横观各向同性圆形基坑抽水-水位恢复试验数值分析

为模拟井点抽水引起的圆形基坑内外水头变化以及地面变形,考虑水力特性和力学特性的横观各向同性及地下结构物的影响,建立了轴对称柱坐标系下的饱和-非饱和土固结模型.基于该模型,模拟两组圆形基坑抽水-水位恢复试验,分别研究弹性模量和初始饱和渗透系数的横观各向同性对水头和土体位移的影响.结果表明,当弹性模量越大时,水头越易改变,土体位移越小;当初始饱和渗透系数越大时,水头变化量和土体位移越小.

Numerical Analysis of Pumping-recovery Tests Performed on a Transverse Isotropic Circular Excavation

A consolidation model for saturated-unsaturated soil was formulated in axisymmetric cylindrical coordinates to simulate the hydraulic head changes and land deformations of circular excavations caused by well pumping．The transverse isotropic properties with respect to both hydraulic and mechanical properties were considered， so were the effects of underground structures．Based on this model，two groups of pumping recovery tests performed on a circular excavation were simulated to study the effects of transverse isotropy related to Young’s modulus and initial saturated hydraulic conductivity on hydraulic heads and soil displacements．The result shows that as Young’s modulus increases， hydraulic head changes get easier and soil displacements get smaller．As initial saturated hydraulic conductivity increases，both hydraulic head changes and soil displacements get smaller.