In order to study the seismic vulnerability of irregular long-span rigid frame continuous composite bridge under longitudinal and transverse earthquake ground motions

one certain western mountain long-span rigid frame continuous composite bridge with hollow thin-walled pier is taken as the research object.The analytical fiber model is established in light of the bridge configuration aided by OpenSees software.The incremental dynamic analysis（IDA）method is adopted to obtain the bridge structural seismic responses under 240 earthquake ground motion records

then the curvature envelopes for each pier under longitudinal and transverse earthquake ground motions are got.Moreover

the curvature and displacement are respectively regarded as the damage index of the piers and bearings to figure out the failure probabilities of different damage states

and the vulnerability curves are formed finally.The results show that the seismic vulnerability of piers are mainly influenced by the longitudinal earthquake ground motions and with the increase of the pier height

the damage probability decreases.The seismic vulnerability of the bearings is controlled by the transverse earthquake ground motions.The research results can provide references for seismic design of long-span rigid frame continuous composite bridges.