东江水利枢纽一期工程混凝土防渗墙施工

Concrete seepage prevention wall construction of Stage I works of Dongjiang Hydro Project

混凝土防渗墙是在松散透水地基中以泥浆固壁连续造孔成槽，在泥浆下浇筑混凝土材料筑成的、起防渗作用的地下连续墙。它是工程闸坝基础垂直防渗的主要手段，也是关系到闸坝安全和坝体稳定性的关键工序。东江水利枢纽一期工程集中在右河汊，主要由船闸、12孔拦河闸坝、发电厂房组成。依据设计，坝基防渗为地下混凝土防渗墙，防渗墙厚0．6m，为C20W6混凝土，底部深入基岩1．0m，平均深度约12～18m。从船闸连接段至右拦河闸坝与发电厂房相接形成一个封闭的防渗系统。对防渗墙的施工过程和施工工艺作了详细介绍。

Concrete seepage prevention wall in loose and pervious foundation is constructed through groove formed by continuously boring hole and side wall consolidated by slurry,and grouting concrete in slurry to play a role of seepage prevention.The concrete seepage prevention wall is a main means to prevent seepage for the foundation,of sluice and dam,it is also a key structure for sluice safety and dam stability.The stage I works of Dongjiang Hydro Project concentrated in right river channel,mainly including ship-lock,river weir with 12 flow passages,powerhouse.According to design,the underground seepage prevention wall is constructed to prevent seepage for dam foundation,the seepage prevention wall is 0.6 m thick,constructed by C20W6 concrete,its bottom enters foundation rock 1 m,the average depth is 12~18 m.A closed prevention system from continuous section to right river weir and power generation house is formed.This paper introduces the construction process and construction technology of the seepage prevention wall in detail.