Incipient Motion during Static Armoring
Publication: Journal of Hydraulic Engineering
Volume 118, Issue 3
Abstract
Critical bed shear stresses for grains in a mixed-size bed are known to depend on the ratio between the size of dislocated grains and an average grain size for the bed. However, laboratory experiments with sediments consisting solely of two fractions show that changes in armor-area concentration have a marked additional impact on critical stresses for the fines. If the bed area is covered up to 30% by static armor grains, critical stress for the mobile fraction is about the same as for unisize sediments, while as the specific armor-area approaches unity, critical stress increases by a factor of five. To a minor extent, critical stress also depends on a grain Reynolds number and the grain size ratio between the two fractions.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Ettema, R. (1980). “Scour at bridge piers.” Report No. 216, Dept. Civ. Engrg., Univ. of Auckland, New Zealand.
2.
Jain, S. C., and Park, I. (1989). “Guide for estimating riverbed degradation.” J. Hydr. Engrg., ASCE, 115(3), 356–366.
3.
Karim, M. F., Holly, F. M., Kennedy, J. F. (1982). “IALLUVIAL: A computer based flow and sediment routing model for alluvial streams: and its application to the Missouri River.” Report No. 250, Iowa Inst. of Hydr. Res., The Univ. of Iowa, Iowa City, Iowa.
4.
Karim, M. F., and Holly, F. M. (1986). “Armoring and sorting simulation in alluvial rivers.” J. Hydr. Engrg., 112(8), 705–715.
5.
Parker, G. (1990). “Surface‐based bedload transport relation for gravel rivers.” J. Hydr. Res., 28(4), 417–436.
6.
Parker, G., and Klingeman, P. C. (1982). “On why gravel bed streams are paved.” Water Resour. Res., 18(5), 1409–1423.
7.
Raudkivi, A. J., and Ettema, R. (1982). “Stability of armor layers in rivers.” J. Hydr. Div., ASCE, 108(9), 1047–1057.
8.
Raudkivi, A. J., and Ettema, R. (1985). “Scour at bridge piers in armored beds.” J. Hydr. Div., ASCE, 111(4), 713–731.
9.
Shen, W. S., and Lu, J.‐Y. (1983). “Development and prediction of bed armoring.” J. Hydr. Engrg., ASCE, 109(4), 611–629.
10.
Shields, A. (1936). “Anwendung der ähnlichkeitsmechanik und der turbulenzforschung auf die geschiebebewegung.” No. 26, Mitteilung der Preussischen Versuchsanstalt fur Wasserbau und Schiffbau, Berlin, Germany (in German).
11.
Taylor, B. D., and Vanoni, V. A. (1972). “Temperature effects in low‐transport, flat‐bed flows.” J. Hydr. Div., ASCE, 98(8), 1427–1445.
12.
Wilcock, P. R., and Southard, J. B. (1988). “Experimental study of incipient motion in mixed‐sized sediment.” Water Resour. Res., 24(7), 1137–1151.
13.
Wörman, A. (1991). “Interfacial sediment transport.” Bulletin No. TRITA‐VBI‐152, Dept. of Hydr. Engrg., Royal Inst. of Tech., Stockholm, Sweden.
Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 118 • Issue 3 • March 1992
Pages: 496 - 501
Copyright
Copyright © 1992 ASCE.
History
Published online: Mar 1, 1992
Published in print: Mar 1992
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.