A model for unsteady sediment transport in degrading alluvial channels

V Sarda, R Dhiman, R Calay

Abstract


The collection of data for unsteady/non-uniform sediment transport rates in a river below a reservoir, which arrests sediment from upstream, is very difficult. The establishment of a model for the determination of these sediment transport rates is equally difficult but important for the safety of a structure below the reservoirs. An indirect technique based on continuity equation for sediment transport has been used to obtain such data for unsteady/non-uniform flow conditions. Based on these data and dimensional analysis, a relationship for determination of sediment transport rate below high capacity reservoirs under unsteady-non-uniform conditions has been proposed which gave very high efficiency when checked with the available data for such conditions. As a consequence, a relationship for extent of degradation has also been established.

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References


Garde, R. J. and Ranga Raju, K. G. (2000) Mechanics of sediment transportation and alluvial stream problem, New Delhi: New Age International (P) Ltd.

Gessler, J. (1971) Aggradation and Degradation. Ins.H. W. Shen (Editor) River Mechanics Vol. 1, Ch. 8, Publisher H. W. Shen, Fort Collins, Colorado.

Komura (1961) Bulk properties of river bed sediments and its application to sediment hydraulics, Proc. Japan National Congress for applied mechanics.

Newton, T. (1951). An Experimental Investigation of Bed Degradation in Open Channel Flow. Trans. Boston Society of Civil Engrs, pp. 28-60.

Sarda, V. K and Soni, J. P. (1984). River bed degradation below high capacity reservoir, J. of Institution of Engineers (India), Vol. 64, pt CI6, May, 354-360.

Soni, J. P. (1975). Aggradation in streams due to increase sediment load", Ph. D., Thesis, University of Roorkee, Roorke (UP).

Suryanarayana, B. and Shen, H. W. (1971). Laboratory Study of Degradation and Aggradatio, Journal of Waterways, Harbour Coastal Engg. Division, ASCE, Vol. 27, No. WW-4, 615-630.

Task Committee on the preparation of the Sedimentation Manual (1971), Sediment transport mechanics F. Hydraulic relations for alluvial Streams, J. Hydraulic Div., ASCE, Vol. 97 No. Hy 1, 101-141.




DOI: http://dx.doi.org/10.1260/1750-9548.4.1.21

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