基础隔震结构整体非线性动力响应分析研究

Global nonlinear dynamic response analysis on base isolated structure

为研究隔震结构在地震作用下的非线性响应规律,对某高层隔震剪力墙结构,分别考虑上部结构为弹性与弹塑性,进行中震和罕遇地震作用下的动力时程分析研究,同时分析整体弹塑性模型中保持楼板弹性假定对结构响应的影响.分析表明,考虑整体弹塑性作用的隔震结构减震系数减小,罕遇地震下层间位移角增大,顶点位移时程滞后于仅考虑支座非线性作用的分析结果,隔震层位移减小,支座滞回曲线面积减小,同时剪力墙和楼板实际均出现了不同程度的弹塑性损伤.弹塑性楼板模型的层间剪力和位移角均大于弹性楼板假定模型的,顶点位移时程则滞后于弹性楼板模型的顶点位移时程,幅值变化不大.

To understand the nonlinear performance of the base-isolated structure under basic and rare earthquake excitations,a base-isolated high-rise shear-wall structure is analyzed with ABAQUS in this paper,which considers the local nonlinearity of the bearings and the damaged plasticity of the super-structure respectively.The different assumptions on the effects of slabs are also considered.The results indicate that when the full nonlinearities of the whole structures were taken into account,the seismic reduction factors decrease,the drifts increase and the displacement responses lag behind the result of the local nonlinear model,and moreover,the shear walls and slabs come into plasticity actually.Shear forces and drifts of the floors that resulted from elastoplastic slab assumption are obviously greater than that from elastic-slab assumption.