基于持时-条件谱双准则选取地震动的RC框架结构地震损伤分析  

Seismic damage analysis of RC frame structures based on ground motion selection using double criteria of duration and conditional spectrum

作　　者：韩建平[1,2] 王宁[1,2] 黄小宁 Han Jianping;Wang Ning;Huang Xiaoning(Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province,Lanzhou Umiversity of Technology,Lanzhou 730050,China;Institute of Earthquake Protection and Disaster Mitigation,Lanzhou University of Technology,Lanzhou 730050,China;Qinghai University,Xining 810016,China)

机构地区：[1]兰州理工大学甘肃省土木工程防灾减灾重点实验室,甘肃兰州730050 [2]兰州理工大学防震减灾研究所,甘肃兰州730050 [3]青海大学,青海西宁810016

出　　处：《土木工程学报》2024年第6期101-115,共15页China Civil Engineering Journal

基　　金：国家自然科学基金(51578273);教育部长江学者和创新团队发展计划(IRT_17R51)。

摘　　要：采用持时-条件谱双准则选择地震动记录,以损伤指数为性能指标对结构进行地震损伤分析。首先,根据选择的性能目标,确定不同水准地震加速度反应谱S_(a)(T_(1),5%),通过概率地震危险解聚分析确定不同水准S_(a)(T_(1),5%)对应的设计震级和设计震中距,结合地震动重要持时预测模型,通过调节持时预测模型标准差系数的范围,构建满足重要持时要求的待选地震动记录库。其次,建立地震动条件谱,从待选地震动记录库中选择地震动,并验证持时-条件谱双准则选择地震动记录方法的有效性。最后,以选择地震动为输入对一钢筋混凝土框架结构进行增量动力分析,结合考虑构件重要性系数的变形-滞回耗能双参数损伤模型,以损伤指数为性能指标分析结构的地震损伤。研究表明,与仅利用条件谱作为目标谱选择地震动相比,基于持时-条件谱双准则的地震动选取方法对结构变形和滞回耗能响应的离散性均可控且效果良好;对结构进行地震损伤分析发现,滞回耗能引起损伤的占比随S_(a)(T_(1),5%)的增大明显增大,同时滞回耗能可使结构的损伤模式发生改变,在地震损伤分析中不可忽略。Ground motion records were selected considering both the duration and conditional spectrum(CS),and then seismic damage analysis was performed with the damage factors taken as performance indexes.Firstly,different levels of spectral acceleration,S_a(T_1,5%),were obtained based on the considered performance objectives.Design magnitude and design epicentral distance corresponding to S_a(T_1,5%)can be determined through probabilistic seismic hazard deaggregation analysis,which,along with ground motion duration prediction equation(GMDPE),can be used to establish the record database by adjusting standard deviation coefficient in GMDPE.The record database meets the requirements of the significant duration.CS was then generated,and based on it the finial ground motion records were selected from the aforementioned database.The validity of the proposed ground motion record selection approach was also verified.Finally,incremental dynamic analysis was conducted using the selected ground motions,and in combination with a dual-parameter damage model,the seismic damage of the case-study RC frame structure was evaluated.In this damage model,the importance coefficients of structural components are incorporated,and both the deformation and hysteretic energy are considered.The results indicate that the proposed selection approach is more efficient in controlling the discreteness of structural responses,including both the deformation and hysteretic energy,compared to the selection method with only CS taken as the target spectrum.Based on the seismic damage analysis of the structure,it is found that the proportion of damage caused by hysteretic energy increases markedly with the increase of S_a(T_1,5%),and the hysteretic energy can change the damage mode,which should not be ignored in seismic damage analysis.

关 键 词：地震动选择 条件谱 地震动持时 地震易损性 损伤指数 

分 类 号：TU352.1[建筑科学—结构工程]