任意形式荷载作用下饱和土中桩的扭转振动特性研究

Dynamic torsional response of a pile embedded in porous-saturated soil under arbitrary transient loading

基于Biot提出的饱水多孔介质的波动方程,研究了均质各向同性饱和土中弹性支承桩的耦合扭转振动问题。通过采用拉普拉斯变换及分离变量法求得土体扭转振动位移形式解。利用桩土系统衔接条件和边界条件,进而得到了桩顶转角响应的拉普拉斯变换域解。进一步采用拉普拉斯逆变换技术,得到了任意形式激振荷载作用下桩顶转角时域响应的数值解。最后,研究了骤加荷载和三角形荷载作用下主要参数对桩顶转角时域响应的影响。

Based on Biot's dynamic wave equation for porous-saturated soil,the response of an elastic supporting pile embedded in homogeneously isotropic saturated soil and subjected to a transient torsional loading was theoretically investigated.At first,the vibration displacement of the saturated soil was solved by using Laplace transformation and the separation of variables technique.By utilizing the continuity and boundary conditions of the pile-soil system,the dynamic response of the twist angle of the pile top was obtained in a closed form in Laplace transformation domain.Then,by virtue of the inverse Laplace transformation technique,the numerical solution to the response of the twist angle of the pile top under arbitrary transient torsional loading was obtained in time domain.Finally,the influence of the major parameters on the dynamic response of the twist angle of the pile top subjected to the step and triangular loadings was investigated.