Research On Urban Intersection Signal Control Methods Based On Engineering Practice In Beijing

With China’s rapid economic development, urbanization gets fast in progress, car ownership increases rapidly, thus traffic problems like road congestion are getting more obvious each day. Particularly, in mega-cities represented by Beijing, traffic jams occur frequently, which not only significantly reduce people’s daily work efficiency, but also has seriously affected the normal operation of the city, resulting in losses impossible to estimate. It is work of great practical significance to look for a variety of effective ways to disperse vehicles on the roads and reduce congestions. For Beijing, city expressways, major roads and part of the secondary roads are seriously congested during peak hours, and the bottlenecks locate in the urban road intersections. The intersection traffic signal control is an important factor to affect the operating efficiency of urban road network and traffic control signal re-design is one of the important means to optimize intersection design, solve or alleviate the traffic congestion in Beijing.This thesis chooses recently optimized110intersections by the Beijing Traffic Management Bureau as the research objects. For the difficult problems encountered in the signal control design process of the110intersections, engineering-practice-oriented urban traffic signal control methods are studied, which involves three levels:timing control, inductive control and self-adaptive control. Based on the analysis of status and development of intersection signal control in Beijing, this thesis starts from the universally applied timing control in Beijing, and studies the city major roads coordinated control modeling method based on Synchro; then from the long-term perspective of intersection signal control in Beijing, this thesis studies inductive control modeling approach based on VAP; finally, focusing on the shortcomings of inductive control, the thesis induces intelligent algorithm to implement self-adaptive control, and studies fuzzy modeling method based on Matlab and VAP. Details are as follows:(1) City major road coordinated control modeling method is studied based on Synchro, and this thesis goes deeper in four aspects namely driveway utilization amendment, protective left-turn amendment in left-turn waiting area, permitted left-turn amendment and the minimum green time. Combined with actual traffic survey, the thesis proposes the point control and line control parameter correction method applicable for intersections in Beijing based on Synchro, and take Ronghua Road in Yizhuang New Area, Daxing District for example, to carry out an empirical study. As the result indicates, the optimization effect is obvious, and the parameter correction method compensate for the defects based on Synchro.(2) Urban intersection inductive signal control modeling method based on VAP is studied, and fundamental model problems of basic parameter settings and left-turn waiting area design in VAP are solved. The South Axis BRT Line of Beijing is taken as an example and intersection bus signal priority design and simulation of empirical research is carried out from three aspects namely full-inductive control, bus-inductive control, semi-inductive control. As the results show, timing control, full-inductive control, bus-inductive control, and semi-inductive control each has certain advantages and disadvantages and the method should be decided according to related transport policy.(3) The thesis studies the urban intersection fuzzy control design and simulation modeling method, designs four kinds of urban intersection fuzzy controller based on Matlab, studies the fuzzy control method based on neural network, attempts to induce fuzzy control to the modeling of VAP and proposes urban intersection fuzzy control design and simulation modeling method based on VAP, which is tested by empirical study. As the empirical evidence shows, the control effect and the cost is inversely proportional, that is to say, the neural network fuzzy optimal control method is the most effective, the two-level fuzzy control goes after it, followed by the inductive control and timing control is the worst in efficiency.In conclusion, starting from the perspective of engineering practice, the thesis aims to solve the difficult problems encountered in signal control optimization process of the chosen110intersections in Beijing, and studies the implementation of timing control method based on Synchro, which is in urgent need. From the long-term perspective of intersection signal control, the thesis carries out and exploratory study of intersection inductive signal control and fuzzy control modeling methods based on VAP, which solves the interaction of VAP with Matlab in urban interaction fuzzy control.