长周期结构地震反应的特点与反应谱  

Characteristics of earthquake response for long-period structures and response spectrum

作　　者：方小丹[1,2] 魏琏 周靖[2] 

机构地区：[1]华南理工大学建筑设计研究院,广东广州510640 [2]华南理工大学亚热带建筑科学国家重点实验室,广东广州510640 [3]深圳市力鹏建筑结构设计事务所,广东深圳518031

出　　处：《建筑结构学报》2014年第3期16-23,共8页Journal of Building Structures

基　　金：华南理工大学亚热带建筑科学国家重点实验室重点项目(2014ZA06)

摘　　要：讨论长周期结构地震反应的特点,分析我国建筑抗震设计规范中反应谱存在的主要缺陷。对反应谱进行人为的改变,会导致地震动特性的失真。我国规范反应谱的长周期段由于人为的调整,改变了地震动的统计特性,导致加速度反应谱对应的功率谱在长周期段异常,也导致长周期结构在地震作用下的计算位移偏大。抗震规范所规定的最小地震剪力系数仅与地震影响系数的最大值αmax相关,而与场地类别无关,有悖于软土场地上结构地震反应大于硬土场地上地震反应的一般规律。由加速度谱Sa、拟速度谱Sv和位移谱Sd之间的拟谱关系,给出了具有较长周期段(T延长至约10 s)的反应谱建议,可供规范修订时参考。工程算例表明,依据建议的反应谱进行结构的位移验算是可行的。The characteristics of earthquake response spectrum of China code for seismic response for long-period structures, and a few shortages existing in the design of buildings are analyzed. It can be clearly found that an artificial modification to response spectrum can result in the distortion of ground motion characteristics. The revision to the long- period segment in the response spectrum of China code can cause the change in the characteristics of ground motions, which results in an abnormal representation of power spectrum corresponding to acceleration spectrum. The analysis results show that the calculated displacements of long-period structures under earthquake action are over estimated. Minimum story seismic shear coeiticient described in the specification is only related to maximal earthquake influence coefficient （αmax）, but is not related to site classification, which is in conflict with the general rule that the earthquake responses of a structure at the soft-soil site are larger than those of a structure at the hard-soil site. According to the pseudo spectrum relations among acceleration spectrum, pseudo-velocity spectrum and displacement spectrum, a response spectrum pattern with longer-period segment （T is approximately extended to 10 s） is proposed, provide a according reference to specification revision. Engineering cases show that calculating the displacement response spectrum is feasible which can of structure

关 键 词：长周期结构 反应谱 位移谱 最小地震剪力系数 抗震设计 

分 类 号：TU318.1[建筑科学—结构工程]