Influence of Sediment Gradation on Scour Downstream of Block Ramps
Publication: Journal of Hydraulic Engineering
Volume 133, Issue 11
Abstract
The scour process downstream of block ramps is an important research topic of value to engineering practice. The object of the present experimental study is to examine the scour mechanism in order to predict the main geometrical parameters of the scour hole downstream of block ramps. The investigations have been conducted using two physical models located in the hydraulic laboratory of the Department of Civil Engineering in Pisa, Italy. Sediments with different values of the nonuniformity parameter were used as channel bed material. Moreover, different ramp slopes, ranging from 1/4 to 1/12, were tested. Equations and graphs demonstrate that the results can be interpreted by means of simple relationships in the case in which a ridge is present downstream of the scour hole.
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Acknowledgments
The writer wishes to thank Dr. M. Palermo and Dr. S. Mazzoncini for their help during the preparation of this work and the Reviewers for their pertinent and helpful comments.
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Information
Published In
Journal of Hydraulic Engineering
Volume 133 • Issue 11 • November 2007
Pages: 1241 - 1248
Copyright
© 2007 ASCE.
History
Received: May 16, 2006
Accepted: Apr 12, 2007
Published online: Nov 1, 2007
Published in print: Nov 2007
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