Block Ramp Design for Efficient Energy Dissipation

Abstract

Block ramp structure can be a part of a layout of microhydel scheme, depending upon the conditions of topography and geology at the site. Block ramps transmit the flow of stream to a lower level inducing kinetic energy dissipation. Block ramps consists of base material in the form of stones inducing roughness whereas stepped chutes are overflowing structures which consists of step configuration at the bottom of the flowing stream. As there is a common objective of energy dissipation of flow, the geometrical elements of block ramps and stepped chutes are considered to be comparable under similar hydraulic conditions of skimming flow. This paper analyzes the experimental results on both these structures. A mathematical model in dimensionless form is proposed herein, which correlates the representative bed material size of block ramp with the step height of stepped chute. This correlation is expected to facilitate the design of block ramps using the literature available on stepped chutes.