The seismic fragility of a RC isolated continuous girder bridge is analyzed as a case, and the damage of bridge piers and isolated bearing components is considered. Meanwile, the incremental dynamic analysis of the bridge structure under different failure conditions is carried out, the randomness of the near ground motion and the structural parameters are taken into account. Based on the damage index of isolated bridge under different damage conditions, the seismic fragility curves of each member and the whole bridge structure of the isolated bridge are obtained according to the ability and the demand of the structure. The research shows that the safety control of the isolated continuous beam bridge structure is mainly affected by the seismic vulnerability of the isolated bearing, and the influence of bridge pier seismic fragility is relatively small. By applying the isolation scheme, the probability of the bridge structure with different damage state is greatly reduced, thus the seismic performance is improved. The results will provide a reference for future seismic damage prediction.

RC isolated continuous girder bridge, near-fault ground motions, seismic fragility analysis, damage index, isolated bearing

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