Abstract
A slit-caisson is known as a typical wave-absorbing-structure with a vertical front face. The design wave force on the slit caisson is usually estimated by the empirical formula, for instance the modified Goda formula. In this study, the perforated wall type caisson consisting of angular members in it's front was adopted as a model caisson. We have carried out the experiment on wave forces on the model caisson very precisely to rationally estimate the design wave forces. Characteristics of local wave force on each member of the model caisson, say wave forces on the front wall etc., were examined experimentally. For the practical design, the similar wave force analysis to the previous method for a slit caisson was also applied to specify the modification coefficient of the wave force given by the Goda formula.