Optimal control method of dynamic speed limit at tunnel entrance section based on multi-objective constraints

Due to the particularity of the operating environment of expressway tunnels, it is difficult to rescue and evacuate personnel when emergencies occur in tunnels, which seriously affects the safety and efficiency of tunnels and related expressways. In order to ensure the safe operation of the tunnel and explore the hidden dangers of tunnel traffic operation, a traffic flow model is used to determine the variable speed limit value with the minimum delay time as the goal and speed, density, acceleration, weather environment, and human visual factors as constraints, and use simulation software to compare the emergencies in the tunnel, reduce the discreteness of vehicle speed when no emergencies occur, reduce the delay time of vehicles in the tunnel when emergencies occur, and control the stability of vehicle speed. It shows that the construction of an intelligent control strategy for vehicle speed dynamic guidance for the safety and operation efficiency of popular vehicles in tunnel traffic can effectively improve the operation efficiency of traffic and ensure the safety of traffic in the tunnel.