Local Scour and Riprap Stability at Bridge Piers in a Degrading Channel
Publication: Journal of Hydraulic Engineering
Volume 130, Issue 3
Abstract
The experimental study examines local scouring and riprap stability at bridge piers in rivers subject to bed degradation. The data show that the equilibrium bed profile associated with that with or without a pier is essentially the same, except for the obvious section around the pier. Total scour depth is shown to be the sum of bed degradation and pier scour depth. The latter can be computed from the time-average live-bed scour depth associated with the undisturbed velocity ratio before bed degradation. The experimental data also show that pier-scour depth is invariant with time, for In a degrading channel, riprap around a pier will eventually develop into a stable mound when the bed shear stresses reduce with bed degradation. An auxiliary test shows that the mound is very vulnerable to another designed flood flow accompanied by large dunes. This type of riprap instability may be called bed-degradation induced failure.
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References
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 130 • Issue 3 • March 2004
Pages: 218 - 226
Copyright
Copyright © 2004 American Society of Civil Engineers.
History
Received: Sep 4, 2002
Accepted: Aug 28, 2003
Published online: Feb 19, 2004
Published in print: Mar 2004
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