New layouts and designs of the underground structures of the Kambarata No. 1 hydroelectric station

Conclusions

• 1. The combination of the functions of a delivery tunnel of a hydrostation and service outlet in one structure makes it possible to dispense with the construction of two separate lines of discharge tunnels with a length of more than 1500 m.

• 2. The installation of trash racks at the branch point of the combined power-discharge tunnel instead of the traditional location at the head of the tunnel and the use of their hydraulic cleaning reduce construction costs by eliminating a tower intake, increase the reliability of the structure, and substantially facilitate its operating conditions.

• 3. The construction of an underground shaft stilling basin dissipating the excess kinetic energy of the flow reduces the risk of occurrence of cavitation erosion of the lining of the discharge tunnel and precludes the possibility of undercutting and caving of the slopes beyond the end structures of the discharge tunnels.

• 4. The construction of a diversion tunnel provides reliability of constructing structures of the hydrostation at individual stages of construction and reduces to safe limits the concentration of residual products of explosives in the lower pool of the hydrostation.