台州地区地铁基坑围护墙体水平变形特性及基底最优加固深度研究

Lateral Deformation Characteristics of Underground Diaphragm Wall and Optimal Strengthening Depth of Subway Station Foundation Pit in Taizhou Area

本文结合台州市某地铁工程实例,采用FLAC3D有限差分软件和现场监测相结合的方法,对地铁车站基坑围护墙体的水平变形特性进行了分析。在各种工况下围护墙体水平位移均呈“弓”型分布,随开挖深度增加墙体最大水平位移逐渐增加,最大水平位移深度也随之增加。土体具有蠕变特性,围护墙体的水平变形具有明显的时间效应。基坑底部土体的最优加固深度为6m,当加固深度小于6m时,加固深度增加,可以减小围护墙体的水平位移,当加固深度大于6m时,加固深度增加对围护墙体水平位移影响不明显。

Based on an example of a subway project in Taizhou City,this article analyzes the horizontal deformation characteristics of the retaining wall of the subway station foundation pit using a combination of FLAC3D finite difference software and on-site monitoring.Under various working conditions,the horizontal displacement of the retaining wall shows a bow shaped distribution.As the excavation depth increases,the maximum horizontal displacement of the wall gradually increases,and the maximum horizontal displacement depth also increases.The soil has creep characteristics,and the horizontal deformation of the retaining wall has a significant time effect.The optimal reinforcement depth for the soil at the bottom of the foundation pit is 6 meters.When the reinforcement depth is less than 6 meters,the reinforcement depth increases,which can reduce the horizontal displacement of the retaining wall.When the reinforcement depth is greater than 6 meters,the effect of increasing the reinforcement depth on the horizontal displacement of the retaining wall is not significant.