The Research Of The Urban Expressway Capacity And Improvement Measures After Traffic Accidents

With the rapid development of urban economy and the acceleration of the urbanizationprocess in china, the supply pressure of city road network is increasing, and traffic safetyissues also have become increasingly prominent. As an important part of the urban roadinfrastructure, urban expressway, which has the characteristic of fast speed, high trafficservices volume and capacity, bears the traffic demand function between city internal areas.However, sudden traffic accidents on the expressway system, which dropped the roadcapacity significantly, increased traffic delays and travel time, even caused a number ofcasualties and property losses, will have a great impact on the operating environment andtraffic safety of the regional road network. In order to alleviate traffic congestion caused bythe accident, improve the rescue efficiency and the efficiency of traffic accidentsorganizations after traffic accident and protect safe and orderly operation of the regional roadnetwork, quantitative analysis and research of the urban expressway capacity andimprovement measures after traffic accident will have important significance.Therefore, according to the road accident statistics in china, the paper summarizes andgeneralizes the characteristics of city road traffic accidents at first. And in accordance withthe change of the driving behavior and road operating environment after traffic accident toanalyze the characteristics of urban expressway and traffic characteristics. Meanwhile, takinginto account the stage of the traffic accident, in combination with crowded durationcomposition analysis, study urban expressway evolution characteristics and traffic congestionformation process to provide theoretical support for the follow-up model building.Secondly, through the influence factors analysis of the urban expressway capacity aftertraffic accidents, and according to the formula of the capacity under normal conditions, thepaper proposes the calculation model of city expressway capacity after traffic accidents. Themodel combines with the method of simulation analysis and correction factors analysis. Atthe same time, based on cellular automata to construct traffic flow model and set uplane-changing rules, using MATLAB programming software as a simulation platform tosimulate for the correction coefficient of each influence factor, further achieve quantitativecalculation of the urban expressway capacity after traffic accidents, which provide data support for timely and effective control strategies were taken by urban traffic managementdepartments.Finally, according to the calculation results of the urban expressway capacity after trafficaccidents, the paper puts forward to traffic improvement measures which include trafficcontrol, induction and speed limitation, and use MATLAB programming software to analyzeand compare the effect of these improvement measures.