Seismic Response Analysis Of Railway Continuous Girder Bridges Considering Different Support And Constraint Systems

The support constraint system is a weak part of the seismic performance of the bridge structure system.Summarize the seismic damage of the continuous beam bridge of the railway.It can be found that the seismic damage of the support constraint system is very common.The support is an important part of the support restraint system.The failure of the support restraint system generally begins with the bearing damage.Therefore,seismic response analysis of railway continuous girder bridges based on different bearing forms is of great significance for studying the seismic response law of railway continuous girder bridges and optimizing the seismic design of railway continuous girder bridges.The simplified model,the double-fold line model and the hysteresis curve model are used to simulate the boundary conditions of the basin rubber bearing,and the SAP2000 finite element software is used to establish a(36+64+36)m railway continuous beam bridge based on the above three branches.The whole bridge analysis model of the seat mechanics model is used for seismic response analysis.By comparing the seismic response results of different models,it is found that the hysteresis curve model can best reflect the working state and mechanical properties of the basin rubber bearing under earthquake action.Summarize and analyze the mechanical model of lead rubber bearing at home and abroad,simplify the existing hysteresis model,refer to the American AASHTO specification and combine with China's "Code for Seismic Design of Railway Engineering" to obtain the calculation of mechanical parameters of lead rubber bearing.formula.Taking a(36+64+36)m railway continuous beam bridge as an example,the mechanical design parameters of the lead rubber bearing under different isolation periods(1.5T,2.0T,2.5T)are calculated.Through nonlinear time history analysis,Compare the seismic response results of bridges under different isolation periods to determine a reasonable isolation period.Comparing the seismic response results of a(36+64+36)m railway continuous beam bridge based on lead rubber bearing and basin rubber bearing,it is found that under the same conditions(the same design bearing capacity,the same site type,the same Seismic fortification intensity,etc.),the isolation effect of the lead rubber bearing in the bridge is obviously better than that of the basin rubber bearing.According to the mechanical parameters of the lead rubber bearing proposed in this paper,the nonlinear time-history analysis method is used to analyze the seismic isolation effect of the continuous beam bridge under different seismic conditions,different seismic intensities and different yield ratios.Figure34;Table37;Reference 56.