Abstract
The purpose of this study is to obtain basic knowledge for a design that considers the reinforcing effect of Counter-Weight Block (hereinafter referred to as "CWB") reinforcement embankment against the overturning of a breakwater. We investigated the effect of different cross-section figures and structures of CWB reinforcement embankment on the reinforcing effect against overturning using centrifuge model tests. The results indicated that a staircase cross-section figure is desirable for the CWB reinforcement embankment. However, when the caisson wall and the CWB reinforcement embankment are in close contact, a gap will form between the caisson wall and the CWB reinforcement embankment after the first overturning action. Consequently, the resisting moment at the initial stage of the second and subsequent overturning actions becomes minimal. It was shown that the use of filling stones between the caisson wall and the CWB reinforcement embankment in advance contributes to improving the reinforcing effect against repeated overturning actions. However, the challenge with large-scale overturning is that the crown height of the filling stones gradually decreases, and the reinforcing effect becomes smaller.
