Impact Analysis Of Public Stops Layout On Capacity Of Exit And Entrance Of Urban Expressway

ABSTRACT:Because of its heavy volume and fast speed.,the urban expressway is a mainstay in the traffic operation.It plays more and more important role in improving the service level and mitigate the press of the city transportation. But, as the number of personal vehicle increases sharply, the problem of traffic congestion occurs in the urban expressway has become more and more outstanding, especially in the peak hours, the access point of urban expressway is the bottleneck of the traffic capacity. When the layout of the bus stop unreasonable, it can make the bottleneck impact more seriously, meanwhile, it can also cause the relative roads and networks around into traffic jams,and at last cause traffic networks inefficient.This paper focus on the traffic capacity of the urban expressway access points infulenced by the the unreasonable setting of Bus Stop,which near the exit and the entrance urban expressway.Firstly, it systematically analyzes the characteristics and the problem of the Bus Stop which set on the urban expressway.Then describe the disturb process to the countious traffic flow which caused by the bus operating and parking on the urban expressway,combining with the vehicle's merge and diverget characteristics nearby the access point. Thirdly,based on the Gap Acceptance Capactiy Model for the off-ramp of Urban Expressway,establish the Capactiy Model for the off-ramp influenced by the setting of the bus stop.Meanwhile, analyze the reasons of the VISSIM why it suitable for solving this problem. In the end, take the bus stop setting on the upstream for example,making the simulation trial for fifteen times in order to research the capacity infulence of exit and entrance of the urban expressway which caused by the setting of the bus stop,by means of changing two main factors,one is the distance between the bus stop and the access point,the other is the bus reach rate.It also according to the investigation data of traffic characteristics about the south of the third-ring expressway in Beijing, referring to the exit of LiuJiaYao Bridge. Establishe the models based on traffic simulation. Selected the number of passing vehicles, the traffic travel time, the delay time, the length of the queue as the evaluation indexes. Throughing analyse the data of the simulation trials to summarize the law of the infulence,and draw a conclusion.of setting the bus stop nearby the exit and entrance of the urban expressway, on the premise of the distance between 30m-100m.so that can give a reference for the further research.As the limitation of time and manpower,the research can't refer to all side,so it needs to be come on in the future.