Seismic Response Analysis Of Zhengzhou-wanzhou High-speed Railway(36+3×72+36) M Continuous Beam Bridge

With the continuous construction of China's transportation infrastructure,the transportation capacity has been developed rapidly,especially the development of highspeed railway.Especially in the past decade,a large number of high-speed railways have been built and put into operation.Some lines and bridges account for more than 90% of the total length.Among them,prestressed concrete continuous girder bridges are widely used in high-speed railways due to their advantages of good overall performance,small deformation and stable operation.If there is a strong earthquake,bridges may be seriously damaged in the earthquake,leading to the interruption of transportation lifeline,thus hindering the transportation of disaster relief materials and threatening the safety of people's lives and properties.Therefore,it is necessary to study the seismic response of prestressed concrete continuous beam bridge.This paper takes Dongjin No.1(36+3×72+36)m continuous beam bridge of Zhengzhou-Wanzhou railway as the research object,uses Midas civil to establish the finite element model according to the construction drawing design of the joint bridge,and carries out the dynamic characteristics,frequent earthquake and rare earthquake simulation analysis of the model.The main research contents are as follows:(1)In this paper,two kinds of finite element models of continuous beam bridge are established.The dynamic characteristics of the bridge are analyzed by considering whether pile-soil interaction is a variable,and the influence degree of pile-soil interaction on the dynamic characteristics of the bridge is analyzed.(2)Under the condition of train load or not,the finite element model of continuous beam bridge is established,and the response analysis is carried out by response spectrum method.(3)Referring to the seismic records,seven seismic waves are selected according to the requirements of the code.Taking the train load or not as the variable,the finite element model is established to analyze the time history response along and across the bridge direction,and the results are compared with the results of response spectrum analysis.(4)The model of the plastic hinge at the bottom of the pier is established to study the response of the plastic hinge under the rare earthquake.The state of the plastic hinge at the bottom of the pier,the displacement at the top of each pier and the ductility coefficient of the displacement at the bottom of the pier are analyzed.The seismic response of the bridge under the limit earthquake is analyzed.