Impact of a Quayside Floating System on Overtopping

Abstract

This paper reports results of the impact of a quayside floating system on overtopping. The approach is experimental and analytical. Rectangular floaters in heave motion were considered at various distances from a vertical wall. Floaters with different widths and heights were tested. The effect of the draft and the floater’s distance to the wall on overtopping quantification was considered in intermediate water conditions. First, overtopping evolution as a function of the wave period was found to be correlated with the floater behavior. The overtopping increased at the resonance period of the floater but decreased at larger periods. The experimental results were then compared with a linear analytical model based on potential flow theory, where the wave height at the seawall was given using the Van der Meer formula. An improvement of the analytical model was obtained by introducing a term corresponding to pressure losses between the floater and seawall. The experimental results are in good agreement with the corrected analytical model: the evolution is similar, with an averaged standard deviation of 1.2 for large wavelengths. The present results show that the wave period and distance of the floater to the vertical wall are significant parameters for overtopping. Overtopping is reduced by the presence of the quayside floater for small distances to the vertical wall and large wave periods when the floater follows waves.