土与结构相互作用大比例模型试验研究

通过对土槽中的1/4比例的钢框架模型进行激振，测得柔性地基的结构在不同上部结构-地基相对刚度比条件下的加速度反应。把结构吊至刚性地面，输入相同的地震波，测得结构在相应工况条件下的加速度响应。根据上部结构动力平衡方程，求出结构底部的剪力。对比同一工况下柔性地基条件下和刚性地基条件下结构底部的剪力，可得结构的底部剪力折减系数。结果显示，上部结构-地基相对刚度比是影响土与结构相互作用的重要因素，随着上部结构刚度的变化，结构的底部剪力也发生明显的变化。

EXPERIMENTAL STUDY ON SOIL-STRUCTURE INTERACTION THROUGH LARGE SCALE MODEL TESTS

A four-story steel frame model on the soil-trough was prepared with the scale of 1/4,and excited to acquire the acceleration responses in different working conditions. And then the structure was fixed to the rigid ground and re-excited with the same seismic wave under the same working conditions,and the acceleration responses of the structure were acquired again. According to the dynamic equilibrium equation,the bottom shear force of the structure was calculated and compared between the flexible foundation structure and the rigid foundation structure. The results show that the relative stiffness ratio between superstructure and ground soil is a key factor for soil-structure interaction. As the relative stiffness grows,the bottom shear force changes significantly.