Japan's coastal protection facilities were developed with the intention of protecting those cities behind the coastline from natural disasters such as high water, tidal waves, tsunamis and erosion. The majority of these facilities were constructed until the 1960s and hence have suffered damage and deteriorated functioning due to aging of materials and the force of the waves. This being the situation, the government and various local bodies must work within their straightened fiscal circumstances to effectively diagnose the degree of degradation, improve functioning as appropriate and perform maintenance. This study has ordered the relationships between the causes of the facilities deformation and the countermeasure construction methods as well as verifying their validity, thus enabling the correct countermeasure construction methods to be selected.
