Numerical modelling of sediment bed aggradation in open rectangular drainage channels

A numerical modelling investigation of bed aggradation in open rectangular drainage channels is presented in this paper. A semi-coupled modelling approach for uniform sediments based on 1D-shallow water De Saint Venant - Exner equations was adopted to describe the temporal evolution of the bed in the deposition and transport phenomena associated with aggradation process. Six well-established sediment transport formulas were used to evaluate the sediment discharge over the aggrading bed. Simulations enabled the comparison of results obtained with the selected formulas against a comprehensive set of experimental measurements reported in the literature. Results have shown the adopted model to describe successfully the evolution of sediment bed and water level profiles during the aggradation experiments, with minor differences depending on the used sediment transport relationship.