Towards Sustainable Road Network in the Era of Shrinking Population: Case Study Using MATSim

Assuming an aging society where the number of expressway users decreases and maintenance costs for infrastructures remain high, we propose a new method for analyzing whether expressway routes should be closed when their cost-benefit ratios deteriorate owing to decreases in users. As a case study, we analyzed the Kawasaki route (the Kanagawa No. 6 Kawasaki route of the metropolitan expressway in Japan) according to the proposed method. It was found that the costbenefit ratio of the route would be less than 1 in 2025 owing to the decrease in users. However, if the Kawasaki route was closed, the vehicles there would run on National Route 409 as an alternative route, and its congestion rate would increase significantly.