Seismic Response Analysis Of (48+80+80+48) M Continuous Beam Bridge

The prestressed concrete continuous girder bridge has the advantages of good overall performance,large structural rigidity,and small deformation.In addition,the design and construction technology of this type bridge are relatively mature,construction quality and construction period can be controlled,and the maintenance workload after bridge formation is small.These various advantages make this type bridge widely used in the construction of high-speed railways.The damage of the bridge facilities in the earthquake will not only cause huge economic losses,but also cause great difficulties for the subsequent rescue work.Therefore,it is particularly important to analyze the seismic response and seismic performance of the continuous beam bridge.The Baoying Bridge is a prestressed concrete continuous girder bridge with a total length of 257.3 m and a span of(48+2×80+48)m.This paper uses Midas Civil to establish a finite element calculation model.The earthquake response analysis of the bridge under the multiple earthquakes and rare earthquakes,the main work is as follows:(1)Applying the response spectrum method to analyze the seismic response under the action of multiple bridges in the direction of the bridge and the bridge in the presence or absence of train live load.The comparative analysis found that the impact of the train live load is very small.(2)Select three seismic wave records and use time-history analysis to analyze the seismic response under multi-field earthquakes and compare them with the response spectrum analysis results.(3)To study the seismic response of a continuous beam bridge under rare earthquakes,analyze the state of plastic hinge at the bottom of the pier and the displacement value at the pier top,and obtain the ductility value of piers based on the plastic rotation angle.(4)Comparing the bottom consolidation model and the pile-soil interaction model,the importance of the simulation of the pile foundation is explained by analyzing the relative changes of the displacement of the bottom of the two foundations and the internal force of the bottom of the foundation.(5)Considering the influence of different values of m in the same soil layer on the calculation results when using the “m” method to simulate the pile-soil interaction,it is found through comparison and analysis that the impact of different m values on the bridge piers is small.