自由场与土-地下结构场动力特征对比分析

Comparison of the dynamic characteristics for the free field and soil-underground structure interaction field

通过数值模拟的手段,比较分析了自由场与土-地下结构相互作用场的动力特性,重点研究了土体及结构在相对位移最大时刻的动力反应与其最大动力反应之间的联系。结果表明:(1)自由场中土体的内力状态由相对位移或应变控制,且是一种局部现象;(2)土-地下结构相互作用场中,在结构相对位移达到最大时刻,结构及结构附近的土体的内力也达到最大值;(3)采用自由场的剪应力,然后再通过改变剪应力的分布形式,可以很好的模拟出土-地下结构相互作用场的内力状况。

By means of the numerical simulations, the dynamic characteristics for the free field and soil-under- ground structure interaction field are comparative studied, focusing on the contact of the max and the time when the maximum relative displacement dynamic response of the soil and the structures. The results show that ： （ 1 ） The in- ternal forces of free field is controlled by the relative displacement or strain, and it is a local phenomenon ; （2） The internal forces of the structure and the soil near the structure reaches the maximun value, when the structure rea- ches the maximun relative displacement ; （3） The use of shear stress from free field, and then by changing the form of the shear stress distributions can be well simulated the soil-underground structure internal force conditions.