Abstract
A series of hydraulic model experiments was systematically and carefully carried out to estimate the stability of various types of armor units for harbor-side rubble mound of composite breakwater against tsunami flow overtopping the crest of the caisson.
As a result, the following points were carified: Damage to armor units is strongly dependent on the position of the flow. Armor stones of weight 1 ton are easily removed by the tsunami flow. Flat type concrete blocks with well-arranged holes showed high stability. Fixed armor units placed on the toe of the slope enhanced the total stability of the armor layer.
