Research on influence of sun glare in urban tunnels based on cellular automaton model in the framework of Kerner’s three-phase traffic theory

Abstract

As ventilation shafts set at the top of urban tunnels becomes a common pattern for ventilation, the sunlight cast under the shafts could cause sun glares which negatively affect the driver’s visual performance. In this paper, the influence of sun glare on individual drivers in urban tunnels is quantitatively illustrated by the change rate of driver’s pupillary area. Then random choice model of deceleration behavior in response to sun glare (DBSG) is established. The DBSG in urban tunnels is incorporated into the well-known KKSW (Kerner–Klenov–Schreckeneberg–Wolf) CA model and a new cellular automata model, KKSW-UT (urban tunnels) CA model is proposed. By means of the numerical simulation, traffic flow characteristics in urban tunnel are studied in the framework of Kerner’s three-phase traffic theory. And the frequency and severity of rear-end conflicts in urban tunnels are analyzed to study the influence of DBSG on traffic safety. Based on the results, it is found that DBSG can negatively influence both the traffic operation and safety.