滑移隔震结构考虑土-结构动力相互作用的动力分析

Analysis of Sliding Isolation Structures Considering Dynamic Soil-structure Interaction

介绍了考虑土 结构动力相互作用的滑移隔震结构的动力分析方法。应用正交多项式系逼近连续型基底摩擦力函数 ,实现了基底摩擦力的傅立叶变换 ;然后利用地基土动力刚度矩阵 ,在频域内采用子结构法 ,建立了考虑土 结构动力相互作用的滑移隔震结构的运动方程 ;通过数值仿真两个具有埋置刚性基础的剪切型滑移隔震结构的地震反应 ,分析了土 结构动力相互作用对滑移隔震结构地震反应的影响 ,以及上部结构刚度的不同引起相互作用影响程度的差异 ,从而得出结论 :考虑土 结构动力相互作用 ,会降低滑移隔震结构的隔震效果 ,其降低程度与上部结构的刚度成正比 ;能显著地减小隔震层的侧移 ,有利于地震时穿越隔震层的电路和管线等设备的保护。

In this paper, the dynamic analysis for sliding isolated structures considering the soil structure dynamic interaction is performed. The Flourier transformation for base friction forces is realized by employing the orthogonal polynomials to approach the continuous function of the base friction forces. The equations of motion of the sliding isolated structures considering the dynamic soil structure interaction are established by means of the substructure method in the frequency domain and the dynamic impedance matrix of soil. The seismic responses of two shear type sliding isolated structures with embedded rigid foundations are numerically simulated, and the influence of the dynamic soil structure interaction on the seismic responses of the sliding isolated structures and its difference due to the different stiffness of the superstructures are investigated. It is concluded that considering the dynamic soil structure interaction may reduce the isolation effect of the sliding isolated structures and the reduction is in direct proportion to the stiffness of the superstructure. The shift in the isolated stories may be also decreased significantly, which is favorable for protecting the equipment crossing the isolated stories such as circuits and pipelines during earthquakes.