Research On Signal Timing Coordination Method Of Arterial Intersections Based On Bus Priority And Environmental Factors

Nowadays,many cities have already developed the Bus Priority as one of the important means to improve the traffic problems.At the same time,protecting the environment and green development have long been the concept that China must adhere to in the development process.Based on this,this paper takes the intersection as the research object,integrates the Bus Priority and Green Traffic idea into the single-point intersection signal timing optimization method and the arterial signal coordination optimization method,and respectively establishes the signal timing optimization model for calculating the effective green time of each phase and the arterial optimization model for calculating the arterial phase difference,and verifies the validity of the models through the actual intersection case.The specific work content is as follows:First,a single-point signal timing optimization model is established.In the study of single-point intersection,this paper takes the effective green time of each phase as the independent variable and selects per capita delay,per capita emissions and stops as the optimization indicators to establish the multi-target signal time optimization model considering bus priority and environmental factors.The model innovatively uses the fuzzy compromise method to transform each optimization index into a single objective function with values between(0,1),uses fuzzy preference method to determine the membership function weights and transforms the multi-objective model into a single objective model that is easy to solve.Finally,taking the intersection of Ping'an Lixi Street and Zhaodengyu Road in Beijing as the actual case,the paper verifies the optimization effect of the model by compareing the indexes before and after optimization which is solved based on Matlab software platform.Secondly,the traditional Particle Swarm Optimization algorithm is optimized.In order to optimize the search distance and tracking effect,this paper combines the two methods of adaptive inertia weight and asynchronous learning factor to propose an optimized particle swarm optimization algorithm to provide support for the accurate solution of the model.Thirdly,the arterial phase difference optimization model is established.In the study of the arterial phase difference model,this paper analyzes the four arrival forms of the arterial team to the downstream intersection,that is,the "head and tail are blocked ","head is blocked and tail is unblocked ","head is unblocked and tail is blocked " and"head and tail are unblocked ".Based on these four arrival forms,the seven value intervals of the bidirectional phase difference on the main line are analyzed.According to the calculation relationship of the bidirectional phase difference,the arterial phase difference optimization model is established whose independent variable is the up-direction phase difference and optimization indexes are the bidirectional per capita delay and the circle stops.Finally,the arterial optimization model is validated by the simulation.In this paper,four adjacent signal-controlled intersections in Miyun County are selected as example intersections.The traffic data is obtained through field investigation.The data is processed and brought into the single-point signal timing optimization model,the arterial phase difference optimization model and the traditional phase difference calculation method to calculate the optimized green signal ratio,system circle and phase difference.Then,using Vissim simulation software,the simulation platform of the instance intersection is built,and the effectiveness of the proposed model is verified by the simulation output.