Simple Design Criterion for Residual Energy on Embankment Dam Stepped Spillways
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VIEW THE REPLYPublication: Journal of Hydraulic Engineering
Volume 142, Issue 4
Abstract
The stepped spillway design is associated with significant flow resistance and associated energy dissipation on the steps, yielding smaller, more economical downstream dissipation structures. A number of design guidelines were developed for steep stepped spillways typical of concrete gravity dams. The focus of this study is on embankment stepped spillways. A large set of air-water flow data is compared with reanalyzed data sets to provide a simple unifying design approach for the residual energy at the stepped chute’s downstream end and to highlight the uncertainties involved. The results provided some simple design criteria in terms of the dimensionless residual energy of stepped chutes with flat steps. It is believed that a stepped design with a slope () might be optimum in terms of energy dissipation performances. The Darcy-Weisbach friction factors were close for all stepped data ranging between .
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Acknowledgments
The authors thank Dr. Jorge Matos (IST Lisbon) for his valuable comments. They acknowledge the technical assistance of Ahmed Ibrahim, Jason Van Der Gevel, and Stewart Matthews (The University of Queensland). The financial support of the Australian Research Council (Grants DP0878922 and DP120100481) is acknowledged.
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Information & Authors
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Published In
Journal of Hydraulic Engineering
Volume 142 • Issue 4 • April 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Nov 25, 2014
Accepted: Sep 15, 2015
Published online: Nov 19, 2015
Published in print: Apr 1, 2016
Discussion open until: Apr 19, 2016
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