Study On Seismic Isolation Of Railway Simple Supported Beam Bridge In High Seismic Intensity Region

The bearings and piers are the vulnerable parts of the railway simple supported bridges under the earthquake. With respect to the pier, The bearing damaged in earthquake more easily repaired. Ordinary railway simply supported bridge is appropriate to the isolation bearing since its small basic natural vibration period. For simply supported beam bridge with isolation bearing, it will increase the risk of adjacent beams collision and unseating of superstructure, so it needs to have the corresponding beam falling prevention device. The influence of track system, collapse-proof device and earthquake impact on seismic response of railway isolated simply supported beam bridge is studied by combine with experimental way and numerical analysis method.the main research work is as follows:(1) The seismic damage characteristics of railway bridges are introduced, the seismic isolation technology and the development status of the Collapse-proof system are introduced, and the related research progress and deficiency at home and abroad are presented.(2) The model for the analysis of seismic response of multi span railway simply supported isolated bridges are discussed. Given the reduction method for the simulation of bearings and the various components of the bridge, the paper presents the rail, sleeper, ballast and subsequent structure simulation and the key parameters of the selection.(3) A finite element model is built based on the finite element model of a typical multi span railway isolated simply supported beam, and the influence of the track constraint on seismic response is studied.(4) A unseating prevention devices is proposed and the experimental research on the mechanics model. The numerical analysis method is proposed to study unseating prevention devices on the seismic response of the isolated railway simply supported bridge. And the unseating prevention device stiffness and initial gap on the influences of seismic response are studied.(5) Build a model include track restraint, isolation bearing, unseating prevention devices and consider the seismic pounding effects of seismic response. And studying the seismic response of isolated railway simply supported bridge by numerical analysis method.