Abstract
The damage of armor blocks occasionally occurs at the toe of a mound foundation of a breakwater although the block weight is larger than the one calculated by the Hudson's formula. This paper aims to elucidate the factors that influence on the stability of armor blocks at the toe of the mound foundation by conducting 3D hydraulic model experiments with field topography. The 3D experimental results revealed that the change of flow induced by the existence of the armor block has a great effect on the stability of the block in the same way as the previous 2D experimental results. The incident wave angle and a tidal level was also found to affect the block stability.
