Identifying Key Road Sections In Emergency Evacuation Road Networks And Optimizing Evacuation Strategies

In recent years,the frequency of various types of unexpected traffic incidents has increased significantly.These incidents have had a serious impact on the urban transportation system.After the occurrence of a sudden traffic accident,the traffic management department must adopt reasonable traffic organization measures or strategies for evacuation in a short period of time to reduce the hazards of the incident.However,due to the dense population of the city and the huge amount of car ownership,the current urban road network cannot meet the current normal traffic demand.If unexpected traffic incidents occur again,traffic demand will increase sharply,and the original traffic network will be damaged to varying degrees.This will cause great imbalance in the supply and demand of the traffic system.The original traffic organization could not effectively complete the evacuation mission.How to adopt an appropriate emergency evacuation organization strategy to reorganize emergency road network road sections,improve the existing network to accommodate evacuation vehicle traffic,effectively increase the number of events after the occurrence of the situation,and quickly evacuate traffic demand in a clear direction to reduce the evacuation time,Reduce the impact of the incident,so as to increase the evacuation efficiency of the road network and reduce the evacuation pressure of the road network.Due to the limited management resources and the complex urban road network,it is very difficult to take into account any road sections.Therefore,the key road sections of the emergency road network should be found to be managed or reversed in order to save time and manage resources.Evacuation of the normal operation,and even increase the evacuation efficiency is the manager's top priority.This paper analyzes the key road section identification technology for emergency road network,and combines traffic network characteristics,traffic demand characteristics,and traffic flow characteristics in the urban road network under emergencies,and analyzes the traffic organization methods for key road sections.The emergency evacuation organization under the emergency environment in the traffic network is studied.Firstly,on the basis of the analysis of the key road segment identification methods of emergency evacuation traffic network,the minimum cost flow theory is used to establish the key edge identification model based on the minimum cost flow,and the corresponding algorithm is designed based on theclassic minimum cost path algorithm.Based on the key road sections under different research angles,the relationship between emergency evacuation efficiency and road sections under the condition of minimum cost and maximum flow was studied.The key road section identification algorithm was used to apply the improved incremental allocation method to get access to road sections under traffic allocation.The trend of the total running time of the road network under the state of degraded capability,using MATLAB and Vissim simulation to solve it,analyze the impact of each road section on the entire road network,and find the impact on the network in the road network and the possibility of being destroyed For high-profile roads,select effective traffic organization plans for key road sections to improve evacuation efficiency and reduce congestion and delays.Finally,take the road traffic network in Lanzhou City as an example to analyze the case,and use two different algorithms to find the key road sections that are most conducive to the evacuation of the current road network,and compare and analyze the road sections found,confirming the method proposed in this paper.