滩坑水电站面板堆石坝筑坝新工艺

New Dam Construction Technology of Facing Rockfill Dam of Tankeng Hydropower Station

滩坑水电站筑坝施工防渗墙施工不留龙口,实施先闭气后截流的导截流施工方案,使工期提前1个多月。采用抛石挤淤工艺,实现了基坑深覆盖层坝基开挖快速施工。汛期适当提高坝体填筑高程,在坝面高差处设置超径石保护,坝面经多次过流冲刷少,同时大大减少了溢洪道备料开挖。坝内预埋水管,高压水泵直供坝面喷射洒水,洒水均匀且经济安全。利用液压挖掘机作导向地锚,推土机牵引进行斜坡碾压,不需专用设备,坡面碾压质量好,实现了高面板坝优质快速施工。

The cutoff wall for Tankeng Hydropower Station was constructed without river-closure mouth. The construction measures of ＂air closure first and then river closure＂ are adopted which makes the construction period to be shortened over a month. The technique of throwing stones to crush silt was adopted to realize the quick excavation of deep foundation pit. The crest elevation of dam body was enhanced properly during flood season period and the protection measures using extra-diameter stones were taken in the dam surface. The surface of dam was less eroded after flowing over it many times and the excavation of reserve material of spillway was greatly reduced. There are premeditated water tube inside dam so that high pressure water pump can directly supply water to spraying on the surface of dam, which makes spraying water distribute well and reaches economy and safety. Hydraulic pressure excavator is served as direction anchor and bulldozer is to roll over the slope, so that special equipment is not needed but the roller compaction quality of slope is good, which realizes the quick high-quality construction of high facing roekfill dam.