ABSTRACT

A soft landing breakwater was originally proposed for sites where the ground conditions are not good but wave conditions are rather mild (Kuchida et al. 1986). A key feature of the soft landing breakwater is its light self weight. As originally conceived, the horizontal resistance of this breakwater depends on the cohesion between the base plate and clay surface (Figure 1 a)) (MOT 1991). Usually, however, the horizontal resistance of this type is inadequate for wave forces, and piles are therefore used to improve its resistance capacity. This modification is called the piled type (Figure 1 b)) (MOT 1991). The mechanism of horizontal resistance in this type is rather complex because horizontal loads are borne not only by the base plate but also by the piles, and furthermore, the presence of piles may change the resistance mechanism of the cohesion between the base plate and the ground surface.