Study On The Strategies Of Traffic Organization And Signal Control For Urban Intersections

The development of transportation is tie up with the development of the whole city. With the fast development of economy, urban traffic volume increases quickly, traffic congestion appears frequently and the pressure of urban traffic becomes more and more heavy. The transportation problems are always the difficulty that disturbing people of all transportation fields. In the urban road network, routes are connected with each other by intersection . Urban intersections becomes the key nodes of urban traffic, and as urban traffic congestion usually happens in the intersections, the urban intersections have been a series of bottlenecks. All of above make the traffic congestion concentrated on focus of traffic flow conflicts and intersection capacity and it in fact requires for studying on making best use of space and time resources of the urban intersection. Just based on the point, this thesis studies on the strategies of traffic organization and signal control for urban intersections. In order to solve the problems of urban traffic congestion, this thesis puts forward a series of measures such as traffic channellization design ,signal control, urban traffic flow guidance and so on. And it particularly studies on design of the multi-phased and signal control with optimized combination of traffic channellization and signal control, furthermore it also profoundly discusses intersection dispersal strategies coordinated with traffic flow guidance under traffic congestion, At last this thesis researchs into the organization and signal control strategies of transit priority at intersections. The more details are as follows: Chapter one first introduces background of this thesis, and then analyzes the influence of intersection for traffic congestion, and points out countermeasures of urban traffic local congestion. Based on introduction of current overseas and domestic research on strategies of traffic organization and signal control for urban intersection, significance and purpose of this thesis are illuminated in detail. And then the main content and research methods are provided with at last. Chapter two mainly analyzes the traffic characteristics of urban intersection. The characteristic points at the urban intersection are introduced in detail. Based on the study of the characteristics of the signalized intersection, utilization and loss of signal green time are thorough analyzed. And then this thesis discusses calculation method and influence factors of saturation flow rate, in following gets the signalized intersection capacity. At last this thesis also studies on calculation method of the signal control schemes of the urban intersection. Chapter three mainly studies on methods and theories of traffic channellization design for urban signalized intersections .The main content consists of channellization definition, function, principle, measures, application, multi-phased channellization and control, flow course of traffic channellization and so on. And then optimized combination of signal control and traffic channellization is discussed, in following multi-phased channellization of urban signalized intersection is particularly studied. Lastly with optimized combination of signal control and traffic channellization, the projects of multi-phased channellization are designed, Furthermore choosing the optimization projects is finished with the traffic simulation software VISSIM. And the results of traffic simulation show that the pressure of traffic congestion can effectively lightened. Chapter four mainly studies on the dispersal control strategies for urban traffic intersection congestion. Based on the analysis of traffic congestion mechanisms and oversaturated traffic flow characteristic, the thesis points out the causes of traffic congestion . And then the strategies of traffic flow guidance is introduced in order to solve the traffic congestion, According to above analysis, this chapter lays emphasis on the research of dispersal and control strategies. In order to solve the problems of traffic congestion at urban intersection, the dispersal strategies is put forward in time. In order to get the dispersal schemes carried out effectively, the strategy of green wave control for the lower reaches intersections is simultaneously applied. And this chapter particularly discusses prediction of queue length and the definition of crowding degree at the intersection and also studies on the course of carrying out dispersal control strategies and the offline generation of dispersal...