主余震作用下地下结构增量损伤与抗震性能分析  

SEISMIC PERFORMANCE AND INCREMENTAL DAMAGE ANALYSIS OF UNDERGROUND STRUCTURES UNDER MAINSHOCK-AFTERSHOCK EARTHQUAKES

作　　者：王建宁 徐建[2] 潘鹏[1] 王国波 王鸿杰 WANG Jian-ning;XU Jian;PAN Peng;WANG Guo-bo;WANG Hong-jie(Department of Civil Engineering,Tsinghua University,Beijing 100084,China;China National Machinery Industry Co.,Ltd.,Beijing 100080,China;Beijing Materials Handling Research Institute Co.,Ltd.,Beijing 100007,China;College of Civil Engineering and Architecture,Wenzhou University,Wenzhou,Zhejiang 325035,China)

机构地区：[1]清华大学土木工程系,北京100084 [2]中国机械工业集团有限公司,北京100080 [3]北京起重运输机械设计研究院有限公司,北京100007 [4]温州大学建筑工程学院,浙江温州325035

出　　处：《工程力学》2023年第12期203-211,共9页Engineering Mechanics

基　　金：国家自然科学基金项目(52078386,51878529);国机集团重大科技专项项目(SINOMAST-ZDZX-2020-03);国机集团青年科技基金项目(QNJJ-PY-2022-02)。

摘　　要：强震过后短时间内发生的余震会对主震损伤结构产生重要影响,目前针对地下结构抗震性能的研究多是基于单次主震作用,对余震作用的认识有待进一步提高。为研究主余震作用下地下结构的性能劣化及增量损伤,以2层3跨地铁车站为原型建立土-地下结构相互作用模型,选取14次真实地震中的85组天然主震记录和对应的主余震序列为输入,对比研究了地下结构的地震响应特征。结果表明:考虑主余震作用时地下结构的地震损伤程度一般要比仅考虑主震作用时严重,但其增量幅度及扩展范围与主余震序列峰值加速度比ξ、地震动特性和主余震“极性”等因素有关;由于地下结构的损伤累计效应,在相近主余震峰值强度作用下(ξ≈1.0),地铁车站在余震时的层间位移反应较主震更大;当主震与余震的峰值加速度相差较大时(ξ≥1.4),余震对结构造成的附加损伤十分有限。Aftershocks occurring in a short time after a strong earthquake have an important impact on the structure damaged by the mainshock.Existing researches on seismic performance of underground structures are mainly based on the action of a single earthquake,and the understanding of the damage caused by aftershocks needs to be further improved.A soil-underground structure interaction model was established based on a typical two-story and three-span subway station to reveal the incremental damage and performance deterioration of the subway station subjected to mainshock-aftershock earthquakes.A set of 85 real mainshock records and mainshock-aftershock sequences from 14 real earthquakes were selected as inputs.Then,the seismic responses of underground structures were studied.The damage degree of the underground structure during the mainshockaftershock earthquakes is obviously more serious than that when only the mainshock is applied.The increment amplitude and extension range of the structure damage are related to such factors as the peak acceleration ratio ξ,the characteristics of ground motion and the polarity of the main aftershock.Due to the cumulative effect of structural damage,the interlayer displacement of subway stations caused by aftershock excitation is greater than that of the mainshock when the seismic intensity of the mainshock is similar to that of the aftershock(ξ≈1.0).When the intensity of the mainshock is much greater than that of the aftershock(ξ≥1.4),the additional damage caused by aftershock to the underground structure is limited.

关 键 词：地下结构 主余震 抗震性能 地震损伤 增量损伤 

分 类 号：TU43[建筑科学—岩土工程] TU93[建筑科学—土工工程]