IAHR Document Library

« Back to Library Homepage « Journal of Hydraulic Research 2001 Issue 2

Beginning of sediment transport of incoherent grains in shallow shear flows

Author(s): Marco Pilotti; Giovanni Menduni

Linked Author(s):


Abstract: In this paper the main results of an experimental investigation on the beginning of sediment transport of incoherent granular materials in shallow viscous flows are presented. The experiments, performed in a laboratory flume in both laminar and smooth turbulent flow conditions, complement the data already available in literature, and confirm that the hyperbolic trend shown by the Shields curve when the grain Reynolds number X decreases to zero is not supported by experimental evidence. In addition, they confirm the Yalin and Karahan (1979) hypothesis on the existence of a distinct curve for the inception of sediment transport in viscous dominated flows. On the basis of the observed phenomenology, we propose to interpret the process as a function of the probability distribution of the repose angle of the grains of the erodible bed. Accordingly, a simple mechanical relation is derived that explains the pattern exhibited by the experimental data.


Year: 2001

Copyright © 2022 International Association for Hydro-Environment Engineering and Research. All rights reserved. | Terms and Conditions