Analysis and modeling time headway distribution on multilane highway considering climate conditions (Case Study: Sanandaj-Hamedan Highway)

The time headway is the time interval between passing two consecutive vehicles from a specific road index. This parameter is one of the important characteristics of traffic flow, which is very important in the study of simulation and traffic modeling. Traffic managers and engineers, in order to correctly plan in different situations, must have a thorough understanding of driver's behavior in adopting headway. Because the distribution of headway influences various flow parameters such as capacity, service level and safety. A careful analysis of the distribution of time headway also provides planners with the ability to simulate and generate micro models, reduce latency, and increase the capacity of the facility. Appropriate vehicle headway along the road, increasing safety and reducing the chance of accidents will result in more travel satisfaction. In this research, a study was conducted on the analysis and modeling of the time of vehicles in different climate conditions in the highway. The time data was analyzed with the aim of studying the weather conditions by lane, automobile pair, night and day and traffic volume from the grouped way and the models obtained from each group were analyzed. The results showed that, in general, the average of the time headway was higher in rainy conditions, and in most groups, the difference in mean headway in cases of heavy pursuit is more than the other.