The solitary wave run-up on sloped beaches protected by submerged rigid breakwaters

Abstract

The reduction of wave run-up induced by solitary waves at sloping beaches, by means of submerged barriers has been investigated. To this purpose, 198 laboratory tests were undertaken in the wave channel of the University of Calabria, by adopting three beach slopes, three water depths and square and rectangular rigid type-barriers. To make comparisons on the performance of the barriers in reducing the run-up, 99 tests were carried out considering the same experimental conditions, without the barriers. Two approaches were used to deduce the resulting solitary wave run-up in the presence of the barriers starting from the knowledge of wave parameters without them. The first approach uses the wave amplitude, whereas the second, more physically based, uses the wave energy, depending on the horizontal velocity and the wave pressure. Based on the calculation of the transmission coefficients using the dimensional analysis, the transmitted wave amplitude and energy after the barriers were deduced. Using these quantities, the recent semi-empirical formulas deduced by Casella et al. (2022) in the absence of the barriers were extended to determine the solitary wave run-up in their presence.