Transport Capacity of Overland Flow for Sediment Mixtures

Abstract

AbstractSediment transport capacity of overland flows is crucial to understanding and modeling the erosion and deposition processes. The transport capacity for sediment mixtures is particularly complex because of the need for an algorithm to allocate the total available shear stress or stream power to individual size classes. The transport capacity for sediment mixtures may not even be unique, depending on whether the flow is eroding or depositing sediments unless all sediments are of a single size class. Using data from a set of flume experiments involving steep slopes and high sediment concentrations, a formula was proposed for the sediment transport capacity limited by available stream power and available accommodation space for sediments. Sediments used for the experiment were further sieved into five distinct size classes. The sediment transport capacity was measured for 25 flow-slope combinations to validate a new formula for individual size classes, and to propose and test a method to compute the s...