地连墙变形影响因素分析及支撑设计研究

Influence factor of underground continuous wall degeneration and its support design research

结合工程实例,利用有限元分析软件PLAXIS模拟地下连续墙设计参数,探讨不同设计对地连墙变形影响大小及差异,并根据分析结果对支撑设计方法进行优化。结果表明:适当增加墙体刚度,可以有效减小地连墙侧移;如满足地连墙最小入土深度,再增加入土深度意义不大;用混凝土支撑替换钢支撑、增加支撑刚度、减小支撑水平间距以及必要时在竖直方向上增加一道支撑对减小墙体变形具有较好的作用;同时对基坑周围软弱土体及结构薄弱区域进行土体加固对控制基坑变形效果明显。

Based on the engineering example of Nanjing city gate of Wuding subway foundation pit, the paper uses the finite element analysis software PLAXIS to simulate the design parameters of under- ground continuous wall. The influences of the different factors on underground continuous wall were discussed. The support design method was optimized by according to the comparison results. The re- suits show that increasing the stiffness of diaphragm wall can effectively reduce the lateral displace- ment of underground continuous wall ; if the depth of underground continuous wall meet with the mini- mum depth, then increasing the depth is of little significance ; the concrete support replace steel sup- port, which could increase the support stiffness, reduce the horizontal spacing and adding a layer of support along the vertical direction when it is necessary, which has good effect on reducing the de- formation of diaphragm wall ; At the same time, the soil reinforcement to the weak soil around pit sur- rounding and structure risk areas has a very good effect to control the deformation of foundation.