四川大渡河猴子岩水电站量水堰防渗墙施工技术

Construction Technology of Cut-off Wall for Measuring Weir of Houziyan Hydropower Station in Sichuan

四川大渡河猴子岩水电站大坝量水堰防渗墙覆盖层主要为漂(块)卵(碎)砾石层,地层中含有较多大孤石,墙体需嵌入基岩1.0 m,墙厚1.0 m,最大深度76.42 m,在防渗墙轴线往上游28 m处有两口集水井,2台250 k W的抽水机24 h不间断地抽水。针对墙原、槽深、地质条件复杂的特点,在槽孔混凝土防渗墙施工中,采用特殊处理技术措施,保障槽孔顺利施工,防渗墙总体质量控制情况良好。

The covering layer of cut-off wall of measuring weir of the project is a stratum mainly composed of boulder（block） pebble（broken） gravel, in which many large boulders are found. The wall is 1.0m into the bedrock; besides, the wall is 1.0m thick, with maximum depth of 76.42 m. There are two collecting wells 28 m upstream the axis of cut-off wall, two pumps with single capacity of 250 k W are provided for 24 h uninterrupted pumping. Based on the characteristics of thick wall, deep slot and complicated geological conditions, special technical measures are adopted during the construction of slot concrete cut-off wall, ensuring the smooth construction of slot and the control of overall quality of cut-off wall.