A Simulation-based Traffic Safety Evaluation of Signalized and Un-signalized Intersections

In many cases, crashes at intersections account for over 50% of all urban road accidents. The need to reduce these crashes has fostered considerable research on the development and evaluation of traffic safety at intersections. This paper introduces a micro-level behavioral method for estimating crash potential at signalized and unsignalized intersections for different traffic characteristics. As long as Speeding is recognized as a major contributing factor in traffic crashes, in this study it is emphasized on the contribution of speed in traffic safety situation of intersections. In this study, proximal safety indicators which represent the temporal and spatial proximity characteristics of unsafe interactions and near-accidents are explored and then one of them is implemented in the safety evaluation process for unsignalized intersections and time headway for signalized intersections as a flow characteristic. Results show that an increase of speed limit on roads will end to a more dangerous situation. On the other hand the ability of microsimulator to evaluate safety effects of such policy measure like speed limit is proven.