土-结构动力相互作用1∶4大比例模型试验研究(英文)

SSI effects on the dynamic behavior of structures:Experimental study on a 1/4 scaled steel-frame building prototype

进行土-结构动力相互作用1∶4比例钢框架模型试验研究。分别在刚性地基与柔性地基上改变上部结构刚度与质量17种工况下进行模型顶部牵引释放试验,在时域与频域内取得并分析了试验数据结果。研究表明,土-结构相互作用系统效应随着试验控制参数变化而变化。其中上部结构与地基刚度比乃最为重要控制因素,随着上部结构与地基刚度比增大,土-结构动力相互作用影响更为明显,表征为柔性系统对刚性系统基本周期比与阻尼因子明显增大;上部结构与地基等效质量比变化对土-结构系统影响不甚明显。最后给出基本周期比与阻尼因子随结构与地基刚度比和质量比取值变化经验公式。

This study involves a 1∶4 scaled steel-frame structure model experiment in the SSI laboratory of Hunan University. The experimental data of the soil-structure interacting system were documented and then analyzed in time and frequency domains under 17 different scenarios with varying stiffness, mass of the superstructure and different fixed or flexible foundation conditions. The results show that the effect of soil-structure interaction is dependent on several controlling experimental parameters, and the stiffness ratio of the superstructure with respect to the soil immediately beneath the structure plays a dominant role in SSI effect. By increasing the structure-to-soil stiffness ratio, the SSI effect changes substantially as characterized in significant period elongation and increase in damping factor of the overall system. The structure-to-foundation mass ratio, on the other hand, affects the SSI effect moderately. Empirical formulas for the relationships of the fundamental period ratio and damping factor with structure-to-soil stiffness ratio and mass ratio are presented.