STUDY ON EROSION PROCESS OF ARTIFICIAL BEACH IN KEMIGAWA

In this paper, the results of the field survey on the coastal erosion at Kemigawa beach as the artificial beach are presented, and causes of the erosion are discussed using the sea conditions and the grain-size distribution of sands of the beach. The results of the investigation are summarized as follows:(1) The erosion at Kemigawa beach is intense compared with neighbor artificial beaches that has a characteristic like the Kemigawa beach.(2) The result of the numerical analysis using the cross section of the construction plan shows that the wave conditions of near shore at Kemigawa beach is calmness in the stormy weather.(3) The results of the grain-size analysis of sands show that the small-size sands that flow away from the center of Kemigawa beach maybe deposit at the base of the breakwater.(4) The result of the comparison between d50 of the sands and the gradient of the foreshore about the construction plan of Kemigawa beach shows that the beach has the tendency of the erosion.