2024 年 12 巻 1 号 p. 135-155
Due to budget constraints in the local cities of Japan, there is an urgent need to prioritize the maintenance or removal of aging transportation infrastructure, particularly bridges. Given the declining tax revenues, our study proposes an approach to systematically address this challenge. Using GIS network analysis, we evaluated the impact of bridge removal on the daily travel time of residents, considering the intricate road network and population distribution of the selected study area, Island A. Various public facilities on the island were identified as potential destinations. Our methodology assessed the changes in travel time for residents if a bridge was removed. Four distinct bridge removal scenarios were proposed: two prioritize minimal disruption in resident travel time, and the other two focus on the life-cycle costs (LCC) of the bridges. This analytical process aims to achieve a balance between fiscal responsibility and ensuring resident convenience. By proposing efficient bridge removal plans based on the consequences of each scenario, we hope to guide local governments in making informed decisions. Through this Japanese case study, our methodology offers valuable insights into formulating strategies for other developed areas facing similar infrastructure challenges.
