Model Investigation of Flow Hydraulics over Block Ramps

IJEP 42(11): 1361-1366 : Vol. 42 Issue. 11 (November 2022)

Vishal Singh Rawat and Thendiyath Roshni*

National Institute of Technology, Department of Civil Engineering, Patna, Bihar- 800 005, India


Block ramps uniquely serve as an essential paradigm in riverine management, to encounter deliveries in an ecologically sound manner. It permits safe fish passage, stabilizes stream banks and bed profiles and creates habitat diversity. Model studies of flows over block ramps are quite extensive and are associated with many intricacies. In this paper, experiments were conducted at two flumes with three different model configurations in the hydraulic laboratory of National Institute of Technology, Patna. A comparison of the performance of three different model configurations of flows on the block ramps placed in channels with horizontal beds was studied. Experimental data analysis allowed describing the erosion mechanism occurring in the stilling basin, energy dissipation and friction factor in the interstitial flow over rock ramps. The results of physical testing can be used to assess and predict scour development downstream of block ramps, effective dissipation of energy and its impact on the stability of rock structures.


Hydraulic modelling, Block ramps, Sediment transport, energy dissipation, Scour depth, friction factor


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