土与结构相互作用体系振动台模型试验数值模拟研究(英文)

运用土与结构动力相互作用 (SSI)有限元三维分析软件 SASSI2 0 0 0对一个土与结构动力相互作用体系振动台模型试验进行了模拟计算。对振动台模型试验作了简单的介绍 ,并详细叙述了试验的建模方法。对于试验中的刚性地基和柔性地基条件 ,El- centro波、Taft波和 5 0年超越概率为 10 %的南京人工波等三种地震波输入 ,三个加速度峰值水平 0 .1g、0 .2 g、0 .3g及两个水平向地震波输入的各种组合工况均进行了计算。在数值计算中 ,假设地基土为覆盖于基岩上的半无限粘弹性水平成层土 ,采用等效线性模型考虑土的动力非线性的影响 ;上部结构用三维杆系有限元单元模拟 ,楼板用四结点壳单元模拟 ,每个结点有三个平动自由度和三个转动自由度 ,模型试验中所施加的人工质量均匀分布于壳单元上 ;基础视为平板基础 ,用八结点块体单元模拟 ,每个结点有三个平动自由度。将试验结果与计算结果进行对比较 ,结果表明 :计算所建立的模型较好地模拟了相互作用体系在地震荷载下的反应性状 ,计算结果与试验结果吻合较好 ,SSI效应对结构地震反应有很大影响

Numerical Modeling of the Shaking Table Test of Soil-Structure Interaction System

Numerical modeling of a soil-structure interaction (SSI) system model is performed by Program SASSI2000 in this paper. The shaking table test and the analytical methods are briefly reviewed in this paper. The seismic responses of superstructure overlying two types of ground are calculated by Program 2000,associated with real combinations of three seismic events,three input peak acceleration levels and two input directions. Comparisons between the test and calculatation results indicate that the analysis model is able to simulate the performance of SSI system under seismic excitation,and the calculated results are in fairly agreement with the test results.However,it shows that the seismic responses of superstructure on soft soil under strong ground motions are different from that of tests to some extents in that the finite field region in a flexible container in the tests is replaced by the semi-infinite horizontal layers in the analysis. Both the test and numerical results obviously show that SSI effects have an important influence on the seismic responses of superstructure.