Research On The Mechanism Of Traffic Congestion Diffusion In Urban Road

In recent years,the rapid development of the social economy,the rapid progress of urbanization,the rapid increase of the citizens' motor vehicles.The traffic demand for urban roads has gradually exceeded the traffic supply.It is restricted by the economic conditions of the city,the land use,the transportation supply is difficult to improve,and more technology and means are needed to manage the traffic needs.And to improve the efficiency of road utilization,the study of traffic congestion diffusion mechanism is to analyze the time and space distribution changes after congestion,speed up the speed of congestion and dissipation,make full use of the existing road to ensure the smooth operation of urban traffic.The traffic guidance technology has brought new ideas to alleviate urban traffic congestion,but it is imperative to build a rapid and accurate traffic guidance system because of the difficulty of collecting real-time information,slow processing and lack of means of release.This paper first analyzes and summarizes the research on traffic congestion at home and abroad,summarizes the fundamental causes and hazards of traffic congestion,and the emerging intelligent traffic guidance system,and deeply analyzes and discusses the achievements of the research on the mechanism and control strategy of traffic congestion.First,the cellular transmission model proposed by the predecessors is adjusted,and the cellular transmission section model and the cell transmission node model are obtained,and the dynamic path selection model with real-time traffic information is constructed,and the suitable shortest path search algorithm is given,and the traveler is described through the minimum path impedance.The path impedance calculation method is given.The traffic congestion severity is judged by two indexes of traffic congestion scale and congestion delay,and their calculation methods are given.Experimental results show that the model constructed in this paper can effectively simulate the diffusion and dissipation of traffic congestion.Secondly,using C++ to simulate CTM,the influence of traffic information updating frequency on traffic congestion diffusion is studied.A road network model is proposed.The influence of road grade and road network level on traffic congestion diffusion is studied,and the diffusion process of traffic congestion is analyzed.The results show that the increase of real-time traffic information update frequency can effectively reduce traffic congestion delay and congestion diffusion,the road grade difference has a great influence on traffic congestion,road network gradation will affect the congestion scale and congestion delay of the road itself,but the congestion scale and support for traffic events will be affected.Blocking delay has little effect.By using the cellular transport model,the effect of event severity on traffic congestion diffusion is studied.By analyzing the duration of the event,the size of the loss of traffic capacity and the changes in the time and space distribution of traffic congestion,the conclusion is that the more serious the traffic incident is,the greater the diffusion range of traffic congestion is,the greater the traffic congestion is,the greater the traffic congestion is,the more the traffic congestion is spread.The greater the delay in congestion.In the end,according to the results of the previous article: improving the updating frequency of real-time information and reducing the severity of traffic events can effectively alleviate traffic congestion,the static control method and dynamic control strategy of traffic congestion are discussed.At the same time,a traffic guidance system is constructed to improve the frequency of real-time traffic information release,and the main frame of the traffic guidance system is set up.The traffic guidance system is introduced from three aspects of information collection,information processing and information release.