Toe Scour of Seawall on a Steep Seabed by Breaking Waves
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 135, Issue 2
Abstract
This paper reports experimental results of the toe scour of seawall on a steep seabed with slope of 1:5 under the action of breaking waves. The equilibrium toe scour profiles were investigated and the depths of toe scours related to the wave parameters were analyzed. Experimental results indicated that the depth of toe scour increased as the steepness of the incoming wave increased, but decreased with an increase in the water depth at the toe. The breaker types in front of the seawall were investigated. The scour depth due to a plunging breaker is larger than that of a spilling breaker or a nonbreaking wave in front of the seawall. The down-rush flow velocity induced from the wave rundown on the seawall was also investigated in the experiment, and it was found that the scour depth increased as the flow velocity at the toe increased. Empirical formulas of the relative scour depth in terms of the relative toe water depth or surf similarity parameter were obtained based on the experimental results.
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Acknowledgments
The writers are grateful to the National Science Council of Taiwan,NSCT for supporting this study under grant No. NSC 92-2611-E-005-001. The writers also appreciate the reviewers for their very valuable comments.
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Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 135 • Issue 2 • March 2009
Pages: 61 - 68
Copyright
© 2009 ASCE.
History
Received: Nov 20, 2007
Accepted: Sep 11, 2008
Published online: Mar 1, 2009
Published in print: Mar 2009
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