Reduction of Bend Scour by an Outer Bank Footing: Flow Field and Turbulence
Publication: Journal of Hydraulic Engineering
Volume 135, Issue 5
Abstract
River bank protection is a costly but essential component in river management. Outer banks in river bends are most vulnerable to scour and erosion. Previous laboratory experiments illustrated that a well-designed horizontal foundation of a vertical outer bank protruding into the cross section, called a footing, can reduce the scour depth and thereby protect the bank. This paper provides detailed experimental data in a reference experiment without footing and an experiment with footing carried out under similar hydraulic conditions, which suggest a delicate interaction between bed topography, downstream and cross-stream velocity, and to lesser extent turbulence. The presence of the outer bank footing modifies this delicate interaction and results in a more favorable configuration with respect to bank stability including: reduced maximum scour depth, more uniformly distributed downstream velocity, and weaker cross-stream circulation cells.
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Acknowledgments
This research has been sponsored by the Spanish Government Program Grant Nos. UNSPECIFIEDFPI-PN97 and UNSPECIFIEDFEDER 1FD97-2110-C02-01. The laboratory tests were performed in the Hydraulic Laboratory of the Civil Engineering School of Castilla-La Mancha.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 135 • Issue 5 • May 2009
Pages: 361 - 368
Copyright
© 2009 ASCE.
History
Received: Oct 11, 2007
Accepted: Nov 5, 2008
Published online: Feb 3, 2009
Published in print: May 2009
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