Main technologies for construction of diversion tunnels of Jinping Hydropower Station II

The four diversion tunnels of Jinping Hydropower Station II are under a complicated hydro-geological condition with the characteristics of long tunnel axis of about 16.67 km,deep buried depth of about 1 500~2 000 m and large excavation diameter of about 13.0~13.8 m.In accordance with the specific construction condition therein,the technical measures such as geological prediction,control and prevention of rock burst,sudden water inrush,etc.are made,and then all the problems of deep buried depth,high geo-stress,sudden water inrush with large flow rate,strong rockburst,etc.are better solved with both the introduce world-advanced equipments and the self-developed horizontal curved face slip-form;which can provide a reference for the similar project.