The Main Water Problems and Corresponding Countermeasures of Deep Underground Water Conservancy Project in Water-Rich Area

With the development of hydropower resources in water-rich karst areas in southwest of China, the success or failure of the construction of underground works will matters lots about the results of the entire process, and the key problems of the construction of underground projects is the water problems. In this paper, a depth analysis of the main problems on water of deep underground projects in Water-rich area has been done in conjunction with the situation of the Jinping grade II Hydropower Station under construction in China. Besides, the influence of water problems on the constructions of the projects has been simply analyzed and evaluated. The water management principle that "water blockage combined with water drainage, comprehensive treatment by Local conditions" has been proposed. Some treatments such as consolidation grouting of high confining pressure rock, underground water blockage etc. have been adopted to ensure the stability and security of the surrounding rock and the lining support structure, and effective control of water inflow combined with the use of grouting surrounding rock and tunnel lining joint bearing support functions. Theoretical basis and good engineering practice are provided for the construction of such project.