基于IDA-MC的桥梁地震风险概率评估方法  

Method and application of seismic risk probability analysis for large-long span bridge based on IDA-MC

作　　者：冯清海[1] 袁万城[2] 

机构地区：[1]中交公路规划设计院有限公司,北京100088 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《长安大学学报（自然科学版）》2010年第3期60-65,共6页Journal of Chang’an University(Natural Science Edition)

基　　金：国家自然科学基金项目(50778131);国家科技支撑计划项目(2006BAG04B01)

摘　　要：针对目前桥梁地震风险评估考虑的风险因素单一的不足,并为避免复杂的解析分析,引入增量动力分析方法(IDA)与蒙特卡罗(MC)分析方法相结合的技术,同步考虑地震危险性与桥梁结构在地震作用下的易损性,提出基于IDA-MC的特大桥梁地震风险概率评估方法。依据桥梁所在场地的地震烈度概率分布,通过蒙特卡罗抽样得到数量充足的地震烈度值,将其转换为对应的峰值加速度,并结合IDA分析,结果得到大量的结构响应;根据地震损伤准则判断桥梁结构的损伤指数,进而统计桥梁结构在不同损伤等级下的风险概率。以飘浮体系斜拉桥为例进行了演示,分析过程及结果充分体现了该方法的高效性与准确性,并对飘浮体系斜拉桥的地震风险概率规律进行了深入分析,分析结果将对桥梁的地震风险、运营管理提供有力的技术支撑。A method of seismic risk probability analysis for large-long span bridge based on incremental dynamic analysis（IDA） and Monte Carlo（MC） is presented,which takes the seismic hazard and seismic vulnerability into consideration synchronously,and avoids the complicated analytical solution.Firstly,seismic response of bridge is gained by IDA under plenty of seismic waves.Secondly,the distribution of earthquake intensity of the site is determined according the result of statistic.Then large number of earthquake intensity is generated by MC.Plenty of seismic response are gained according to the curve of seismic vulnerability and PGA transformed from the earthquake intensity.According to the seismic damage criterion,the seismic risk probability of bridge in different damage levels are gained.At the end,an example of floating cable-stayed bridge is analyzed,the analysis progress and results prove that this method is accurate and highly effective,and the results of risk analysis will be a technology support for the insure company whether and how it should be managed.1 tab,6 figs,10 refs.

关 键 词：桥梁工程 地震风险概率 特大桥梁 增量动力分析方法 蒙特卡罗分析方法 

分 类 号：U445.75[建筑科学—桥梁与隧道工程] TU352.1[交通运输工程—道路与铁道工程]