轴对称饱和地基竖向振动分析

基于Biot动力固结方程,考虑了土体和水体的惯性力以及水土之间的耦合作用,采用Laplace-Hankel积分变换求解耦联合方程组,得到动荷载下饱和地基振动问题的解答．根据下边界为不透水基岩的边界条件,获得了地基表面作用圆形轴对称任意荷载时土层应力、位移等的一般积分形式解．研究表明,激振频率对饱和地基的竖向振动有很大影响,地基表面的竖向位移与施加荷载之间存在相位差．此外,动力渗透系数在荷载施加的初期对结果有较大影响,随着荷载趋于稳定,其影响变得很小．     

VERTICAL VIBRATION ANALYSIS OF AXISYMMETRIC SATURATED SOIL

Based on Biot’s dynamic consolidation equations,by means of Laplace-Hankel transform technology,the integral solutions of stress and displacement in saturated soil with subjacent rock-stratum under axisymmetric arbitrary excitations were derived.In- fluence of the reflected wave generated by the boundary was revealed.Numerical results indicate that the vibration frequency has some effect on the vertical displacement of satu- rated soil.The vertical displacement at the surface of saturated soil lags in phase with the load.Furthermore,the dynamic permeability coefficient of saturated soil has significant effect on the vertical displacement at the initial stage of load applied,but when the load becomes stable,the effect is inapparent.