P-Δ效应对基础隔震结构地震响应影响研究

摘要

隔震支座在地震作用过程中水平变形时,会对上部结构附加由于隔震支座P-Δ效应造成的弯矩.国内,关于隔震支座的P-Δ效应对基础隔震结构地震响应具体影响相关的研究,相对较少.采用PERFROM-3D软件,建立上部结构弹塑性的基础隔震结构模型,进行了考虑与不考虑隔震支座P-Δ效应的计算分析,对比了层剪力系数、 层间位移、 层倾覆弯矩、 加速度等地震响应.结果表明:隔震支座的P-Δ效应对基础隔震结构的底层层间位移响应及上部结构柱底转角位移造成一定影响,其它地震响应基本无差异.%Horizontal deformation of isolation bearings in the earthquake action produces additional moment on the upper structure of base isolated structure, which is caused by P-Δ effects of isolation bearings. In China, there are relatively few researches on the influence of P-Δeffects of isolation bearings on the seismic response of base isolated structure. Using PERFROM-3D software, a base isolation structure model considering plasticity of the upper structure is established to be analyze. Considering and unconsidering P-Δ effects of isolation bearings, seismic response of base isolated structure are compared, such as acceleration, storey drift, storey shear, storey overturning moment, etc. The results show that the storey drift of bottom layer and the bottom rotation displacement of the upper structure are affected by P-Δ effects of isolation bearing and other seismic response almost have no difference.