This paper investigates cross-shore profile changes of coarse-grained beaches, with particular regard to discussing the tendency for onshore transport and profile steepening in the swash zone. The discussion includes observed morphological changes on a gravel beach from experimental investigations at the Large Wave Flume (GWK) in Hanover, Germany. We investigate the profile evolution evaluating the transport rates from a bed-load sediment transport formulation coupled with velocities calculated from a set of Boussinesq equations. We discuss the influence of bottom friction on the predicted profiles and the use of non-symmetric C-values for the swash phase in the sediment transport equation. This is done to elucidate the processes that are involved in the morphological response of these beaches. Physical mechanisms believed to be important are: infiltration effects on the flow above the beachface, the more accelerated flow in the uprush and the bore collapse from a plunging breaker.
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