A NUMERICAL STUDY ON THE EFFECT OF BEACH NOURISHMENT ON WAVE OVERTOPPING IN SHALLOW FORESHORES

Tomohiro Suzuki, Toon Verwaest, William Veale, Koen Trouw, Marcel Zijlema

Abstract


In this paper, the effect of beach nourishment on wave overtopping in shallow foreshores is investigated with the non-hydrostatic wave-flow model SWASH. Firstly, the applicability of SWASH to model wave overtopping is tested by comparing results with a physical model setup with different storm wall heights on top of an impermeable sea dike. The numerical results show good agreement with the physical model. After validation, sensitivity analysis of the effect of beach nourishment on wave overtopping is conducted by changing bottom configurations with the SWASH model. From the sensitivity analysis, it becomes clear that wave overtopping discharge in shallow foreshores is characterized by the bores generated in surf zone due to wave breaking. To reduce wave overtopping discharge in shallow foreshore, it is important to reduce the horizontal momentum of the bores.

Keywords


SWASH model; beach nourishment; wave overtopping; infragravity waves; bores; shallow foreshores

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