Hydraulic investigation of finite crested stepped spillways
Abbas Parsaie, Amir Hamzeh Haghiabi
Abstract
Abstract In this paper, the hydraulic properties of the finite-crested stepped spillway (FCSS) including discharge coefficient (Cd) and the ratio of energy dissipation (EDR) were experimentally investigated. Results indicated that the Cd of the FCSS changes between 0.9 and 1.2, while the ratio of the upstream head to the length of the crest (hup/Lc) changes between 0.25 and 1.8. The hup/Lc is the main parameter affecting the Cd. The value hup/Lc equal to 0.6 is a good criterion for designing the crest of the FCSS. At this point, the Cd of FCSS is about 1.0. The performance of FCSS regarding the EDR changes between 95 and 40 percent. By increasing the discharge of flow and skimming flow formation, the performance of the FCSS related to energy dissipation is dramatically decreased.