Effect of Motorcycle Proportions on Accident Risk in Mixed Traffic

抄録

Motorcyclists comprise a significant proportion of the mixed traffic in Southeast Asia. However, few studies have examined the effect of the motorcycle proportion on accident risk. This study utilized a microscopic traffic simulator and applied a zero-inflated negative binomial regression model to analyze the relationship between traffic composition and accident risk. The results demonstrated an inverse relationship between motorcycle proportions and the normalized average frequency of critical TTC (FCT) in two-lane two-way undivided roads, whereas a positive relationship was observed in four-lane and six-lane divided roads. Moreover, this study identified the significant influences of signalized intersections and access density on the normalized average FCT. These findings emphasize the need to address the critical situations that lead to rear-end crashes for specific road types. By bridging this research gap, this study provides valuable insights for developing effective road-safety strategies in Southeast Asian countries, where mixed traffic prevails.