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You are here : eLibrary : IAHR World Congress Proceedings : 32nd Congress - Venice (2007) : THEME A: Engineering and Management of Fresh-water Systems : The influence of the grain size distribution of unimodal and bimodal sediments on the resistance of...
The influence of the grain size distribution of unimodal and bimodal sediments on the resistance of channels with an alluvial bed
Author : Vajapeyam. S. Srinivasan , Hugo. M. Alcāntara, Valter. R.G. Medeiros
This paper presents an analytical and experimental study of the influence of the grain size distribution within the bed sediment mixtures on the hydraulic resistance of erodible bed channels. The experimental investigation considers both unimodal and bimodal sediment mixtures. Based on the resistance law for a rough surface, a new simple functional relationship is defined that takes into account the form roughness of each type of bed form separately. This functional relationship was established experimentally for three different mixtures of unimodal sediments that had the same mean diameters but different grain size distributions, as well as, three different bimodal mixtures with different mean sizes. The experiments were conducted in a recirculating laboratory flume. The results show that the size distribution and the nature of the sediment mixture affect the resistance relationship. The proposed functions have the advantage of not necessitating the separation of total roughness as surface roughness and form roughness.
File Size : 141,992 bytes
File Type : Adobe Acrobat Document
Chapter : IAHR World Congress Proceedings
Category : 32nd Congress - Venice (2007)
Article : THEME A: Engineering and Management of Fresh-water Systems
Date Published : 01/07/2007
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