中文摘要：

为了研究近海隔震桥梁在全寿命周期内锈蚀损伤后的抗震性能,对近海隔震桥梁进行基于钢筋坑蚀效应的地震易损性分析。考虑海蚀环境中氯离子对钢筋混凝土结构的腐蚀作用,建立钢筋坑蚀效应概率模型,结合拉丁超立方抽样方法建立近海隔震桥梁在不同服役年限下的随机样本模型。选取墩顶漂移率和支座剪应变分别作为墩柱和隔震橡胶支座的损伤指标,采用Pushover分析计算墩柱的损伤指标限值,利用增量动力分析（IDA）方法对随机样本模型进行非线性时程分析,提取样本模型在不同地震动作用下的响应值,采用回归分析得到近海隔震桥梁构件的概率地震需求模型。通过基于传统可靠度概率的易损性分析方法构建桥梁墩柱和隔震橡胶支座在全寿命周期内的易损性曲线,并结合一阶可靠度理论得到近海隔震桥梁在全寿命周期内的整体易损性曲线,评估其在全寿命周期内的抗震性能。结果表明：氯离子的腐蚀会导致桥梁墩柱的抗震性能不断降低,各构件达到不同极限破坏状态的超越概率逐渐变大,结构整体易损性曲线超越概率逐渐增大;相比于初始服役时,经过钢筋锈蚀80年后,严重破坏、完全破坏状态时结构的超越概率上限值增幅分别可达12%、10%,而超越概率下限值相比于初始服役增幅分别达到14%、12%。

英文摘要：

In order to research the whole seismic performance of corrosive offshore isolated bridge after corrosion damage, seismic fragility analysis was carried out on the offshore isolated bridge based on the steel pitting corrosion effect. The probability model of steel pitting corrosion effect was established through considering the corrosion effect of chlorine ion on reinforced concrete structure under the marine environment, and the random sampling model of the bridges with different service years was established based on the Latin hypercube sampling method. Then, the pier top drift rate and the bearing shear strain were selected as the damage index of the pier and isolated rubber bearing respectively, and the damage index limit of pier was analyzed and calculated by Pushover method. The response values of the sampling model under differentseismic actions were extracted by carrying incremental dynamic analysis （IDA） method. out the nonlinear time history analysis using The probabilistic seismic demand models of the bridge components were obtained through the regression analysis. Combining the fragility curves of the pier and isolated rubber bearing in a whole life cycle based on the traditional reliability probability with the first order reliability theory, the whole fragility curve of offshore seismic isolated bridge under the whole life cycle was obtained and the seismic performance of the bridge in whole life cycle was also evaluated. The results show that because of corrosion effect of chlorine ion, the seismic performance of bridge pier is constantly decreased, the exceedance probabilities of components under different failure limit states are gradually increased, and the exceedance probabilities of fragility curves for the whole structure are also gradually increased. Compared to the initial service bridge, under severely damaged and totally destroyed conditions, the upper limit ranges of structural exceedance probabilities can increase 12% and 10%, and the lower limit ranges of the exceedance probabilitie