Large-scale morphodynamics structures in the Arc en Maurienne River (France)

摘要

This work focuses on the morphodynamics of a system of alternate gravel bars in an engineered mountainous alpine river, the Arc en Maurienne (France). The experimental site is a selected long reach, which evolved from a natural braided pattern into a reach constrained by two longitudinal dikes, with a curve acting as a forcing point on the sediment motion. The channel's width variation also affected its morphology, leading to the formation of an alternate bar system. Numerical results shows that the Telemac-Mascaret modelling system (TMS) is able to reproduce the morphodynamics behavior observed in a gravel bar-scale reach (approx. 1 km) and the alternate bar patterns observed in an 8 km river reach of the Arc en Maurienne River.