The Establishment Of Traffic Diversion Model And Its Applied Research During Urban Road Transformation Period

With the increase of the auto possession, traffic demand also constantlyincreasing.At the same time, Road will also be changed . Road traffic congestioncaused by the reform became a regional development ill and bottleneck. During theroad diversion period, the road traffic management department tends to divert the roadthrough enforcement or ask the drivers themselves to opt for other road sections.Consequently, it cannot neither smooth the traffic network nor make the full use ofroad network. Therefore, the research on rational allocation of vehicle flow, theadjustment of space-time distribution of vehicle flow, and efficient planning of roadnetwork is of great significance. And it has also become public concern and a hot topicfor road traffic management department to study.Based on the above-mentioned background and the key project named RoadTraffic Emergency Management Research of Public Security Department of Hunanprovince, this paper carries out the research. Firstly, the paper uses the Unary LinearRegression Method (ULR), combined with the detailed data of traffic market research,to optimize the federal road impedance function (BPR function) in the U.S.A. Theoptimized results show that optimized BPR function bears good degree of fitting fordata, which lays foundation for the model-building of traffic diversion. Secondly, thearticle analyzes the characteristics of traffic operation during road diversion period. Bymaking use of the optimized BPR function, combined with the Wardrop userequilibrium theory, the paper establishes the calculation model of the total number oftraffic diversion during road improvement, and gives specific iterative algorithm. Afterthat, it builds the model of traffic diversion based on the objective function of theshortest time and writes the simulation program of the whole diversion model throughthe usage of the Matlab algorithm of the model simulation study, including thealgorithm simulation of a feasible path, algorithm simulation of the initial trafficdiversion, the improved algorithm simulation of the number of the initial diversion,and also a theory of the shunt-effective evaluation method. Finally, the paper put theestablished model of traffic diversion into application by taking the actual example ofroad improvement during the period of metro building in Changsha city in 2010. The results indicate that the diverted vehicle can reach optimal running time, and thesection after the shunt does not exceed the capacity of the road, which proves that themodel of traffic diversion has certain validity in practices.