Research On Priority Coordination Control Of Transit Signals At Intersections With Multiple Bus Request Conflicts

With the social progress and rapid economic development,the number of motor vehicles has grown significantly.The problem of congestion at road intersections in the morning and evening peak periods has become a problem that should be solved quickly by many cities.At present,the development of bus priority has become an important way for many cities at home and abroad to solve the problem of congestion at road intersections.Based on the research of scholars at home and abroad,this thesis,combined with actual investigation,has completed the analysis of the applicability of bus priority strategies.According to the actual situation,the comprehensive application of bus priority control strategy was studied,and the bus priority model for multiple bus request conflicts at the intersection was improved.JAVA language was used to program existing and improved models to compare the effects before and after improvement.Taking the intersection of Daliushu Road and Xueyuan South Road as an example,this thesis used VISSIM software to apply the improved bus priority model to conduct microscopic simulation of the intersection and verify the effectiveness of the improved model.The main work is summarized as follows:(1)Improve the bus priority control strategy,establish a delayed average vehicle model under green light time redistribution,construct a green light time redistribution decision-making process,and establish a comprehensive application of multiple strategies and bus priority control process combined with the green time extension strategy and red light time Early break strategy and green light time redistribution strategy.Use VISSIM micro-simulation software to simulate and verify the "comprehensive application process",and compare the average delay of buses and non-priority vehicles before and after,to verify the effectiveness of the "comprehensive application process".(2)The traditional bus priority model for intersection with multiple bus requests conflicts is improved.Analyzing the traditional bus priority model,the minimization of passenger delay is the deficiency of optimizing the objective function.In the objective function of the model,the weight factor of the number of buses and the offset of buses and timetables is increased.(3)A comparative analysis of before and after improvement of example of public traffic priority model for intersection with multiple bus request conflicts.By applying the JAVA language,based on particle swarm optimization(PSO)algorithm,the improved bus priority model for intersection with multiple bus requests conflicts in the fourth chapter is worked out.Based on the intersection of Daliushu Road and Xueyuan South Road,selecting the appropriate model parameters,bus priority model of intersection before and after improvement with multiple bus requests conflict is solved,and optimization model of bus priority traffic signal timing before(C-TSP)and after(A-TSP)improvement is compared and analyzed.From the analysis results,we can see that under whatever conditions,A-TSP is better than C-TSP.For the bus priority request conflict from the opposite direction,A-TSP shows a greater advantage.Not only did bus delays decrease,but also per capita delays were smaller,the validity of the model is verified.(4)Analysis of bus priority simulation model for intersection with multiple bus request conflicts.Through the application of VISSIM software,compiling the simulation program with the Visual Basic language,bus priority analysis of intersection with multiple bus requests conflict based on microscopic simulation(VISSIM)has been carried out.Bus priority request conflict from opposite directions,vertical directions and three directions has been simulated microscopically.In the case of above three kinds of bus request conflicts,the simulation results show that the effect of A-TSP is better.