Analysis Of The Overtopping Layer Thickness On Low-crested Mound Breakwaters

Abstract

In recent years, mound breakwater design has had to consider social concerns about the visual impact of coastal structures as well as the rise in sea levels due to climate change. Additionally, mound breakwater design must consider pedestrian safety when facing overtopping loads and the subsequent hazards. The overtopping hazard on dikes has been studied considering the overtopping velocity and the overtopping layer thickness on the crest. This paper proposes a new method to estimate the overtopping layer thickness on the crest of mound breakwaters based on 123 physical tests of conventional low-crested mound breakwaters with three different armors. The new method is based on formulas given in the literature to estimate wave run-up for mound breakwaters and overtopping layer thickness on the crest of dikes which was exceeded by 2% of the incoming waves, but using the roughness factors 0.33 (Cubipod ®-1L), 0.48 (rocks-2L) and 0.35 (cubes-2L) and the empirical coefficients 0.51 and 0.89. The new method explained 79% of the variance in the observed overtopping layer thickness exceeded by 2% of the incoming waves (rMSE=0.21).