非平稳地震激励下结构动力可靠性方法对比研究  

Comparative Study on Structural Dynamic Reliability Methods under Non-stationary Seismic Excitations

作　　者：唐和生[1,2] 郭雪媛 薛松涛[1] TANG Hesheng;GUO Xueyuan;XUE Songtao(Department of Disaster Mitigation for Structures,Tongji University,Shanghai 200092,China;State Key Laboratory of Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学结构防灾减灾工程系,上海200092 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《结构工程师》2020年第4期46-51,共6页Structural Engineers

基　　金：科技部国家重点实验室基础研究资助项目(SLDRCE2019-B-02);上海市自然科学基金(17ZR1431900)。

摘　　要：针对结构在非平稳随机激励下的动力可靠性问题,基于首次超越理论,现有的动力可靠性计算方法分为两类:基于跨越率的方法与基于极值的方法。基于跨越率的方法将动力可靠性表示为跨越率的函数,并采用虚拟激励法对非平稳随机激励下结构随机响应进行计算;而基于极值的方法的通过对响应极值的不确定性进行量化,采用子集模拟获得响应极值的概率分布来估计动力可靠性。通过数值算例,对比研究了两种方法在非平稳随机过程频谱特征和响应阈值两种因素变化下的计算精度,结果表明,基于跨越率的方法受到显著影响,而基于极值的方法始终保持较高的计算精度。Based on the first-passage theory,the existing structural dynamic reliability analysis methods are divided into two classes:the out-crossing rate based methods and the extreme value based methods.The outcrossing rate methods are based on the Rice formula.The dynamic reliability is expressed as the function of outcrossing rate and the structural response is calculated by the pseudo excitation method.On the other hand,the uncertainty quantification of extreme value of the structural response by the subset simulation is the key to the extreme value based methods.The probability distribution of the extreme value is used to estimate the dynamic reliability.The numerical example is utilized to investigate the accuracy of the two methods under the influence of spectral characteristics of non-stationary random processes and response thresholds.The results indicate that the accuracy of the out-crossing rate based method is significantly affected,and the extreme value based method shows better accuracy.

关 键 词：非平稳随机激励 动力可靠性 首次超越 虚拟激励法 子集模拟 

分 类 号：TU311.3[建筑科学—结构工程]