The Proposal and Comparative Study of Curved Stepped Spillway

Abstract: As an important drainage structure in water conservancy and hydropower projects, the bank spillway is widely used in earth-rockfill dams or rockfill dams. Be affected by topographic and geological conditions, water flow convergence and other factors, the spillways on the bank of many actual projects need to set up a plane curve transition. In this paper, based on the actual project of setting up a flat curved bank spillway, aimed at the problem of using normal smooth spillway and local ultra-high spillway cannot meet the safety requirements of flood discharge, a plan of arranging stairs in curved corners was put forward, namely, the curved stepped spillway. The article used the research method combining model test with numerical simulation, and comparative analyzed hydro mechanical indexes such as waterline, flow velocity and energy dissipation ratio under various layout schemes and their changing rules. The research results showed that the curved stairway spillway can make the water flow pattern in the runner and the downstream stilling pool more smooth, the cross-sectional flow velocity and water depth distribution became more uniform, and can greatly reduce the flow velocity along the spillway and increase the friction energy dissipation rate. The research results can provide theoretical guidance and some reference value for the design of similar projects. However, the influence laws of turning radius, step height and slope on hydraulic parameters need to be further studied.