BEACH EROSION ON OHARAI-ISOHAMA COAST AND BEACH STABILIZATION BY GROINS AND BEACH NOURISHMENT USING COARSE MATERIAL

Abstract

 In recent years, beach has been eroded on the Oharai-isohama coast with the formation of a high scarp. Satellite imageries and bathymetric survey data were analyzed to investigate the beach changes of this coast. Measures have been studied by numerical simulation using the contour-line-change model considering the effect of change in grain size of bed materials. Because this coast is famous as a recreational park together with the fishing ground, beach nourishment using coarse materials was mainly considered as the measure. To prevent nourishment sand from discharging, groins were adopted as a measure to stabilize the nourishment beach.