Study On Spatial Impact And Capacity Of Freeway Traffic Accidents

With the continuous progress of social economy and the continuous increase of vehicle ownership,the rapid increase in transportation demand has led to an increasingly serious traffic problem in China.The main manifestations are chaotic traffic and road traffic accidents,resulting in traffic congestion and delays.The road network's operating efficiency has been reduced,and it has even resulted in casualties and property losses,which have adversely affected the society and economy.Rationally determine the scope of the accident after the occurrence of the accident,and propose traffic capacity analysis methods for different impact areas.Based on this,formulate a reasonable traffic organization plan to ease the chaotic traffic flow at the accident site,increase rescue efficiency,and ensure the smooth running of the vehicle.Therefore,after the accident,it is very important to quickly determine the space impact of the accident and the remaining traffic capacity on the safe traffic management of the expressway.Based on the existing research results at home and abroad,this paper attempts to analyze the spatial impact of freeway traffic accidents and the traffic capacity of each affected area,so as to take reasonable traffic organization measures in the accident area and quickly eliminate the impact of traffic accidents.Firstly,analyze the main features of highway traffic accidents,understand the impact of traffic accidents on freeway traffic flow and its operating conditions,and dig the influencing factors of traffic capacity under highway accident conditions to lay the foundation for followup research.Secondly,based on the traffic flow basic model and the traffic wave theory,the traffic wave equation under the Van Aerde model is constructed,and the influence of the traffic waves on the upstream section of the incident position is analyzed,and then the traffic accident influence propagation analysis method under the road environment is extended to the road network environment considering the remittance and remittance flow.Finally,according to the impact of traffic accidents,the impact area of traffic accidents are defined as protected areas,control areas and buffer zones,providing a theoretical basis for the analysis of the capacity of the subsequent impact area.Thirdly,the traffic capacity of each affected area of the traffic accident is analyzed,and the traffic capacity of the expressway accident site area under the traffic accident is analyzed by combining the simulation analysis and the correction coefficient.By analyzing the vehicle lane changing behavior in the transition region,the traffic capacity analysis method is proposed.A traffic capacity analysis method based on headway distribution is proposed.The capacity analysis of buffer zone refers to the capacity analysis under normal circumstances.Finally,combining with the actual case of a highway,the VISSIM simulation software is used to simulate the traffic flow status of the accident site,evaluate the effectiveness of the queuing model,and verify the rationality of the traffic capacity analysis model under accident conditions.