隔震层位置对隔震结构地震响应影响分析

SEISMIC RESPONSE ANALYSIS OF ISOLATION STRUCTURES WITH ISOLATION LAYER POSITION

以一栋地下一层地上三层框架结构为例,根据隔震层位置分别建立地下室地面以下的基础隔震、地下室顶板下部隔震以及非隔震结构模型。运用ETABS软件进行反应谱和时程分析,计算结构在地震作用下的基本周期、楼层剪力、层间位移,并与非隔震结构进行对比,得到隔震层位置变化时结构的地震响应。对比得知,结构采用隔震技术后结构周期较非隔震结构延长了4.5~5倍,当隔震层设置在地下室地面以下时,周期延长更多;采用隔震技术后结构的层间剪力和层间位移均有明显减小;隔震层位置变化对上部结构层间剪力影响较小,但对一层层间位移有显著影响。在工程设计时可根据工程实际的特点选择更适合隔震方式。

Take a frame structure with3 levels on the ground and one level underground as an example,based on the location of the isolation layer,the base isolation,the bottom isolation of the basement and the non-isolation structure model were established respectively. The response spectrum andtime history analysis were carried out by using ETABS software. The basic period,floor shear force andinterstory displacement of the structure under earthquake action are calculated,and compared with thenon-isolated structure,the seismic response of the structure is obtained when the isolation layer position changes.. The comparison of isolated structure period extended to 4.5~5 times,the isolation layer isset in the basement below ground,prolong the period of isolation structure more;the interlayer shear isobviously reduced,two kinds of isolation layer layout,has little effect on shear layer,so it can be selected more suitable for structure＇s isolation according to the convenience.