Research On The Collaborative Setting Of Variable Speed Limit Signs And Visual Deceleration Markings In The Entrance Section Of Undersea Tunnel Based On UC-Win/Road

The entrance and exit sections of tunnels are accident-prone locations,and reasonable installation of traffic signs and markings can help reduce the occurrence of accidents.Variable speed limit signs,visual deceleration markings and other speed reduction facilities have been installed at some tunnel entrances,which have improved traffic safety to a certain extent,but the synergy between variable speed limit signs and visual deceleration markings has not been clearly defined in the relevant standards and specifications.As a special type of road tunnel,the safety of traffic in undersea tunnel is generally lower than that of ordinary road tunnels.Therefore,it is of great practical significance to study the synergy between variable speed limit signs and visual deceleration markings at the entrance section of undersea tunnel in order to effectively control vehicle speed and improve traffic safety.The main research elements are as follows.(1)The driving safety of the entrance section of the Cross Harbour Tunnel is analysed in terms of driver characteristics and driving environment characteristics;based on the theory of driver visual characteristics,the visual characteristics of drivers at the entrance section of the Cross Harbour Tunnel are analysed;based on the principle of the role of variable speed limit signs and visual deceleration markings,the front distance,height and lateral distance of the variable speed limit signs are determined in relation to the road conditions at the entrance section of the Cross Harbour Tunnel,in conjunction with existing research results.Based on the location of the variable speed limit signs and the length of the visual deceleration markings,the spacing of the variable speed limit signs and visual deceleration markings was determined.speed limit signs and visual deceleration markings.(2)Based on the designed 24 sign and marking synergy schemes and the actual engineering design documents of Qingdao Jiaozhou Bay Undersea Tunnel,a driving simulation scenario with variable speed limit signs and visual deceleration markings at the entrance section of the undersea tunnel was constructed using UC-win/Road and other modelling software.The driving simulation experiments were conducted by 24 drivers using Blue Tiger driving simulator,Tobii Pro Glasses 2 eye-tracking device,etc.The driving data such as driving speed,driving time,driving distance and deceleration speed,as well as eye movement data such as pupil diameter,gaze point distribution and number of gaze points of the driver were collected during the simulation.(3)The data analysis software was used to process the vehicle driving data and driver visual characteristics data obtained from the driving simulation experiments,and to analyse the changes of parameters such as speed reduction rate,deceleration rate,driver gaze ratio and pupil diameter under the synergistic scheme of variable speed limit signs and visual deceleration markings at the entrance section of the undersea tunnel.The evaluation index system of the effectiveness of the cooperative scheme of variable speed limit signs and visual deceleration markings at the entrance section of the undersea tunnel is determined,and an evaluation model of the effectiveness of the cooperative scheme of variable speed limit signs and visual deceleration markings at the entrance section of the undersea tunnel based on the entropy weighted elements is constructed.speed limit signs and visual deceleration markings at the entrance section of the Cross Harbour Tunnel.