Research On Variable Speed Limit Control Strategy For Highway Tunnel Groups

With the continuous increase in the number of highways in China,the number of highway tunnel groups is also constantly increasing.The increase in the number of tunnels greatly facilitates people’s travel,improves travel efficiency,and saves travel costs.However,while providing convenience for people,many traffic accidents have also occurred,with several tunnel groups being the most severe.Among the many causes of traffic accidents,driving speed has the most significant impact on traffic accidents.This is mainly due to the mismatch between driving speed and the special road environment of the tunnel group.Therefore,in order to reduce traffic accidents caused by driving speed to a greater extent,it is particularly important to develop a reasonable variable speed limit optimization plan.This article takes highway tunnel groups as the research object and focuses on variable speed limit control strategies.Firstly,by analyzing the accident data of highway tunnel groups,it is concluded that driving speed is the main factor affecting traffic accidents in highway tunnel groups.Then,the research on variable speed limit control strategies for highway tunnel groups is mainly divided into two parts: the study of variable speed limit for highway tunnel groups based on cellular transmission models and the study of variable speed limit for highway tunnel groups based on robust optimization theory.In response to the research problem of variable speed limit for highway tunnel groups based on cellular transmission models,firstly,improved cellular transmission models were established for rainy,foggy,and snowy weather.Secondly,based on the research background,an optimization model for variable speed limit for highway tunnel groups was constructed,and an adaptive genetic algorithm was designed.Finally,a numerical example was solved through programming and analyzed;In response to the research problem of variable speed limit for highway tunnel groups based on robust optimization theory,a cell transmission model with interference factors and variable cell length was first designed,and robust variable speed limit control was proposed.Then,based on the research background,a variable speed limit control model for highway tunnel groups was constructed,and a genetic algorithm was designed.Finally,a numerical example was solved through programming and the results were analyzed.The research results indicate that for each subproblem,optimization schemes for variable speed limit control of different highway tunnel groups can be obtained through numerical examples.This indicates that the variable speed limit control strategy method for highway tunnel groups constructed in this paper is feasible,and the research results can provide basic theoretical support for the rational formulation of variable speed limit control for highway tunnel groups.Meanwhile,the results of both schemes indicate that variable speed limits can effectively improve the traffic capacity of tunnel group sections and improve the traffic safety effect of tunnel group sections.The variable speed limit control strategy proposed in this article for highway tunnel groups has improved the overall safety guarantee technology of highways in China,and has theoretical value and practical significance for improving the speed limit problem of highway tunnel group sections.