Stability of Unstructured Block Ramps
Publication: Journal of Hydraulic Engineering
Volume 143, Issue 4
Abstract
Unstructured block ramps are fish-friendly structures to stabilize a riverbed, characterized by large macroroughness elements randomly placed on the riverbed. Physical model tests were conducted to investigate their stability and their behavior in case of overload. Different parameters describing the block and the base material were tested to find an optimal combination in terms of ramp stability with a maximum ramp slope typically in the range of 1–3%. A model for the determination of the ramp stability is presented, where the equilibrium slope of the ramp is related to a dimensionless specific discharge including information on the block size, the block placement density, and a characteristic grain size of the base material.
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Acknowledgments
The project was partly funded by the Swiss Federal Office for the Environment (FOEN). Dr. Gian Reto Bezzola is gratefully acknowledged for his valuable input.
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Published In
Journal of Hydraulic Engineering
Volume 143 • Issue 4 • April 2017
Copyright
©2016 American Society of Civil Engineers.
History
Received: Feb 1, 2016
Accepted: Aug 9, 2016
Published online: Oct 27, 2016
Discussion open until: Mar 27, 2017
Published in print: Apr 1, 2017
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