框架结构基础隔震分析*
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（中国建筑科学研究院， 北京 100013）[摘要] 基础技术通过设置具有较小水平刚度和较大阻尼比的隔震层来控制地震震动向上部结构的传播，以达到减小结构地震反应的目的。基础隔震技术以其行之有效、简单方便、经济实用等优势，得到了工程界的认可与欢迎。本文选取一个六层框架结构隔震结构为研究对象，将其简化为单质点隔震模型并进行了理论分析；利用ETABS对某框架结构采用隔震支座前后进行了对比分析。结果表明：对于一般的多层隔震结构，隔震层的水平刚度越小，上部结构的加速度响应减小的越多；隔震层的阻尼比越小，上部结构的加速度响应减小的越多，但位移反应越大。与传统抗震结构相比，隔震结构的自振周期有较大程度的延长，侧移有较大幅度的增大，而隔震结构的层间侧移和楼层剪力有较大幅度的减小；结构的侧移主要集中在隔震层。[关键词] 基础隔震; ETABS; 框架结构; 反应谱分析中图分类号：TU375.4 文献标识码：A 文章编号：1002-848X(2013)S2-0395-04*中国建筑科学研究院青年科研基金：高抗震设防烈度区隔震结构应用研究（20122002331030114）项目资助。作者简介：栗增欣，硕士，工程师，Email：Lee_CABR@163.com。Analysis on frame structure of base isolationLi Zengxin, Dong Yu(China Academy of Building, Beijing 100013, China)Abstract: The technology of seismic isolation, by installing isolation layer between the base and the upper structure, is used to isolate seismic energy so that it can reduce the seismic response of the structure. In all kinds of seismic isolation measures, base isolation technology is accepted and popular in the field of engineering, because of the feature simplification, facility, efficacy and economy. In this thesis, a six-story framed structure, which is simplified as single-degree-of-freedom model, is studied. The dynamic equilibrium equation of the model is established and the solution is analyzed. In addition, the response of the non-isolation structure and the base-isolation structure of the frame structure are analyzed based on ETABS finite element analysis program. Analytic results indicated that the smaller horizontal stiffness of the isolation layer, the more acceleration decreases of upper structure. And the smaller damping ratio of the isolation layer, the more acceleration decreases of upper structure and the larger displacement. Compared with the traditional seismic structure, the inherent period of base-isolation structure is extended and the story displacement and the story sheer force of the upper structure significantly decrease. And the deformation is concentrated on isolation layer.Keywords: base isolation; ETABS; frame structure; spectrum analysis
