Abstract
This paper describes the behaviours of suction foundations used for breakwaters during wave actions, mainly about pore water pressures and stresses in the foundation soil. The study has been conducted with the large hydro-geo flume which can generate waves of 3.5m and with a two dimensional finite element program based on the elastic theory, which can estimate the behaviours of pore water pressures and stresses in the foundation soil as well as super structure's displacements under wave action. The study has revealed that negative pore water pressure generates inside the suction foundation during wave action and contributes to the resistance of the breakwater against the wave action. And also the mechanism of the generation of the negative pore water pressure under horizontal loads is discussed.
