【摘要】 和直线桥梁相比，弯桥在地震作用下的受力情况更加复杂。以三跨小半径预应力弯桥为工程背景，考虑土和结构相互作用，建立桥梁有限元模型，通过非线性动力时程分析，研究其在地震作用下的易损性。易损性分析中，采用位移延性比作为桥墩损伤指标，建立桥梁在不同损伤程度下的失效概率曲线。分析结果表明：随着地震动峰值加速度的增大，当地震强度大于某一初始值时，桥梁不同损伤程度的超越概率也随之增大。相同地震强度下，考虑桩土作用下，桥梁的损伤概率大于不考虑桩土相互作用下的损伤概率，因此对弯桥结构要考虑桩土相互作用的影响。研究成果可为弯桥抗震设计提供理论以及方法基础。更多还原

【Abstract】 Compared with a straight bridge, the stress of a curved bridge under earthquake is more complex. Taking a three-span small radius Prestressed Curved Bridge as the engineering background, considering the soil-structure interaction, the finite element model of the bridge is established, and seismic fragility analysis is conducted to compute the failure of the bridge through nonlinear dynamic time history analysis. In the fragility analysis, the displacement ductility ratio is used as a damage index to establish the probability curve of the bridge under different damage degrees. The results show that: with the increase of peak ground acceleration, when the seismic intensity is greater than a certain initial value, the probability of failure at different damage degrees of piers also increases. Under the same seismic intensity, the damage probability of the bridge considering the pile-soil interaction is greater than that without considering the pile-soil interaction. Therefore, the influence of pile-soil interaction should be considered for the curved bridge system. The results can provide a theoretical and methodological basis for the seismic design of curved bridges.更多还原