EFFECTS OF DIFFERENT ARMOUR UNITS AND PLACEMENT METHODS ON WAVE LOADS ACTING ON CROWN WALLS

Numerous previous experiments aimed to clarify and predict the detailed mechanism of wave forces on crown walls of mound breakwaters. However, a comprehensive study has not yet been conducted for cases involving different placement methods and packing densities of armour units. This study examines how various placement methods and packing densities of tetrapod and Antifer units, in combination with natural rocks in the armour layer design, influence the distribution of wave forces on the crown walls. Physical model tests were carried out using 1:1.5 and 1:2 face slopes, allowing for modifications to model units in the armour layer and a comparison of changes in wave-induced forces experienced by the crown wall. As a result of the study, the empirical coefficients of Pedersen (1996) formulae adjusted by Norgaard et al. (2013) for shallow water condition were modified for Antifer and tetrapod units.