Statistically Derived Bedload Formula for Any Fraction of Nonuniform Sediment
Publication: Journal of Hydraulic Engineering
Volume 126, Issue 2
Abstract
Based on a method of combining stochastic processes with mechanics, a new bedload formula for the arbitrary kth size fraction of nonuniform sediment is theoretically developed by using a stochastic model of sediment exchange and the probabilistic distribution of fractional bedload transport rates. The relations, proposed recently by Sun, for the probability of fractional incipient motion and for the average velocity of particle motion are introduced to bedload formula. Plenty of experimental data for the bedload transport rate of uniform sediment are used to determine two constants. The theoretical bedload formula for any fraction of nonuniform sediment possesses several advantages, including a clear physical concept, a strict mathematical derivation, and a self-adaptability to uniform sediment. The formula is verified with natural data expressing the transport of nonuniform sediment under full motion in laboratory flume. The result shows that the experimental observations agree well with the predicted fractional bedload transport rates. Comparison of the theory with field data finds that the proposed formula still applies to partial transport of bedload in gravel-bed streams as long as the immobile percentage of bed material is taken into account.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Bridge, J. S., and Bennett, S. J. (1992). “A model for the entrainment and transport of sediment grains of mixed sizes, shapes, and densities.” Water Resour. Res., 28(2), 337–363.
2.
Bridge, J. S., and Dominic, D. F. (1984). “Bedload grain velocities and sediment transport rates.” Water Resour. Res., 20(4), 476–490.
3.
Einstein, H. A. (1950). “The bed load function for sediment transportation in open channel.” Tech. Bull. No. 1026, Soil Conservation Serv., U.S. Dept. of Agriculture, Washington, D.C.
4.
Leopold, L. B., and Emmett, W. W. (1977). “1976 Bedload measurements, East Fork River, Wyoming.” Proc., National Academy of Science, Washington, D.C., 74(7), 2644–2648.
5.
Misri, R. L., et al. (1984). “Bedload transport of coarse nonuniform sediment.”J. Hydr. Engrg., ASCE, 110(3), 312–323.
6.
Proffitt, G. T., and Sutherland, A. J. (1983). “Transport of nonuniform sediments.”J. Hydr. Res., IAHR, 21(1), 33–43.
7.
Samaga, B. R., et al. (1986). “Bedload transport of sediment mixtures.”J. Hydr. Engrg., ASCE, 112(11), 1003–1018.
8.
Sun, Z., and Zhu, Y. (1991). “On Einstein's bedload function.” J. Sediment Res., 1, 20–27.
9.
Sun, Z., et al. (1997). “Incipient motion of any fraction of nonuniform sediment.”J. Hydr. Engrg., Beijing, 10, 25–32.
10.
Swamee, P. K. (1991). “Bedload and suspended load transport of nonuniform sediments.”J. Hydr. Engrg., ASCE, 117(6), 774–787.
11.
Zhang, R., and Xie, J. (1990). River sediment dynamics. Water Resources & Electric Power Press (in Chinese), Beijing, China.
Information & Authors
Information
Published In
History
Received: Jun 2, 1998
Published online: Feb 1, 2000
Published in print: Feb 2000
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.