Abstract
A movable-bed experiment with a scale model of 1/50 was carried out to investigate the function of an L-shape groin. As a measure to reduce the construction cost of an L-shape groin, the reduction in the number of the concrete blocks to protect the upcoast side of the groin and the removal of part of the breakwater connecting the tip of the groin to offshore breakwater were investigated. Finally, it was concluded that the reduction of part of the breakwater was possible, and the landward end of the groin was not exposed to waves, even when extraordinarily high waves are incident to the coast, suggesting no need to protect the landward end of the groin.