Analysis on causes of four-wheeled vehicle accidents in hilly and mountainous area

Abstract

In previous report, four-wheeled vehicle accidents in hilly and mountainous area are paid attention to Nagano Prefecture. These accidents are vehicle alone or head-on collision accidents caused by lane departure on the road with up and down slope and curve. This paper researched the risk of accidents using statistical data analysis related to road alignment. Furthermore, the authors investigated additional accident cases in hilly and mountainous area occurred in 2016. and reconstructed the accident using accident simulation to find out the influence of road alignment. In results, the risks of accidents, which are calculated the number of fatal accidents divided by the number of all accidents, at downhill with right curve and uphill with left curve in Nagano are higher than those in the whole of Japan. These accidents were caused by lane departure, and the vehicles fell to the outside road. The occupants died with multi-injured body parts by these accidents. The accident reconstruction simulation indicates the road slope affects the curve recognition time. Therefore, the road alignment becomes accident hazard factor, and is sure to indicate accident hazard map to prevent accidents in hilly and mountainous areas.