Dynamic impact of a water and sediments surge against a rigid wall

The paper addresses the dynamic impact of channel flows of water and mixtures of water and sediments on a test wall. Two types of impact may occur: the first characterized by the formation of a complete reflected wave moving upstream; the second type consisting in the vertical deviation of the flow along the wall with a jet-like behaviour. The paper deepens this second type of impact. During the impact of the flow against the wall, the pressure distribution along the wall and the impact force were measured. In order to explain the phenomenon, a rational approach based on the conservation equations for mass, momentum and energy was adopted; from this approach some simplified solutions were derived. We discuss the possible effects of the impact of single gravel particles and the influence of the dimensionless groups that govern the phenomenon. A good agreement between the experimental data and the results of the theoretical approach was obtained.