Seismic Response Research And Damping Control Of Large Span Continuous Beam Bridge

Long span continuous beam bridges are widely used in China's railway projects.Their spanning capacity is large,costs are low and structures are stable.China is an earthquakeprone country,in which earthquakes attacking vast areas have caused severe injuries and damages of the bridge.So it is necessary to study the seismic response and the technology of seismic reduction and isolation.This paper is based on the Min jiang river bridge.By using MIDAS/CIVIL to establish a three-dimensional finite element model,The response spectrum analysis,time history analysis,the analysis of traveling wave effect are carried out on the bridge and the technology of seismic reduction and isolation is studied.Some important conclusions are as follows:1?Comparing two models,pile-soil interaction and the fixed piers' bottom,by response spectrum analysis.The response result of pile-soil interaction model was smaller.Meanwhile,comparing the pile-soil interaction model with the three norms of China,Europe,USA by response spectrum analysis,the results indicated that the three specifications were close,and China's specification was the smallest.2?Conducting the analysis of the time history and comparing the results to the reaction spectrum.The analysis results of time histories were slightly less the reaction spectrum.3?Conducting the analysis of the traveling wave effect while considering the influences of wave velocity,pier height and traveling wave direction on the results.When the apparent wave velocity increased,the response result increased gradually and ended to have a consistent motivation tendency.The higher the pier height was,the smaller the stiffness,as well as the response.At the same time,The internal force of the pier became larger when it was near the source while that of far distances was smaller.4?Comparing with the three damping schemes of viscous dampers,speed lockers and friction pendulum supports,the damping effect of the friction pendulum support scheme was the best,yet the speed locking scheme was more economical.