In order to study the influence of different stress conditions in different construction stages of continuous rigid frame bridges on seismic vulnerability,the seismic damage performance of a long-span high-pier continuous rigid frame bridge is further analyzed.The models of each construction stage were established by software Midas/Civil,the obtained stress conditions of the construction stage were extracted,and inputted into the structural model established by software Abaqus.The internal forces obtained by the numerical simulation are verified to match those of the main beam and the main pier calculated by the equivalent load formula.Based on the standard response spectrum,10 groups of near-fault pulse ground motion records were generated,and two groups of models were input respectively.The incremental dynamic analysis method was used to analyze the time history of the two groups of models considering the force situation in the construction stage.The curvature ductility coefficient is the damage index to divide the damage state.Based on the theoretical vulnerability analysis method,the peak acceleration is used as the ground motion intensity index to obtain the seismic vulnerability curves of the main pier bottom,pier top and pier beam consolidation.The results show that the equivalent internal forces formulated by equivalent load method in each construction stage is in good agreement with those simulated by finite element method.Under the same ground motion intensity and different construction stages,the damage exceedance probabilities of the pier bottom,pier top and pier beam consolidation in each damage state increase with the increase of the cantilever length of the main beam;the damage probability of pier bottom and pier top will be underestimated without considering the force of bridge in construction stage,and the damage probability of pier beam consolidation will be overestimated.The underestimation of damage probability is the largest at the bottom of the pier along the longitudinal direction of the bridge,and the size of the underestimation is also directly related to the cantilever length of the main beam,which increases with the increase of the cantilever length.
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