Evaluation of overtaking manoeuvres on two-lane rural roads

Two-way two-lane roads constitute a major proportion of rural road networks in Iran. The work described in this paper aimed to investigate the factors that influence overtaking manoeuvres using traffic conflict techniques to collect field data related to dangerous overtaking. The process of data collection was conducted by means of video recordings and other heuristic methods using inductive loop detectors. As one of the most important underlying independent variables, the percentage of time spent following was simulated. The classification and regression tree method (a common data mining approach) was used to identify important variables and explore the cut points of continuous variables. No-passing distance, road width, mean speed and vehicle time spent following were identified as the most important variables, and the results indicated a direct relationship between no-passing distance and the number of dangerous overtaking manoeuvres. Road widths less than the standard values and an increase in mean speed were also found to lead to an increase in the number of dangerous overtakings.