矩形闭合地下连续墙基础沉降特性分析

在有限元分析的基础上,采用Drucker-Prager弹塑性模型对黄土层中地下连续墙的沉降特性进行了较详细的探讨。计算结果表明:墙端阻力的大小决定了土体的竖向沉降变形,墙端以下土体的竖向沉降变形主要产生在墙端下约1.5倍基础宽的深度范围内,且沉降量随着深度的增加而迅速减小;竖向荷载作用下墙芯土体竖向沉降变形值在墙顶附近最大,沿深度方向逐渐变小,在墙端附近其值变化速率最大,墙端以下土体沉降迅速衰减为零;墙外侧土体竖向变形沿深度先增加,由于端阻力的的作用,在墙端附近达到极值,然后减小并趋于零;在水平面上,竖向变形从墙侧向外逐渐减小并趋于零,在墙体接触面附近其值最大;墙周土体的变形模量对基础沉降的影响大,而土体的泊松比对基础沉降的影响较小,提高墙土接触面的摩擦系数有利于减小基础沉降。

Analysis of Settlement Property of Rectangular Closed Diaphragm Wall

On the basis of finite element analysis,a comprehensive study on the settlement property of diaphragm wall,as well as its influencing factorssuch as modulus of deformation,Possion's ratio and coefficient of friction are carried out.It brings forward the finite element method of settlement property of diaphragm wall in loess using Drucker-Prager elastoplastic model.The results of the analysis shows that the vertical settlement of loess is subjected mainly to the amount of diaphragm wall toe resistance,the vertical deformations of loess always take place in the depth as 1.5 times width as the foundation below the diaphragm wall toe,and the amount of vertical settlement of loess decreasing rapidly with the increase of depth;the vertical settlement value of loess inside of the diaphragm wall is maximum near the head of the wall under vertical loading,and decrease gradually with the depth to zero,and with a maximal movement ratio near the diaphragm wall toe;the vertical deformations of loess outside of the diaphragm wall along the depth firstly increase,then decrease,and reach the maximal settlement value at the bottom of the diaphragm wall because of the toe resistance;at the horizontal direction,the value of vertical settlement is maximum about the contact surface,then decrease slowly outward to zero;the modulus of deformation of loess influencing greatly on the settlement of foundation,but Possion's ratio of loess minor on the settlement;and the improving coefficient of friction of the contact surface is favourable to reduce the settlement of foundation.