: the number of vehicle load and vehicle had significant effects on the seismic response of the bridge,and the two was consistent,the influence curve with the increase of variables is first reduced and then increased,with the increase of load and displacement curve will have a minimum number of;the car speed on the vibration response of the bridge in the earthquake and non earthquake was the same,with the increased of girder vehicle speed midspan vertical displacement gradually decreased;automotive suspension system is affected by the stiffness and damping on the seismic response of the bridge,which can be ignored influence in the scope of engineering error.