基于土石围堰的子围堰应用效果评价

针对航电枢纽工程中土石围堰防渗效果问题，以岷江龙溪口航电枢纽工程为工程背景，在围堰内侧增加子围堰差解决围堰渗水的问题。通过对比高喷旋喷桩补强、水泵排水等方式，研究子围堰在质量、工期、成本等方面的优势。实际应用表明，子围堰可对原有围堰的防渗效果起到较好的增强作用，相较于在原有围堰的基础上使用高喷旋喷桩或者水泵强排的方案，子围堰在施工难度和经济效益方面更有优势。研究成果可为长江上游类似工程提供参考。

Application effect evaluation of sub cofferdam based on earth-rock cofferdam

To solve the problem of anti-seepage effect of earth-rock cofferdam in the navigation-power junction project,this article takes Longxikou Navigation-power Junction project in Minjiang River as engineering background,and adds a sub cofferdam difference on the inner side of the cofferdam to solve the problem of cofferdam seepage.The article studies the advantages of sub cofferdam in quality,construction period,and cost by comparing the reinforcement of high-pressure jet grouting piles and water pump drainage.The practical application shows that the sub cofferdam can effectively enhance the anti-seepage of the original cofferdam.Compared with the scheme of using high-pressure jet grouting piles or water pump forced drainage on the basis of the original cofferdam,the sub cofferdam is a good choice in terms of construction difficulty and economic benefits.The research results can provide reference for similar projects in the upper reaches of the Yangtze River.