Research On The Evolution Law Of Occasional Traffic Congestion In Urban Areas Based On The CTM Model

At present,the social economy is developing rapidly,and the level of urbanization is increasing.As a result,the problem of urban traffic congestion has become more serious.Occasional traffic congestion has a serious impact on urban traffic safety and operational efficiency due to the uncertainty of its occurrence.It has brought a series of hazards such as economic loss,environmental pollution,and waste of resources.How to alleviate the occasional traffic congestion has become one of the urgent problems to be solved in the development of urban transportation.Based on the characteristics of urban traffic congestion,this paper takes sporadic traffic congestion as the main body of study,and builds an urban network model based on the actual characteristics of the transportation network to simulate the evolution of traffic flow under different supply and demand structures.Then this paper studies the spatiotemporal characteristics and diffusion mechanism of sporadic traffic congestion,and proposes an effective traffic control strategy.This paper mainly conducts research from the following three aspects.(1)For the urban road network,considering the problems of traffic flow hysteresis and signal control,the cell transmission model is improved.This paper proposes a path search algorithm based on intersection latency,and establishes a dynamic path selection model based on real-time road impedance.On this basis,establish a transmission model with real-time traffic information update and dynamic route selection functions and make the transmission process of road sections and nodes more in line with actual traffic conditions.A unique congestion evaluation index is established for the cell transmission model.(2)Discuss the influencing factors of occasional traffic congestion,and use Matlab software to program the transmission model.Simulate the traffic flow operation situation in Xi'an road network when sudden traffic incident occurs.The formation and evolution of incidental traffic congestion are studied in terms of the severity of the event,the location of the event,the duration of the event,the length of the canalized area,and the frequency of traffic guidance information update.(3)Based on the research results,reasonable and effective traffic congestion control strategies are formulated from three aspects: intersection signal control,congestion area control measures,and traffic guidance system.This paper proposes a reasonable and feasible model and research method for the evolution of urban sporadic traffic congestion.It also explores and analyzes the influence of signalized intersection control on model transmission,improves the accuracy of the transmission model,and provides a modeling method for the application of cellular transmission models to traffic flow simulation.It also verifies the applicability and practicability of the cell transmission model to simulate traffic flow under different road network conditions.It can provide references for urban traffic management and road network design,and provide new ideas for traffic management departments to alleviate urban traffic congestion.