Research On The Signal Coordination Control By Giving Priority To The Bus Right

In recent years,with the accelerating urban expansion,the pressure on urban transport has increased.Due to the limited urban transport infrastructures and the unlimited traffic demand,the unbalance between traffic demand and supply is becoming serious.Furthermore,urban traffic continues to become congested and the “inconvenient driving and driving difficulties” in cities will be more tough.Therefore,in order to effectively alleviate urban traffic congestion and actively promote urban sustainable development,it is necessary to focus on strengthening the construction of public transport system and infrastructure.Thus,the development of public transport could be guaranteed in the process of urbanization.After the review of both domestic and foreign literature,this paper will explain the basic theories including the concept of road rights,bus priority,classification and control strategies before clarifying a basic fact that bus priority in road right is the fundamental starting point of transit priority control.Common vehicle information collection technologies and detector placement schemes are also introduced.The information collection scheme is determined through the comparison of the advantages and disadvantages of information collection technologies and the consideration of the actual conditions.After that,the basic concept of transit priority control,delays and related parameters of signal timing at single intersection are deeply analyzed.The road rights of vehicles are quantified and a transit priority control strategy in the same phase and multiphase is proposed.In addition,combined with the analysis of single intersections,the objective function and constraints of the mainline bus priority are determined.A signal timing optimization model targeting to minimize the weighted per capita delays is established from the perspective of road right.Because of the nature of the most value problem and the non-linear multivariate single objective within this model,the genetic algorithm is employed to solve the problem and the optimization result is obtained through MATLAB programming.Finally,the model erected in this paper is applied to three consecutive intersections on Zhuque Street in Xi'an.By analyzing the influence of the change of bus road right coefficient on per capita delay,the vehicle road right coefficient value of the selected case is determined,and then brought into Programming solve.The obtained results are brought into VISSIM simulation.By comparing and analyzing the data before and after optimization collected by the detector in the simulation,the rationality and effectiveness of the model designed in this paper are verified.This paper investigates the trunk signal optimization problem from the perspective of bus priority.The erected model has reference significance for solving the problem of urban traffic congestion.It is significant for the improvement the operation of public transport and the capacity of urban roads.Suggestions for the continuous improvement of urban road network system are proposed and these fulfill the theoretical framework of bus priority signal optimization study.