摘要
采用概率性地震需求分析方法,建立了汶川地区典型简支梁桥的分析型地震易损性模型。基于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,抽样并生成一系列桥梁的有限元模型样本。利用汶川地震实测地震波对所建立的桥梁有限元模型进行非线性动力时程分析,并记录每一组分析中桥梁构件的地震峰值响应,通过回归分析建立地震动强度和桥梁构件地震需求之间的关系。在确定桥梁不同损伤状态对应的构件极限状态后,基于对数正态分布假设生成不同损伤状态对应的地震易损性曲线,最后基于可靠度理论计算得到桥梁系统易损性的上下确界。生成的地震易损性曲线可以进一步用于地震风险评估和震后加固优先级决策。
Analytical seismic vulnerability model of typically simply supported girder bridge was developed using the probabilistic seismic demand analysis approach. Based on collected data of damaged bridges from the 2008 Wenchuan Earthquake, a set of finite element model samples of bridges were produced by considering uncertainties with bridge parameters. Nonlinear dynamic transient analysis was preformed using the Wenchuan Earthquake ground motions, in which seismic peak responses of bridge components were recorded. By using the regression analysis method, a relationship between the ground motion intensity and components seismic demand is established. Once the limit states of bridge components at each bridge damage state were determined, seismic fragility curves were generated based on the logarithmic normal distribution assumption. Finally, by adopting the reliability theory and calculation, the lower and upper bounds of bridge system vulnerability were obtained. The generated seismic fragility curves can be used for seismic risk assessment and bridge retrofit prioritization.
出处
《工程力学》
EI
CSCD
北大核心
2013年第5期165-171,187,共8页
Engineering Mechanics
基金
地震行业科研专项项目"大震生命线工程灾害损失评估新技术研究"(201008005)
关键词
概率性地震需求模型
桥梁易损性
非线性动力时程分析
统计回归
对数正态分布
probabilistic seismic demand models
bridge vulnerability
nonlinear dynamic transient analysis
statistical regression
logarithmic normal distribution
