基于IDA的主余震序列作用下RC框架易损性分析与生命周期费用评估

Fragility analysis and life cycle cost assessment of RC frame under mainshock-aftershock seismic sequences through IDA

本文基于IDA方法对一实际6层钢筋混凝土框架进行易损性分析,结果表明结构在主余震协同作用下的失效概率会显著增加,需要在设计中考虑余震。进一步假定设计时采用增加钢支撑的方式应对主余震序列型地震动,研究了加撑后框架结构的易损性并对两类结构在生命周期内的总费用进行了评估。评估结果表明,在设计中采用增加钢支撑的方式来应对主余震序列型地震动虽然会增加结构的初始投资,但会降低结构整个生命周期内的总费用。

In this paper,IDA is used to conduct the fragility analysis of an actual 6-floor RC frame. The conclusion is drawn that the failure probabilities of structure would be significantly increased under the mainshock-aftershock seismic sequences. Therefore,the effect of the aftershock should be considered at the structural design stage. Additional steel braces are then taken as a measure to resist manishock-aftershock attack,and the fragility analysis is carried out on the updated structure. After that,the life cycle costs of the original and updated structure are compared. The results demonstrate that additional steel braces would increase the initial investment but decrease the whole cost during the life cycle time with consideration of mainshock-aftershock earthquake sequence.