猴子岩水电站大坝深窄基坑开挖施工技术

猴子岩水电站面板堆石坝坝址河谷深、岸坡陡、覆盖层深厚、最大下挖深度85.5 m。为确保基坑开挖,采用上下游围堰防渗墙及墙下帷幕、大坝基坑抽排水优化、基坑厚层粘质粉土开挖施工技术,解决了工程难题。

Construction Techniques for Deep and Shallow Foundation Pit in Houziyan Dam

The construction of the concrete face rockfill dam in Houziyan hydropower station is of great difficulties due to the deep and shallow valley , steep slope, deep overburden and maximum excavation depth over 85.5 m.To ensure the safety of foundation pit excavation , some construction techniques are successfully adopted , including the cut-off walls and the curtain grouting underneath the upstream and downstream cofferdams , optimized water pumping and drainage schedule of the pit , special excavation technique for deep clayey silt in the pit .