Investigation on the impact of combined sight induction facilities inside highway tunnels on vehicle operation characteristics

To investigate the impact of combined sight induction facilities on vehicle operational characteristics in highway tunnels, two experimental schemes are designed, one with and one without such facilities. Real vehicle experiments are conducted in the Yunling Tunnel, collecting traffic flow data. The study focuses on two key indicators: average speed and lateral lane deviation, analyzing their relationship by building a regression fitting model. The results demonstrate that within highway tunnels, the combined sight induction facilities effectively reduce vehicle speed and decrease the degree to which vehicles deviate from the lane centerline. A positive correlation is found between lateral lane deviation and average speed in highway tunnels. The combined sight induction facilities contribute to enhanced traffic safety and driving stability in the tunnel environment. The findings provide a solution for evaluating and optimizing combined sight induction facilities in tunnels, while the constructed regression fitting model reflects the trend of vehicle operational characteristics in tunnels, offering theoretical support for future improvements.