中文摘要：

采用扩展增量动力分析方法，建立了汶川地区典型简支梁桥的分析型地震易损性模型。依据汶川地震桥梁震后调查资料，评估了桥梁结构参数的不确定性，通过抽样并建立一系列桥梁的有限元模型样本。将汶川地震实测地震波调幅至不同的地震动强度，对每一级地震动强度下对不同样本进行非线性动力时程分析，记录桥梁各构件对应的地震峰值响应并绘制成IDA曲线。基于EDP准则和IM准则2种不同方法，分别计算得到不同地震动强度下桥梁发生各损伤状态的离散概率数据点，采用最小二乘法回归得到不同损伤状态对应的桥梁构件和系统地震易损性曲线。生成的地震易损性曲线可以进一步用于交通网络系统的地震风险评估和震后加固优先级决策。

英文摘要：

The analytical seismic vulnerability model of typical simply supported girder bridge in Wenchuan area was developed using the extended incremental dynamic analysis approach. Based on the collected data of bridge damage in 2008 Wenchuan Earthquake, the uncertainty of bridge parameters was analyzed and a set of finite element model samples of bridges were produced and a set of finite element model samples of bridges was produced by sample analysis. The Wenchuan Earthquake ground motions were scaled to different intensity intensities, in which seismic peak responses of each bridge components were recorded, and the nonlinear dynamic transient analysis of different samples under each intensity level were preformed, in which seismic peak responses of each bridge components were recorded and the IDA curves were developed. By employing two approaches based on EDP-criterion and IM-criterion, the discrete probabilistic data points of each bridge damage state under different intensities were calculated, and the seismic vulnerability curves of bridge components and system in each bridge damage state were generated by using the least squares regression. The generated seismic vulnerability curves could be used for seismic risk assessment of transport network system and bridge retrofit prioritization.