SEDIMENT TRANSPORT CAPACITY -AN IMPROVED BAGNOLD FORMULA

This paper re-examines Bagnold＇s theorem of sediment transport. Different from the stream power defined by Bagnold, i.e., τoV, this study shows that the total load of sediment-laden flow, gt, is related to near bed energy dissipation rate, i.e., τou＊. An attempt is made to explain the empirical relation. The ratio （=k） of measured total load, gt, to the product of near bed velocity, u＊, and energy dissipation rate, τoU＊, is analyzed. It is found that k is independent of the Rouse number, Z, if Z is greater than 2.6, but the coefficient k decreases with the increase of Z when Z 〈 2.6. An empirical relation between k and Z is developed. A systematic and thorough analysis of 1,458 sets of data collected from 16 rivers and canals confirms that the proposed formula can be used to compute the total load with accuracy.