Kinematics of waves propagating and breaking on a barred beach

Laboratory experiments are conducted in a wave facility with a loose sediment beach in order to estimate the wave characteristics needed for sediment transport modeling. A roller model and a Boussinesq-type model are used for comparing and discussing the experimental results. It is shown that the velocity skewness and acceleration skewness evolutions along the beach profile can be estimated from measurements of surface elevations. The roller model correctly reproduces the set-up and undertow measurements as long as the cross-shore variations of the second-order moment of the free surface displacement are taken into account. The Boussinesq model correctly reproduces the wave non-linearities with some discrepancies in the breaking region over the bar topography.