土-结构动力相互作用体系基频试验研究

Experimental study on fundamental frequency of soil-structure dynamic interaction system

为了研究土-结构动力相互作用体系的基频,进行了室内刚性地基上和土槽中1/4钢框架模型的顶部牵引释放试验,得到模型刚度不同时,刚性地基上和土槽中结构体系的基频。根据试验结果得到钢框架模型基频折减率和上部结构与地基相对刚度比的关系式。研究结果表明:土-结构动力相互作用(SSDI)使结构体系基频降低,基频折减率最大为29.37%;基频折减率和上部结构与地基相对刚度比有关,相对刚度比越大,折减率越大。

In order to investigate the frequency of the soil - structure system, a 1/4 steel frame model experiment was carried out on rigid groundsill and soil - trough in door respectively. Fundamental frequencies of the model with different stiffness on rigid groundsiU and soil - trough were obtained respectively. The relationship between the fundamental frequency discount and the relative stiffness ratio was obtained by data fitting. The results show that the fundamental frequency of the soil - structure system decreases obviously because of the effect of the soil - structure dynamic interaction （SSDI）, and the maximum discount of the fundamental frequencies is 29.37%. The discount of fundamental frequency has a close relationship with the relative stiffness ratio between superstructure and groundsill and it increases with the relative stiffness ratio.