Author(s): Hans-Erwin Minor; Robert M. Boes
Linked Author(s): Robert Boes
Keywords: Stepped spillway; Energy dissipation; RCC dam; Air-watermixture; Air concentration
Abstract: The hydraulic design of stepped spillways follows the planning sequence of con-ven-tional chutes: Flood analysis, selection of design flood and safety check flood, selection of weir type and width, design of weir crest, definition of the stage-discharge curve, calculation of reservoir retention. Additionally, for stepped spillways the selection of step height and the analysis of flow regime and air entrainment are necessary. The design of the sidewalls has to take into account the bulging of the air-water mixture, and the energy dissipation profits from higher energy losses along the steps compared to smooth chutes. The latter is however smaller than often assumed. Higher steps have a positive effect on the hydraulic performance of the spillway.
Year: 2001