New designs of spillways at earth dams

Conclusions

• 1. When designing reservoir structures it is recommended to design overflow spillways according to the principle of increasing the length of overflow with limited planar dimensions of the inlet by transferring the region of water conveyance within the inlet to a lower elevation from the free surface and using the water space freed in so doing for additional intake of water.

• 2. The placement in the trench o additional channels with spillway walls on transverse beams or props makes it possible to increase the length of overflow up to three times and to increase the capacity of the spillway by just as many times compared with known analogous design.

• 3. The dead weight of the inlet with the spillway walls and weight of the water above it reduce the uplift pressure in the foundation of the structure, which helps to lighten the proposed spillway layouts.

• 4. The inflow of water into the trench in transverse and longitudinal directions provides uniform joining of the additional water masses to the main flow over the entire area of the free water surface in the trench, which completely eliminates the occurrence of transverse circulation and creates normal hydraulic conditions of flow both in the inlet and in the water passage of the spillway.