Study On The Influence And Evacuation Strategy Of Highway Tunnel Traffic Accident

As a special section of highway,the tunnel is liable to cause serious congestion and even lead to the occurrence of accident for the second time because of the particularity of the environment.Often due to the lack of effective emergency evacuation strategy planning,it could cause a wide range of congestion,and even affect the surrounding road network.To formulate and implement effective evacuation strategy is an effective measure to reduce the impact of tunnel accidents,alleviate congestion and improve traffic safety.This paper first analyzes the traffic flow characteristics in the tunnel before and after the accident,and then studies the collected tunnel accident data by means of statistical as well as chart analysis.The distribution characteristics of time,space and vehicle type of highway tunnel traffic accident are obtained,at the same time,the degree concerning the influence of different factors on the accident is analyzed from the aspects of person,vehicle,road and environment;concerning the characteristics and influencing factors of tunnel accident,the paper analyzes the duration of the accident by using regression analysis and decision tree model,and the traffic wave model is used to predict the length of the jam caused by the accident,which provides the basis for the formulation of evacuation strategy for the tunnel accident.Secondly,combining with the engineering example,the traffic evacuation strategy in the accident tunnel is put forward according to the accidents of different degree in different sections of the tunnel.In the case of tunnel fire accident vehicle evacuation,combining with the speed of smoke diffusion and evacuation speed,the evacuation strategy of the stranded people in the tunnel under fire is given.Finally,with the help of PTV Vissim simulation software,the tunnel operation state is simulated under different traffic conditions,and the improvement degree of tunnel accident impact is compared by using different evacuation strategies under different traffic conditions,in order to find out the optimal evacuation plan under different accidents,at the same time,the evacuation process of tunnel stranded people under fire accident is simulated,obtaining the minimum evacuation time to verify the feasibility of safe evacuation.The results show that the traffic volume and the duration of the accident are the important factors affecting the severity of the accident in the tunnel,and the severity of the accident also affects the formulation of the evacuation strategy.The evacuation efficiency of the evacuation strategy is different under different traffic volume.In practice,the evacuation strategy should be reasonably selected in terms of evacuation efficiency,traffic safety,ease of implementation and so on.The research results of this paper have positive significance to improve the tunnel emergency management system and the efficiency of accident treatment.