基于能量的主余震作用下RC框架损伤与震后性能评估  

Post-earthquake performance and damage evaluation of RC frames under mainshock-aftershock sequence based on energy concept

作　　者：陈涛 马高 CHEN Tao;MA Gao(College of Civil Engineering,Hunan University,Changsha 410082,China;Hunan Provincial Key Lab on Damage Diagnosis for Engineering Structures(Hunan University),Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]工程结构损伤诊断湖南省重点实验室(湖南大学),湖南长沙410082

出　　处：《地震工程与工程振动》2023年第4期161-170,共10页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(52278498,51878268);湖南省创新平台与人才计划项目(2021RC3041);湖南省自然科学基金项目(2020JJ4195)。

摘　　要：地震发生后,震损结构能否承受强余震是震害调查与灾后重建中的重要问题。因此,准确评估主余震造成的结构损伤以及评估主震后震损结构的剩余倒塌能力至关重要。采用基于能量的地震损伤指标对结构损伤进行评估,以能量谱作为工程需求参数,再通过引入震损结构模型对结构在主余震作用下的累积损伤进行评估,建立主余震作用下结构整体损伤评估理论框架。然后,基于I V损伤指数对主余震下的结构损伤进行量化,得到震损结构的倒塌能力曲线,并确定结构剩余承受强余震的能力。以6层3跨钢筋混凝土(reinforced concrete,RC)框架结构为例进行分析,结果表明:地震能量损伤指标法物理意义明确,可以从能量角度快速评价主余震下结构损伤;震损结构的剩余倒塌能力随着主震强度增加而逐渐降低;对于案例结构而言,主震下结构损伤小于0.32时可以认为震损结构是安全的可以承受强余震,介于0.32~0.52之间时,需要对震损结构加固修复,以保障余震安全。After an earthquake,whether the earthquake-damaged structures can withstand strong aftershocks is an important issue for post-earthquake reconnaissance and reconstruction.Therefore,it is of great significant to accurately evaluate the structural damage caused by the mainshock-aftershock sequence and the remaining collapse capacity of the damaged structures after the mainshock.In this paper,the energy-based seismic damage index was used to evaluate the structural damage,and the energy spectrum was utilized as the engineering demand parameter.The cumulative damage under the action of mainshock-aftershock sequence was evaluated by introducing an earthquake-damaged structure model.Then,a theoretical framework for the overall structural damage under the action of mainshock-aftershock sequence was established.Based on the I V damage index,the structural damage under the mainshock-aftershock sequence was quantified,and the collapse capacity curve of the damaged structure was obtained.The remaining capacity of the structure to withstand strong aftershocks was finally determined.In this paper,a 6-story 3-span reinforced concrete(RC)frame structure was taken as an example.The analysis results showed that the seismic energy index method had a clear physical meaning and can quickly evaluate the structural damage under the mainshock-aftershock sequence from the energy point of view.The remaining collapse capacity of the earthquake-damaged structure deceased with the increase in mainshock.For the case structure,when the structural damage under the mainshock was less than 0.32,it can be considered that the earthquake-damaged structure was safe and can withstand strong aftershocks.When the damage was between 0.32 and 0.52,the earthquake-damaged structure is needed to be retrofitted to ensure safety under aftershocks.

关 键 词：震损结构 地震能量损伤指标法 主余震序列 结构损伤评估 累积损伤 

分 类 号：TU375[建筑科学—结构工程]