饱和地基中单排桩远场被动隔振研究

Three-dimensional analysis of a row of piles as passive barriers in saturated soil

针对均质饱和地基中单排桩远场被动隔振问题,基于饱和多孔介质的边界元法,建立了以薄层法(TLM)基本解作为动力Green函数的饱和土半解析边界元法,该方法可有效分析饱和半空间的动力问题,是解决土-结构动力相互作用问题的一种有效工具。在此基础上,根据排桩与周围土体的邻接条件,推导得到了单排桩对Rayleigh波散射的三维边界元方程;运用上述边界元方程,对单排桩的远场被动隔振问题进行了详细的参数分析。结果表明:单排桩能以一个整体对Rayleigh波进行隔振;增加单排桩的桩长、桩径和桩身剪切模量均能有效提高其隔振效果;减小桩间净距也能够有效提高屏障的隔振效果。

This paper presents a study on the problem of the ground vibration isolation efficiency by a row of piles as passive barriers in homogeneous saturated ground.The investigation is accomplished with the aid of the semi-analytical boundary element method（BEM） in cooperation with the basic solution of the thin layered method（TLM）.Consequently,a three-dimensional（3D） semi-analytical BEM model is put forward,where the TLM basic solution is employed,to use a row of piles as passive vibration isolation taking into account the dynamical interaction of soil—structure.Effect of the model parameters on effectiveness of vibration isolation by a row of piles is investigated and discussed in detail.The results show that a row of piles can function as an integrated system to isolate the ground vibrations due to the incident Rayleigh wave.Increasing the length,diameter and shear modulus of piles can result in an increase in the screening effectiveness.Moreover,decreasing the net spacing between two successive piles can also increase the screening efficiency.