Author(s): Rui M. L. Ferreira; Joao G. A. B. Leal; Antonio H. Cardoso
Linked Author(s): Rui M.L. Ferreira
Keywords: Dam-break; Sediment transport; Riemann problem
Abstract: The present work is concerned with the structure of the solution of the generalised dam-break problem, defined as the propagation of the dam-break flood wave over a cohesionless erodible bed. The conceptual model is based on a shallow-water approach with bed-load dominated sediment transport. Under this framework, the properties of each of the λ (p) -characteristic fields are analysed regarding non-linearity, monotonicity and entropy conditions are also object of analysis. It was found that the solution must be composed of one expansion wave and two shock waves, connected by two constant states if, initially, the sediment bed is discontinuous. If the initial sediment bed is continuous, the solution is composed by two expansion waves. Numerical finite-difference solutions and experimental evidence were used to verify the theoretical assumptions. It was found that the numerical results, in the form of characteristic paths, for each field and each conceptual situation, confirm the proposed model. It was also found that the numerical results agree well with the experimental data.
Year: 2001