猴子岩水电站大坝上下游围堰施工总结

Cofferdam construction of Houziyan Hydropower Station

猴子岩水电站大坝围堰工程地质条件复杂,工期紧,施工强度大,是水电站发电直线工期上的关键项目,防渗墙深约80 m,墙下帷幕深约55 m。建设期间,针对防渗墙施工过程中出现的诸如槽孔漏浆及坍塌、混凝土浇筑串槽、混凝土塌陷、造孔掉钻与埋钻等特殊情况,采取了相应处理措施,均未形成质量缺陷。为确保围堰工程的施工质量,业主引进第三方质量检测单位,把关隐蔽工程质量;聘请防渗墙、灌浆施工的专家顾问,长驻现场指导,全程参与围堰工程的施工,并对施工一线的民技工开设现场课堂,在施工细节上进行指导。工程于2011年11月开工,2012年5月完工,围堰在汛期的运行实践表明,施工质量达到了预期目的。

The cofferdam for the dam construction of Houziyan Hydropower Station, with 80m-depth cutoff wall and 55m-depth curtain below, is characterized as complex geological condition, high construction intensity and tight construction schedule, and is the key works for achieving the goal of power generation. In the construction, quality defects were prevented effectively af-ter several measures were adopted to successfully tackle the problems such as grouting leakage, drilling hole collapse, mixing of concrete in different troughs, subsidence of concrete, drill blocking and burying. Furthermore, comprehensive measures were taken to ensure the cofferdam construction quality, i. e. , employing the third party to participate in quality check, especially for the concealed works, inviting related experts to the construction sites of cutoff wall and grouting in the whole process, and training of construction workers. The construction started in November, 2011 and completed in May, 2012, and the operation practice of cofferdam in flood season showed that the construction quality was as good as expected.