砂性土层中围堰法施工水底隧道渗透机理与防治技术  

Seepage Mechanism and Prevention Technology of Underwater Tunnel Constructed by Cofferdam Method in Sandy Soil Layer

作　　者：柳军修[1] 席培胜[1] 张兴其 严中 浦玉炳 王枫 席彬彬 肖博文 LIU Jun-xiu;XI Pei-sheng;ZHANG Xing-qi;YAN Zhong;PU Yu-bing;WANG Feng;XI Bin-bin;XIAO Bo-wen(Anhui Province Key Laboratory of Building Structure and Underground Engineering,Anhui Jianzhu University,Hefei 230601,China;Hefei Municipal Design Research Institute Co.,Ltd.,Hefei 230041,China)

机构地区：[1]安徽建筑大学建筑结构与地下工程安徽省重点实验室,安徽合肥230601 [2]合肥市市政设计研究总院有限公司,安徽合肥230041

出　　处：《佳木斯大学学报（自然科学版）》2020年第4期5-10,共6页Journal of Jiamusi University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51608005);安徽大学科技项目(横20190011,SGAHJYJSXLJS1800417);企业委托科技项目(AJ-CXY-FW-16-03-3,横20190003)。

摘　　要：强透水砂性土层水底隧道围堰法施工中,二期围堰和止水帷幕无法穿越已建隧道管节插入水底深处,止水结构在隧道管节下缺失,较小的水头差即可出现渗透破坏,严重威胁施工安全和工程质量。基于水底隧道砂性土地层围堰基坑涌水原因分析,建立围堰渗流三维数值模型,研究不同围堰止水结构的抗渗透性能,提出了由围堰止水帷幕与管节止水帷幕组成的水底隧道强透水砂性土层抗渗透破坏结构,得出设置管节下止水帷幕或基坑止水帷幕可使渗流最大流速降低为无止水帷幕工况的0.3%~0.8%。研究成果对工程设计与施工有指导意义。In the construction of underwater tunnel by cofferdam method in strong permeable sandy soil layer,the second stage cofferdam and water curtain can’t penetrate the existing tunnel pipe and insert into the deep soil layer.The water curtain is missing under the tunnel pipe,and the seepage damage can occur with small hydraulic gradient,which seriously threatens the construction safety and engineering quality.This paper analysed the cause of water inflow of cofferdam foundation pit in sandy soil layer of a underwater tunnel,and a three-dimensional numerical model of cofferdam considering water seepage was established.The impermeability of different cofferdam structures was studied and the anti-seepage structure of the underwater tunnel was proposed.The anti-seepage structure is composed of the curtain of cofferdam and tunnel tube for cutting off water.The results show that when the curtain for cutting off wateris set below the tunneltube or set on both sides of foundation pit,the maximum flow velocity can be reduced to 0.3%~0.8%of the no curtain condition.The research results have guiding significance for engineering design and construction.

关 键 词：水底隧道 砂性土地层 抗渗透破坏 围堰法 

分 类 号：U411[交通运输工程—道路与铁道工程]