Analysis of Seismic Response of Long Span,HighRise Pier and Short Radius Curved Hybrid Bridge of Rigid Frame and Continuous Girder

To study the seismic response of the long span,high-rise pier and short radius curved hybrid bridge of rigid frame and continuous girder,a railway bridge of the same structural type with span arrangement(40+6×80+40) m was cited as an example and analyzed.The ANSYS was used to set up the finite element model for the whole bridge of the bridge,the dynamic properties of the bridge were calculated and the internal forces and displacement under the seismic action were analyzed,using the response spectrum method and the time-history analysis method.The results of the analysis reveal that the increase of rigidity of the bridge piers and the application of rigid fixity of the piers and girder can improve the integrality of the curved hybrid bridge of rigid frame and continuous girder and are advantageous to the seismic resistance.In comprehensive consideration of the seismic response(e.g.displacement and moment),the worst seismic wave excitation angles of the bridge of such type are 0°and 90°(respectively corresponding to the longitudinal and transverse directions of the bridge).The increase of the transverse rigidity can decrease the displacement of the bridge in the transverse direction and the increase of the sectional areas of footings of the piers can reduce the seismic response of the bridge under the horizontal seismic action.In general,the transverse displacement and out-of-plane moment of the bridge under the seismic wave excitation in the transverse direction are the maximum while the longitudinal displacement and in-plane moment of the bridge under the excitation in the longitudinal direction are also the maximum.