Sliding Characteristics of Upright Section of Composite Breakwaters Covered with Wave-dissipating Blocks in Construction Stages

During the construction of composite breakwaters coverd with wave-dissipating blocks, impact wave forces may occur on upright sections of discontinuous wave-dissiipating areas. Sliding patterns of the upright sections due to such wave action were clarified by analyzing seven breakwater damages occurred from 1994 to 1996 in Hokkaido. These phenomena were reproduced by 2-D and 3-D hydraulic model tests, and the characteristics of the wave forces were clarified for typical structural and wave conditions. The effects of the extended length of upright sections and incident wave angles were proposed for the practical design procedures, and their validity were examined by the damage data