ABSTRACT
A small-scale physical model was build and used to study deposition processes in a planned debris basin in the French Alps. Numerical simulations were then undertaken with a 2D depth-averaged hydraulic and morphologic numerical model in order to check its capability to reproduce flow and bed changes in this steep and laterally unconfined case with coarse sediment. The paper focuses on the set-up of the numerical model, which enables to get results very similar to the physical model. Old and state-of-the-art formulations for friction law and for bedload transport equation were compared. More precisely, the best performance were obtained with a friction law valid for small relative flow depth and bedload transport formulation using a non-threshold equation.
