考虑SSI效应的基础隔震框架结构抗震性态水平分析  

Horizontal Analysis of Seismic Behavior of Base Isolated Frame Struc⁃ture Considering SSI Effect

作　　者：赵畅 于旭[2] 庄海洋 单志承[3] 吴晓飞 ZHAO Chang;YU Xu;ZHUANG Haiyang;SHAN Zhicheng;WU Xiaofei(Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 210009,China;Department of Civil Engineering,Nanjing Institute of Technology,Nanjing 211167,China;Nanjing Jiangning Economic Technology Development General Company,Nanjing 211167,China)

机构地区：[1]华东交通大学土木建筑学院,江西南昌330013 [2]南京工程学院建筑工程学院,江苏南京211167 [3]南京工业大学交通学院,江苏南京210009 [4]南京江宁经济技术开发集团有限公司,江苏南京211167

出　　处：《防灾减灾工程学报》2023年第5期1024-1034,共11页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金面上基金项目(51778282)资助。

摘　　要：目前针对于基础隔震结构的性态水平研究往往基于刚性地基假设,未考虑SSI效应对结构损伤的影响。因此,为研究柔性地基上小高宽比基础隔震结构的抗震性态水平,本文以拟建结构为背景,利用ABAQUS有限元软件建立该小高宽比基础隔震结构建筑物的有限元计算模型,依据相关规范规定,选取El‑Centro波、Kobe波和卧龙波,通过改变土体等效剪切波速设计扩展出5种场地,分析了地震动特性、场地条件以及输入地震动加速度峰值对该结构地震反应的影响规律,对该结构的损伤程度进行了统计分析。结果表明:柔性地基上随结构‑土体相对刚度比的增大,基础隔震结构的上部结构损伤和隔震层损伤均增大,且上部结构的损伤明显滞后于隔震支座损伤,IV场地在同等条件下损伤最严重;中长周期地震波对于隔震结构损伤影响较大;选取了层间位移角、隔震层位移作为抗震性态水平的量化指标,基于计算结果,本文初步给出了两类指标与结构‑土体相对刚度比的预测公式,提出了不同类别场地下小高宽比基础隔震结构的抗震性态水平划分及其破坏程度的物理描述。At present,research on the behavioral characteristics of base isolation structures often assumes a rigid foundation,neglecting the influence of Soil-Structure Interaction(SSI)on structural damage.Therefore,in order to study the seismic behavior level of small aspect ratio foundation isolation structures on flexible foundations,this paper takes the proposed structure as the background and uses ABAQUS finite element software to establish a finite element calculation model of the small aspect ratio foundation isolation structure building.We selected El-Centro wave,Kobe wave,and Wolong wave and designed five different site conditions according to relevant specifications.These conditions were created by varying the equivalent shear wave velocity of the soil.The influence of seismic characteristics,site conditions,and input seismic acceleration peak on the seismic response of the structure was analyzed,and the degree of damage to the structure was statistically analyzed.The results demonstrate that as the relative stiffness ratio between the structure and the soil on a flexible foundation increases,damage to the superstructure and isolation layer of base isolation structures also increases.Furthermore,under the same conditions,site IV experiences the most severe damage;Medium to long-period seismic waves have a substantial impact on the damage sustained by isolated structures.Quantitative indices for assessing seismic behavior levels were chosen as the inter-story displacement angle and isolation layer displacement.Based on the calculation results,this paper presents preliminary prediction formulas for both types of indices,the relative stiffness ratio between the structure and the soil,and proposes a classification system for seismic behavior levels.Additionally,it provides a physical description of the degree of damage to small aspect ratio isolation structures under various site conditions.

关 键 词：柔性地基 隔震结构 性态水平 损伤指数 量化指标 

分 类 号：TU352.1[建筑科学—结构工程] TU435