新疆下坂地水库坝基防渗墙试验施工

Trial construction of the cut-off wall for the foundation of Xiabandi Reservoir in Xinjiang

新疆下坂地水利枢纽工程地处高寒、高海拔的边远山区。坝基覆盖层厚达147.95m,透水性强,易坍塌和漏浆,块石坚硬,坝基防渗处理难度罕见。试验表明,以大深度混凝土防渗墙为主墙,下接帷幕灌浆的墙幕结合方案可行,并创造了防渗墙深度、墙内预埋灌浆管深度、1000mm接头管起拔深度三项全国第一,其中墙内预埋灌浆管深度、1000mm接头管起拔深度为世界之最。

The Xiabandi Water Control Project in Xinjiang is located in a remote mountainous area with high cold and high elevation. The over-burden layer of dam foundation is up to 147.95 m thick and is strong pervious, easy collapse and easy slurry-leakage and hard rock blocks, so that it is difficult to treat the seepage of dam foundation. The tests showed that it is feasible to adopt the combination of the deep concrete cut-off wall with curtain grouting. In this project, such method creates the Three-First in the country, that is, the depth of cut-off wail, the depth of pre-buried grouting pipe in the cut-off wall, and the start-pull depth of F1000 mm pipe. Moreover, the depth of pre-buried grouting pipe in the cut-off wall, and the start-pull depth of F1000 mm pipe ranks the first in the world.