止水帷幕深度变化下长大基坑降水渗流场分析  

Analysis of dewatering seepage field of long foundation pit under the change of water stop curtain depth

作　　者：林联泉 叶代成 LIN Lianquan

机构地区：[1]厦门市建设工程质量安全站,福建厦门361003 [2]马銮湾新城开发建设总指挥部,福建厦门361028 [3]厦门百城建设投资有限公司,福建厦门361009

出　　处：《福建建设科技》2022年第1期44-48,共5页Fujian Construction Science & Technology

基　　金：厦门市建设局科技项目(XJK-2021-9);厦门百城建设投资有限公司科研项目“邻近地铁盾构隧道的明挖暗埋湖底隧道修建关键技术”。

摘　　要：为了解长大基坑止水帷幕深度变化对渗流场的影响规律,合理设计基坑止水方案,以厦门市某明挖暗埋湖底隧道工程为研究背景,考虑地层实际分布情况,利用PLAXIS 3D岩土有限元分析软件构建精细化三维数值模型,通过变化止水帷幕深度,计算止水帷幕与砂层的相对位置关系对基坑降水渗流的影响。计算结果表明:对于总渗流量,刚进入湖底段>陆地段>湖底段;由于长大深基坑地层空间分布复杂,止水帷幕深度局部未穿透砂层,陆地段和湖底段出现局部渗流量偏大现象;止水帷幕的局部加深,对地下水渗流有一定的控制作用。In order to understand the influence of the change of the depth of the water stop curtain on the seepage field of the long and large foundation pit,and to design the water stop scheme of the foundation pit reasonably,based on the research background of a tunnel project in Xiamen City,considering the actual distribution of the stratum,PLAXIS is used By changing the depth of the water stop curtain,the influence of the relative position between the water stop curtain and the sand layer on the dewatering and seepage of the foundation pit is calculated. The results show that: for the total seepage flow,just entering the bottom of the lake > the land > the bottom of the lake;due to the complex spatial distribution of the long and deep foundation pit,the depth of the water stop curtain partially does not penetrate the sand layer,and the local seepage flow in the land and the bottom of the lake is relatively large;the local deepening of the water stop curtain has a certain control effect on the groundwater seepage.

关 键 词：长大基坑 止水帷幕局部加深 有限元分析 渗流量 孔压场 

分 类 号：U459.5[建筑科学—桥梁与隧道工程]