钻劈法施工在大岗山水电站围堰防渗墙工程中的应用

Application of Boring Cleaving Method in Cofferdam Anti-seepage Wall of the Dagangshan Hydroelectric Power Station

大岗山水电站上、下游土石围堰采用复合土工膜心墙普通混凝土防渗墙,防渗墙质量的好坏直接影响基坑开挖及大坝主体工程施工,意义重大。由于围堰地处狭窄的"V"形河谷地段,地势陡峻,且河床部位有多条辉绿岩脉、断层、破碎带穿插,地质条件十分复杂,给防渗墙施工带来了极大困难。本工程采用钻劈法施工工艺成功解决了防渗墙成槽难题。

The upstream and downstream concrete cofferdam of the Dagangshan hydroelectric power station uses usual concrete anti-seepage wall with composite geomembrane core-wall. It is of great significance because the quality of the anti-seepage wall will directly affect the construction of foundation excavation and the main work of the dam. The geological conditions are complex that the cofferdam locates in Vshaped valley area with steep terrain,moreover multiple diabase dikes,faults and fracture zone lie in riverbed,which brings greatly difficulties to the anti-seepage wall. The project solves how to make slot with construction technology of boring cleaving method.