Analysis of municipal bridge deterioration factors using machine learning considering social data

Abstract

Bridge deterioration in Japan is advancing, and in Hokkaido, about 20,000 bridges are municipally managed under limited personnel and budgets. This study uses GIS to analyze spatial deterioration trends based on inspection data and examines the impact of geographical, environmental, and social factors on bridge health. The results show that "year of construction, road management municipality, and superstructure (material used)" are key deterioration factors, with trends varying by bridge type. Notably, RC bridges are more affected by municipal financial capacity and staff numbers. As they are often small and infrequently used, municipalities with tight budgets may delay repairs and maintenance.