Investigating the Influencing Factors of Vehicles’ Lateral Position Stability on Expressway

Traffic safety on expressway has received increasing attention, and vehicle lateral position deviation is one of the key risk factors causing expressway traffic accidents. Exploring the influencing mechanism of different factors on vehicles’ lateral position stability is therefore important for ensuring traffic safety and refined management of expressway. Taking Guangzhou-Shenzhen Expressway as an example, vehicles’ lateral position and driving characteristics passing by a specific location were collected. Based on the observation data, a comprehensive analysis of vehicles’ moving characteristics and the distribution of vehicles’ lateral position were conducted. Then a quantile regression (QR) model is built to further explore the potential influence of various factors on vehicles’ lateral position shifts. Based on the results, there is a higher possibility for left shift of vehicle lateral positions and vehicle speed has a significant negative effect on the lateral position shift of small-sized and medium-sized vehicles. Suggestions for refined traffic management and control to enhance safety driving on expressway are then proposed.