Abstract:Abstract : Research purposes : The selection of seismic design metliod for intercity railway bridges under frequent and rare earthquake,has a significant influence on safety of bridge structure. In order to study the characteristics of different seismic calculation methods for intercity railway continuous girder bridges,and determine the method used in different calculation phases, taking a Jinzhou - Puwan intercity railway continuous bridge of Dalian as the engineering background,this paper firstly introduces the calculation process of railway code simplified method,response spectrum method,elastic and elastic - plastic time - history analysis method. Furthierly, the seismic analysis of intercity railway continuous bridge under frequent and rare earthquake by using three analysis method has been conducted. Finally,the results of the top displacement,the bending moment and the shear force of piers are compared. Research conclusions :( 1 ) For continuous bridge, when it comes to longitudinal seismic effect under frequent earthquake excitation,there is little difference among railway code simplified method,response spectrum method and elastic time - history analysis. ( 2 ) When considering the horizontal earthquakeseismic effect under frequent earthquake,response spectrum method and elastic time - history analysis are preferred $ using railway code simplified metliod to be dangerous. (3) Faced with rare earthquake,elastic - plastic time - history analysis method is more reasonable and economical. (4) Faced with rare earthquake,using railway code simplified method or response spectrum method results distortion,will seriously enlarge the pier bottom bending moment and increase the amount of reinforcement. (5 ) The research results of t!iis paper have some guidance and reference for the seismic design of continuous girder bridges.