Intersection Signal Control Research Based On Passive Bus Priority

As urban traffic problems become more and more significant,bus priority strategy gradually becomes a key way to solve these problems.Specific measures of bus priority include:bus lane priority,signal priority,station optimization,etc.Among many bus priority measures,signal control has an irreplaceable role.For single-point intersections and arterials,this study proposes corresponding bus priority signal control strategies respectively.Simulation experiments are also conducted using VISSIM simulation software to evaluate and analyze the proposed methods.The specific work is as follows:1.For single-point intersections,the intersection total passenger delay minimization model with passenger delay as the optimization objective and saturation and green letter ratio as constraints is discussed.And for this model may cause the non-priority phase vehicle stopping number of problems,the model is improved,the specific steps are: the first step to find the intersection passenger minimum delay,and then on the basis of this delay to a certain range of appropriate increase,so as to determine the set of schemes of bus priority signal timing,and then from the set of schemes to select the scheme that makes the non-priority phase stopping number of minimum.The particle swarm is used to solve the single-point signal timing model,and the solution ideas and steps are given.2.For arterial intersections,the transit priority and arterial coordination methods are combined.With the total passenger delay minimization as the control objective and the arterial green time and phase as the control variables,the arterial passenger delay minimization model is established and the steps of model solution are given.4.Examples are selected to simulate the single-point intersection and arterial signal timing models,and the validity of the model and algorithm is verified.In order to further verify the applicability of the model,experimental simulations are designed for single-point intersections and arterials respectively,and the simulation results are analyzed.The results of the empirical simulation show that the improved model achieves bus priority within an acceptable range of delay increase compared to the passenger delay minimum model,resulting in a 4.5% reduction in the average number of stops for non-priority phase vehicles.The arterial bus priority approach proposed in this paper reduced the average arterial bus delay by 47.9% and the average passenger delay by 11.6%.Experimental simulation results show that the improved optimization model can reduce the average number of stops in non-priority phases while achieving bus priority within an acceptable range of delay increase.Compared with the status quo,the improved optimization model has a better improvement rate of passenger delays when the proportion of bus traffic in priority phases is larger.The improved optimization model improves the average number of stops better at higher flows in non-priority phases compared to the passenger delay minimum model.The trunk passenger delay minimum model is able to provide improvement on trunk passenger delay when the proportion of bus traffic is large,and cannot achieve the effect of bus priority when the proportion of bus traffic is small or when the proportion of social traffic is large.