The Seismic Response Research On The Continuous Rigid-structured Bridge With High Piers And Long-span

In recent years,with the rapid extension of highway construction in our countryto the mountain area,the span of bridges increasing,the pier has become more andmore higher.The span and pier height of many bridges are above the limit value of thecurrent seismic design codes. At present, the seismic design of continuous rigid framebridge with high pier and long-span is mainly refer to the regular bridge.Therefore, itis necessary to carry out research on seismic response of continuous rigid framebridge with high pier and long-span, in order to guide the seismic design of this kindof irregular bridge.(1)The dynamic characteristic of continuous rigid-structured bridge is analysedby finite element software Midas/Civil. The law of dynamic characteristics aresummarized by computing the basic frequency and vibration mode of the bridge. And16test models are built by changing the design of bridge structure parameters (spanratio, power of bottom curve, pier wall thickness, space between the double thin-wallpiers) to study its effect on the vibration characteristics of the structure by usingorthogonal experimental design.(2) The seismic responses of the16bridge models of the orthogonal test areanalysed in response spectrum method to determine the sensitivity of designparameters on continuous rigid frame bridge with high pier and long-span throughrange and variance analysis of the results.(3) By comparing and analyzing the displacements and internal forces of thebridge’s control sections under different seismic waves in the inconsistent excitationdynamic time-history analysis method, some useful conclusions are summed up. Themaximum value from the different seismic waves under the action of seismic responseresults is compared with the corresponding response spectrum to verify that theselected seismic wave accords with the requirements of the seismic design codes.(4)The impacts of the travelling-wave effect on Cheng Chuan River bridge areconsidered, the comparative analysis of the results under the traveling wave anduniform excitation is made, and the characters of the travelling-wave effect oncontinuous rigid-structured railway bridge are summed up. And the influence of pierwall thickness on seismic response of continuous rigid-frame bridge is studied.(5) Considering the material nonlinearity,the effect of the hight on seismicresponse of continuous rigid-frame bridge with high piers and long-span is studied inthe dynamic nonlinear method.