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为研究深水环境下连续刚构桥的概率性地震损伤特性,以中国西部某高速公路三跨深水连续刚构桥为对象,考虑桩-土动力相互作用和桥梁水中部分的动水效应,采用OpenSees软件建立其全桥非线性有限元模型.选取与规范设计谱相匹配的成组地震记录为输入,开展无水、水深12m、水深27m这3种工况下的全桥结构增量动力分析.以主跨左侧双壁墩为对象,采用概率地震需求分析方法计算16％、50％和84％这3种分位数水平的概率分位曲线,并生成不同损伤水平下的易损性曲线.结果表明:动水效应会延长结构的自振周期;桥墩各主要截面的曲率均随地震动峰值加速度PGA的增加而增大,墩底截面比墩顶以更高概率进入严重破坏、完全破坏阶段;双壁墩内侧墩壁截面出现同级损伤的概率大于外侧墩壁;随着水深增加,墩底截面曲率响应随之增大,各破坏等级的超越概率也相应增大,当PGA为0.6g时,3种水深下内侧墩底发生完全破坏的概率分别为28.1％、39.4％和67.6％.深水环境的存在会显著增大连续刚构桥在不同地震动水平下的破坏超越概率,应予以重视.“,”In order to investigate the probabilistic seismic damage characteristics of deep-water continuous rigid frame bridges,three-span continuous rigid frame bridge of an expressway in deep water was taken as an object.The nonlinear finite element model of the bridge was established by OpenSees software,and the influence of pile-soil dynamic interaction and hydrodynamic effect for the submerged parts were considered.With grouped earthquake records matched with the code spectrum as the excitation,incremental dynamic analysis (IDA) was conducted for the bridge structure,under three conditions of waterless environment as well as water depths of 12 m and 27 m respectively.Taken the left double-wall pier of the main span as the object,the fractile IDA curves at probability levels of 16％,50％ and 84％ and the fragility curves at different damage states were developed by probabilistic seismic demand analysis method.The results show that the natural vibration period of the bridge will be extended under the hydrodynamic effect.The curvature response of main sections increases with the increasing of the peak ground acceleration (PGA),and the bottom sections of the pier tends to enter the stage of “serious damage” and “complete destruction” with a higher probability than the top sections.In addition,the inside wall of the pier has greater exceedance probability than the outer wall at different damage levels.With the enlargement of water depth,the curvature of the bottom section increases and the exceedance probability under each damage state amplifies accordingly.When the PGA is 0.6g,the exceedance probabilities of “complete destruction” for the bottom section of the inside wall are 28.1％,39.4％ and 67.6％,respectively,under three kinds of water depths.The deep water environment will magnify significantly the damage exceedance probability for continuous rigid frame bridges under different seismic levels,and hence,more attention should be paid to it.