Empirical Formulas for Estimating Overtopping Discharge and Wave Force of Recurved Parapets Placed on the Crest of Rubble Mound Breakwaters

This study quantitatively analyzed the efficiency of wave overtopping reduction and the characteristics of wave pressure for recurved parapets on rubble mound breakwaters by conducting physical model experiments. The experiments were performed in a wave flume under various water depths and wave conditions to examine the effects of parapet height and curvature depth on overtopping rates and pressure distribution. The results indicated that the overtopping discharge significantly decreased as the depth of the recurved parapet increased, whereas the local wave pressure on the recurved parapet increased substantially. Based on these findings, an adjustment factor (γR) for the EurOtop (2018) formula is proposed, together with an empirical formula for wave force estimation that accounts for the force enhancement effect relative to vertical parapets. The proposed formulas are expected to serve as valuable tools for evaluating the overtopping performance and structural stability of recurved parapets in engineering design.