黄金坪水电站大厚度超百米深防渗墙施工技术

Construction Technology of Large Thickness Cutoff Wall with Depth over 100 m in Huangjinping Hydropower Station

黄金坪水电站大坝防渗墙最大孔深为129.5m,墙体厚度1.2m,漂孤石架空层严重、大孤石含量高,工程地质条件复杂,是目前同等墙体厚度下国内最深的防渗墙。考虑到深墙在2013年主汛期高水位下施工的高风险性,防渗墙超百米深槽段要在主汛期到来前完成,因此工程工期非常紧张,并且施工难度很大。对黄金坪大坝防渗墙施工过程、总体布置、施工工艺、施工难点及解决措施等进行了归纳总结,以期为类似工程提供可借鉴的经验。

The maximum hole depth of cutoff wall is 129. 5 m and the thickness of wall is 1. 2 m at Huangjinping Hydropower Station, which is the deepest cutoff wall with same thickness in China. As the drift boulder overhead layer is serious and the big boulder content is high, its engineering geological conditions are very complicated. Taking into account the high construction risk under the condition of high water level in main flood season of 2013, the deep groove section of cutoff wall with a depth over one hundred meters must be completed before main flood season. So the construction period is very tight and the construction is very difficult. The construction process, overall layout, construction technology and construction difficulties of cutoff wall are summarized to provide a reference for the construction of similar engineering.