主余震序列作用下屈曲约束支撑框架易损性分析  

Collapse Fragility Analysis of the Buckling-Restrained Braced Frame Subjected to Mainshock-Aftershock Sequences

作　　者：朱凯铭 郭玉荣[1,2] ZHU Kaiming;GUO Yurong(School of Civil Engineering,Hunan University,Changsha 410082,China;Key Laboratory of Building Safety and Energy,Ministry of Education,Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,长沙410082 [2]建筑安全与节能教育部重点实验室,长沙410082

出　　处：《结构工程师》2019年第6期109-115,共7页Structural Engineers

基　　金：国家自然科学基金(91315301,51468010)。

摘　　要：主震引发的多次强余震可能导致屈曲约束支撑(BRB)在地震作用下发生疲劳破坏。BRB突然失效可能使主震引起的微小损伤加剧,引发结构倒塌。因此,有必要考虑余震对BRB构件和BRBF结构的影响。通过增量动力方法,对考虑BRB疲劳性能的屈曲约束支撑框架(BRBF)进行易损性分析,对比了在单独主震和主余震序列作用下BRBF结构的地震易损性差异。结果表明,在高强度主余震序列作用下,BRBF结构的失效概率显著增加,对其性能要求更高。此外,分别以峰值层间位移角和残余峰值层间位移角作为需求参数指标,对比分析了BRBF结构在主余震序列作用下的易损性差别。结果表明,以残余峰值层间位移角为参数指标时,对结构性能要求更严格。The multiple aftershocks caused by the mainshock may lead to fatigue failure of the buckling-restrained brace(BRB)under earthquake.The sudden failure of the BRB may exacerbate the minor damage caused by the mainshock and even lead to structural collapse.Therefore,it is necessary to consider the impact of aftershocks on BRB components and BRBF structures.In this paper,using the incremental dynamic analysis method,the collapse fragility analysis of the buckling-restrained braced frame(BRBF)with BRB fatigue performance is carried out,and the seismic vulnerability of the structure under the action of the separate mainshock and main-aftershock sequences is compared.The results show that the failure probability of the BRBF structure increases significantly under the action of the high intensity main-aftershock sequences.In addition,the differences in vulnerability of BRBF structure are compared and analyzed under the action of main-aftershock sequences,using the peak drift and the residual peak drift as the damage indicators.The results show that more stringent requirements are imposed on the structural performance when the residual peak drift is used as the damage index.

关 键 词：主余震序列 屈曲约束支撑 易损性分析 峰值层间位移角 峰值残余层间位移角 

分 类 号：TU352.11[建筑科学—结构工程]