采用止水挡墙的基坑渗流场模拟

Simulation of seepage field in the foundation pit adopting cut-off wall

在分析土体饱和渗流的有限元求解方法的基础上,对采用不同止水挡墙的基坑渗流场进行了模拟分析.计算结果表明,随着止水挡墙长度的增加及渗透系数的减小,基坑内部降排水对外侧地下水位变化的影响逐渐减小,基坑底部的渗流量、垂直流速和水力梯度等都随着距支护墙体距离的增加而减小,减小到一定程度后逐渐趋于稳定.计算结果还表明,计算模型尺寸对计算结果也有影响,但随着模型尺寸的增大,其影响越来越小.

On basis of analyzing the solution method of saturated seepage in soil by finite element method, the seepage field in the foundation pit with different cut-off walls is simulated. The calculation results show that the influence of the draining in the foundation pit on the change of the underground water table outside the pit gradually decreases with the increase of the height of the cut-off wall and the decrease of the permeability coefficient. And the seepage discharge, vertical velocity and hydraulic gradient at the bottom of the foundation pit all decrease along with the increase of the distance from the cut-off wall, but when decreasing to some extent, they all gradually tend to be stable. Meanwhile, the dimension of the calculation model will influence the calculation result, but with the increase of the dimension, its influence will become less and less.