Wave Run-Up on and Wave Overtopping over a Prototype Rubble Mound Breakwater

Many physical processes concerning the land-ocean interaction are not yet fully understood. Wave run-up and wave overtopping are very important in the design of sloping coastal structures such as breakwaters, sea walls, dikes,... Nowadays, the design of these coastal structures is solely based on small scale model tests. Previous research indicated that wave run-up on rubble mound breakwaters might be underestimated by these small scale model tests. Therefore, wave run-up and wave overtopping on a prototype rubble mound breakwater are studied in detail. A clear difference between prototype measurement results and small scale test results is noticed. Prototype measurements show wave run-up values which are up to 40% higher than the values obtained by small scale laboratory tests. Moreover, the dimensionless run-up value is dependent on the water level: when the water depth decreases, valuesincrease from 1.80 at high tide up to 2.25 at mean tide. These valuesare much higher than the values found in literature and used as a designrule.