The objective of this study is to propose a framework for evaluating the seismic fragility of bridge systems analytically taking into account correlations between component behaviors. To include coupled effects of component behaviors on system behavior, the second-order reliability approach is adopted. The damage states of the combined fragility are proposed based on system behavior characteristics obtained by pushover analyses. The characteristics of the combined fragility information of two bridge models are illustrated using probabilistic seismic demand analysis based on the time history analysis results from several earthquake excitations. The fragility curves obtained from the second-order reliability model are compared with the first-order reliability model. It is shown that the proposed framework can provide more detailed fragility information rather than only providing bounds of system fragility as in the first-order reliability-based approach.

中文翻译：

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考虑构件损伤相关性的桥梁抗震脆性评估框架

本研究的目的是提出一个框架，用于评估桥梁系统的地震脆弱性，分析考虑组件行为之间的相关性。为了包括组件行为对系统行为的耦合影响，采用二阶可靠性方法。基于pushover分析得到的系统行为特征，提出了组合脆性的损伤状态。基于多次地震激发的时程分析结果，使用概率地震需求分析说明了两种桥梁模型的组合脆弱性信息的特征。将二阶可靠性模型得到的脆弱性曲线与一阶可靠性模型进行比较。