Empirical Analysis on Risky Behaviors and Pedestrian-Vehicle Conflicts at Large-Size Signalized Intersections

Abstract

In this study, we conducted observation surveys and analyzed the risky behavior of both pedestrians and vehicles making left turns at five major intersections in Japan (left hand traffic system). We aggregated the number of risky behavior of pedestrians and clarified the factors by developing a linear regression model. It is found that if the setback distance of the inflow leg is inappropriately-long, pedestrians tend to exhibit a risky behavior after pedestrian green flashing. We also quantified the risky movements of vehicles making left turns and explained the factors using linear discriminant analysis. For left-turning vehicle, if setback distance of outflow leg is long or the curvature radius of the corner curb is gentle, the vehicle tends to not drive slowly when entering an intersection. In addition, we adopted the estimated post encroachment time (EPET) as a surrogate index to evaluate the risk of conflict between pedestrians and vehicles making left turns. At final third part of corner curb, it was clarified that the wider crosswalk relates to safe situation, however, the larger curvature radius of the corner curb relates to severe conflict. Furthermore, we discussed safety countermeasures for pedestrians by using the results of the sensitivity analysis.