Dam-Break waves over mobile bed

Dam-break waves are a major concern for communities and infrastructures in flood-prone areas. The impact of dam-break waves against rigid obstacles after propagation on a mobile bed is lacking both in experimental datasets and in numerical investigations aimed at assessing the capabilities and limitations of available morphodynamic models. To fill these gaps, a novel data set from experiments of dam-break waves propagating over an erodible bottom and impacting over a vertical wall is presented and compared with numerical simulations performed by the Saint Venant–Exner model. First, the effects of bottom mobility are discussed by comparison with the corresponding fixed bed condition. Then, supplementary conditions are investigated for different initial water levels and reservoir lengths. The comparison with the results of the numerical simulation shows that the relatively simple model employed is able to reproduce the general features of the process and the peak impact force with reasonable accuracy. •Dam-break waves impacting a wall are studied in fixed and mobile bed conditions.•A novel data set of laboratory experiments is provided.•The peak value of the impact force is slightly greater under mobile bed conditions.•The SVE numerical model reasonably predicts the general features of the phenomenon.