CHARACTERISTICS OF SOLITARY WAVE BREAKING INDUCED BY BREAKWATERS

Laboratory experiments are presented for the breaking of solitary waves over breakwaters. A variety of behaviors is observed, depending on both breakwater and incident wave height: for emerged breakwaters, waves may collapse over the crown, or break backward during rundown; and for submerged breakwaters, waves may break forward or backward, downstream of the breakwater. The limit of overtopping and wave transmission and reflection coefficients are experimentally determined. It is seen that transmission is large over submerged breakwaters (55-90%), and may also reach 20-40% over emerged breakwaters. Computations using a fully nonlinear potential model agree well with experimental results for the submerged breakwaters, particularly for the smaller waves (H/d < 0.4). For emerged breakwaters, computations correctly predict the limit of overtopping, and the backward collapsing during rundown.