Simplified Model for Pedestrian-Vehicle Interactions at Road Crossings Based on Discrete Events System

Road accident reports show that many accidents involve pedestrians, the category of road users generally considered "weak" with respect to other mobility users, and that these accidents occur at pedestrian crossings. Therefore, traffic engineers need simulation tools that can forecast the results of a given design solution and compare the solution with alternatives. A simplified model that simulates interactions between pedestrians and vehicles at road crossings is presented. In the model, the crossing process is represented as a discrete events system, and the model uses basic and easy-to-collect parameters to estimate interactions. Pedestrian behavior in the decision phase is characterized with a gap acceptance criterion, which is based on parameters derived from probabilistic distribution and takes into account the heterogeneity of the pedestrian population. Interaction between pedestrians during the crossing phase is taken into account with a cellular model of the crossing area. The model allows estimation of safety benefits for pedestrians and crossing level of service for both pedestrians and vehicular flows, starting from site geometry and field measurements of flow parameters of pedestrians and vehicles. The model was applied to a real site in a case study. The effects of traffic-calming interventions were also simulated and evaluated.