The Speed Limit Determination of Tunnel Entrance And Exit Section On Rainy Days

Abstract

In order to reduce the number of traffic accidents caused by rainy days on the entrance and exit sections of tunnels, a reasonable speed limit value on the entrance and exit sections of tunnels is proposed to improve the safety of vehicles on these sections. This paper takes passenger cars as the research object, and by exploring the changes of road friction coefficient and visibility in rainy weather, the driving environment parameters under different rainfall intensity are clarified. Taking the visible distance of the driver and the critical state of vehicle sideslip as safety indexes, the speed limit value of the section outside the tunnel in rainy days is obtained, and the allowable speed of the section inside the tunnel is determined by taking the continuity of the running speed as the standard. The study shows that the speed limit value of the tunnel entrance and exit section in rainy days takes visibility as the main limit index and decreases with the increase of rainfall intensity. When the rainfall intensity is greater than 1.5mm/min, the speed limit of the tunnel section is needed.