MODELLING SCOUR IN FRONT OF DUNE REVETMENTS IN A SURF-BEAT MODEL

Pieter F. C. Van Geer, Jaap S.M. Van Thiel de Vries, Marien Boers, Joost P. den Bieman, Robert T. McCall

Abstract


This paper presents adaptations to the XBeach model aimed at including the relevant processes for the generation of scour holes at the toe of a revetment. Dutch assessment rules for the safety of sea defenses need to be adjusted to cope with a combination of sandy dunes and hard elements. To that end, the XBeach model is prepared to be incorporated in the assessment rules. Until now, XBeach did not model scour hole development in front of dune revetments accurately. We suggest to include the advection of turbulence as well as the effect of backwash of short waves that creates additional turbulence in the model. Verification with three physical model experiments shows that with the suggested adaptations of the model a scour hole with significant depth can be modeled.

Keywords


dune erosion; XBeach; scour; dune revetment

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References


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DOI: https://doi.org/10.9753/icce.v34.sediment.43