全概率理论斜拉桥地震风险分析  

Seismic risk analysis for cable-stayed bridges based on total probability theorem

作　　者：钟剑[1] 万华平 任伟新[1] 袁万城[2] ZHONG Jian;WAN Hua-ping;REN Wei-xin;YUAN Wan-cheng(School of Civil and Hydraulic Engineering,Hefei University of Technology,Hefei 230009,China;State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]合肥工业大学土木与水利工程学院,安徽合肥230009 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《振动工程学报》2018年第4期654-661,共8页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51608161;51278163;51508144);安徽省自然科学基金资助项目(1608085QE118);中央高校基本科研业务费专项资金资助项目(JZ2016HGBZ0786);博士后面上基金资助项目(2016M602007)

摘　　要：桥梁的地震风险分析涉及到场地地震危险性分析、概率性的地震需求分析以及概率性的抗震能力分析等阶段。鉴于各阶段存在不确定性,因此有必要在桥梁的地震风险分析中考虑各阶段不确定性,具体是基于全概率方法推导出斜拉桥不同性能水平下的地震风险的解析解。以迫龙沟大跨度斜拉桥为工程背景,建立OpenSEES非线性有限元模型,从PEER地震库选择100条符合场地条件的地震波来考虑地震动的不确定性,通过非线性时程分析建立概率需求地震模型,讨论了地震需求的不确定性和性能水平的不确定性对斜拉桥地震风险的影响。研究结果表明,忽略不确定性因素的影响会大大地低估了斜拉桥的地震风险。The seismic risk analysis comprises seismic hazard analysis,probabilistic seismic demand analysis and probabilistic capacity analysis.There exist the uncertainties in each part.Therefore,the closed-form formula of the seismic risk with different performance levels is derived in this research based on total probability theory accounting for the uncertainties during the seismic risk analysis.Taking a long span cable-stayed bridge as an engineering background,a nonlinear finite element model is established by OpenSEES.100 ground motion records are chosen from PEER based on the site condition of the bridge to account for the uncertainties of earthquake.Then,the nonlinear time analysis is conducted to establish the probabilistic seismic demand model.The influence of uncertainties of the seismic demand and the performance level threshold on the seismic risk is discussed,which shows that the seismic risk would be greatly underestimated when ignoring the uncertainties.

关 键 词：斜拉桥 抗震设计 不确定性 地震危险性分析 全概率 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]