Effective variables on following behaviour of heavy vehicle drivers

Following behaviour of passenger car drivers has been modelled in many studies over the last half a century. However, the existence of heavy vehicles in the traffic stream has not received the same level of attention. Heavy vehicles drivers show different following behaviour which could be the result of the different characteristics of their vehicles. This difference can significantly influence the traffic stream characteristics. With attention to the increasing volumes of heavy vehicles, it is essential to examine how the future road networks can deal with heavy vehicles. This study uses detailed vehicle trajectory data recorded in congested traffic condition as a basis to analyse heavy vehicle drivers' vehicle-following behaviour. Two vehicle-following combinations are considered in this study in which a heavy vehicle follows either a passenger car (H-C) or another heavy vehicle (H-H). The influence of various traffic variables on this particular behaviour is investigated. The effective features are selected by using two different methods. The first one is scatter plots and linear regression method and the Second one is the stepwise regression method. The findings of this study serve as a guidance to develop a specific model to capture heavy vehicle drivers' following behaviour. The results also could be the interest of modellers attempting to replicate drivers' following behaviour in micro-simulation models and manage multiclass vehicle interactions.