Seismic Study On Double Column Pier Of Highway Continuous Beam Bridge

China is a country with high frequency and intensity of earthquake,the seismic design of bridge has been paid more and more attention.Combined with the investigation and study of bridge damages in Wen Chuan earthquake,this paper analyzed the damage reason of the continuous beam bridge,selected stress more reasonable and less damage of double column continuous girder bridge as the research object,and then made the seismic research of double column pier from the bridge seismic design theory,seismic response analysis method and seismic performance influence factors.Firstly,the paper systematically introduced bridge seismic ductility design theory,explained the basic concepts of ductility,explored the ductility seismic design method and put forward suggestions for rational parameters by means of the comparative analysis of the domestic and foreign design specifications.Secondly,the paper introduced the development process of the seismic response analysis methods,explained the basic principle of the elastic response spectrum method,elastic-plastic analysis of response spectrum method and dynamic time history analysis method,derived their dynamic equation and relevant parameters,and then solved the seismic response results.The basic principle and solving method of the static elastic-plastic analysis method are explored,and the modal pushover method is used to solve the structural seismic response and the limit displacement of the structure.Thirdly,the paper used the Midas civil software to establish the finite element model,and then calculated the seismic response of the bridge by means of the elastic response spectrum method,the elastic-plastic response spectrum method,elastic-plastic static analysis method and dynamic time history method,comparatively analyzed the calculation results,evaluated advantages and disadvantages of the different methods,so as to select the reasonable seismic response analysis method.Finally,the paper used the elastic and plastic static analysis method to study the influence factors on seismic behavior of double column pier.Through changing the pier's shear span ratio,axial pressure ratio,stirrup ratio and longitudinal reinforcement ratio,I calculated pier bending moment,shear force and displacement capacity requirements,and analyzed these factors on seismic performance,then put forward the reasonable range of seismic influence factors.