Research On Speed Limit Control Strategy Of Highway Tunnel

As the driving environment of highway tunnel section is more complicated than that of ordinary section,the tunnel section becomes the highway accident-prone section.In order to ensure the safe operation of highway tunnels and improve their traffic efficiency,it is necessary to formulate reasonable speed control strategies for tunnels under normal weather,bad weather and traffic accidents.In this paper,the reason of tunnel speed limit is analyzed firstly,then the influence of different factors on the speed limit is analyzed from four aspects of driver,vehicle,road and environment respectively,and the speed model and corresponding speed limit value under various influence factors are established at the same time.Secondly,relying on the engineering example,the speed limit methods adopted in Dabashan tunnel are compared and selected.Taking into account the basis of tunnel section division,the tunnel section division and the preliminary calculation of section length are carried out.Then,a multi-factor speed limit model is established,and corresponding variable speed limit control strategies are formulated for different weather conditions.Then,the length of speed limit zone is revised from the angle of safety of speed limit zone.Finally,the PTV-Vissim simulation software is used to simulate the speed limit of traffic accidents in different sections,and the optimal speed limit control strategies for single-point accidents in section?,? and ? are obtained.The results show that under normal weather conditions,the speed limit strategy is different between day and night.Rainy and foggy days mainly affect the speed limit value at the entrance of the cave,and the corresponding speed limit control strategy can be formulated through rainfall intensity and visibility respectively.The speed limit control strategies for single-point accidents in section ?,section ? and section ? are also different.When single-point accidents occur in section ? and section ?,the speed limit control strategies can be considered uniformly.The speed limit control strategy adopted in this paper can be used for reference to improve the traffic efficiency and safety of tunnels under different weather and single-point accidents in different sections.