长周期地震动下软夹层地基的层间隔震结构振动台试验研究  

Shaking table test of inter-story isolation structure on a soft interlayer ground under long-period ground motion

作　　者：吴应雄[1] 陈劲杨 方泓杰 施建日 许立英[3] WU Ying-xiong;CHEN Jin-yang;FANG Hong-jie;SHI Jian-ri;XU Li-ying(College of Civil Engineering,Fuzhou University,Fuzhou 350108,China;Fujian Provincial Institute of Architectural Design and Research Co.,Ltd.,Fuzhou 350001,China;School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]福州大学土木工程学院,福建福州350108 [2]福建省建筑设计研究院有限公司,福建福州350001 [3]西南科技大学土木工程与建筑学院,四川绵阳621010

出　　处：《振动工程学报》2023年第2期345-356,共12页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51778149);中国地震局工程力学研究所基本科研业务专项资助项目(2021D03);福建省建设科技研究开发项目(2020,2022)。

摘　　要：长周期地震动易使隔震结构地震响应强烈,考虑土-结构相互作用(SSI效应)后隔震结构可能更不利。为探究长周期地震动下软弱夹层地基SSI效应对层间隔震结构的动力响应规律及减震性能的影响,开展刚性、软夹层地基上大底盘单塔楼层间隔震结构的数值模拟和振动台试验。结果表明:考虑SSI效应后结构的自振周期较刚性地基增大,但采用隔震技术后延长的周期倍数降低;软夹层地基对输入地震动具有明显放大和滤波效应,与地震动的峰值和频谱特性相关;SSI效应对层间隔震结构的地震响应以放大作用为主,对下部底盘和隔震层的影响较大;考虑SSI效应后长周期地震动下隔震结构的地震响应较普通地震动更为强烈,减震效果变差,特别是近场脉冲地震动下隔震层位移超限,体系发生失效破坏。Long-period ground motion is easy to cause strong seismic response of isolated structure,which may be more disadvanta⁃geous when considering soil-structure interaction(SSI effect).In order to explore the influence of the SSI effect of the weak inter⁃layer foundation under the long-term period of ground vibration on the dynamic response law and shock absorption performance of the layer interval vibration structure,the numerical simulation and vibration platform test of the single tower layer interval vibration structure of the large chassis on the rigid and soft interlayer foundation are carried out.The results show that the soft interlayer foun⁃dation has an obvious amplification and filtering effect on the input ground vibration,which is associated with the peak and spectral characteristics of the ground vibration.After considering SSI effect,the natural vibration period of the structure is larger than that of the rigid foundation,but the extended period multiple of the isolation technology is lower.The SSI effect enlarges the accelera⁃tion response to the lower chassis and the diaphragm,and may increase or decrease the acceleration response of the upper tower,depending on the type and intensity of the input seismic vibration.After considering the SSI effect,the seismic response of the iso⁃lation structure under long-period ground motions is stronger than that of ordinary ground motions,and the damping effect becomes worse.In particular,the displacement of the isolation layer under near-field impulse ground motions exceeds the limit,the damping effect is poor,and the system fails.

关 键 词：长周期地震动 层间隔震 SSI效应 软夹层地基 振动台试验 

分 类 号：TU352.12[建筑科学—结构工程] TU317.1