An investigation of flow and energy dissipation for stepped spillways with end sill

ABSTRACT MSc Thesis AN INVESTIGATION OF FLOW AND ENERGY DISSIPATION FOR STEPPED SPILLWAYS WITH END SILL Muhammed Cihat TUNA Firat University Graduate School of Natural and Applied Sciences Department of Civil Engineering 2004, Page: 79 Stepped spillways have regained popularity over the last 2 decades with the evolution of the roller compacted concrete (RCC) dam construction technique. A stepped chute can be economically integrated into the downstream face of a RCC gravity dam. Another common application is the use of stepped overlays on the downstream face of embankment dam as emergency spillways to safely pass the probable maximum flood (PMF) over the dam crest. Advantage of stepped spillways include ease of construction, reduction of cavitation risk potential, and reduction of the stilling basin dimensions at the downstream dam toe due to significant energy dissipation along the chute. The aim of this study is to determine the amount of the energy dissipation for stepped spillways with end sill, and hydraulics of the flow in stepped spillways for sill types used in this study. This study includes six section; these; In the first section, introduction is presented. In this section, especially, the aim of this study is given. In the second section, summary of literature is presented. In the third section, hydraulics of stepped spillways is given in detail. In the fourth section, experimental setup is introduced. In the fifth section, experiments, their results and discussions are presented. According to obtained experimental results, graphs are plotted and interpreted. In the sixth section, conclusions and suggestions are given. Keywords: Stepped spillways, Skimming flow, Nappe flow. Transition flow, Energy dissipation, RCC, Sill n