Wave Overtopping on Vertical and Composite Breakwaters

After an extensive series of 2-D model tests on the overtopping response of various caisson breakwaters, general conceptual design formulae and graphs have been derived which relate the mean discharge with the relative freeboard. The influence of geometrical changes is described by reduction factors with reference to the pure vertical structure. A simple correlation has been made with the overtopping performance of sloping structures. Overtopping volumes per wave were also measured and fitted with a universal probability function; their effects on model persons and cars behind the crownwall were statistically evaluated, thus allowing an upgrading of the existing criteria for the admissible overtopping on breakwaters.