The operational efficiency and safety of pedestrian flows at intersections is an important aspect of urban traffic. Particularly, conflicts between pedestrians and vehicles in crosswalk are one of the most influential factors for intersection safety. This paper presents a cellular automata model that simulates pedestrian and vehicle crossing behaviors at signalized intersections. Through the simulation, we investigate the effects of different pedestrian signal timing and crosswalk widths on the crosswalk capacity, the number of traffic conflicts between pedestrians and vehicles, and pedestrian delay due to the conflicts. The simulation results indicate that the cellular automata is an effective simulation platform for investigating complex pedestrian-related traffic phenomenon at signalized intersections. 1. Introduction Intersections are the basic joints of urban roads, through which multidirection traffic flows pass. Thus, traffic conflicts and crashes are prone to happen at the intersections. In China, the mixed traffic flow is one of the typical characteristics of urban road traffic. Pedestrians account for a great proportion in the intersection traffic and they are vulnerable road users who have to face long crossing distance that increases exposure to conflicts with intersecting vehicles. Even worse, the time for pedestrians to finish their crossing is often insufficient due to the large intersection size and heavy pedestrian traffic demand. So, the potential conflicts between pedestrians and vehicles may lead to traffic crashes, resulting in injuries and fatalities more likely for pedestrians. According to the statistics, about one-third of the road traffic crashes in China are directly associated with pedestrians and about 25% of the accident death tolls are from pedestrian traffic [1]. Besides, the traffic conflicts can also cause delay problem, which decreases the efficiency of road traffic to a certain extent. Therefore, it is practically meaningful to study the conflicts between pedestrians and vehicles at intersections. Better understanding the generation mechanism of traffic conflict at intersections can contribute to investigating the causation of traffic crashes. Perkins and Harris [2] first defined traffic conflict as “an interaction between two or more road users and an incident that induces the avoidance behavior of road users to avoid an imminent accident.” A formalized definition of traffic conflict was later adopted as “an observable situation in which two or more road users approach each other in space and time for such an extent
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