Research On Traffic Signal Control Method Of Roundabout Considering Emissions

Roundabout is a special form of intersections in my country’s urban road network.In the early development of urban roads in my country,such intersections were widespread and played an active role.However,with the growth of traffic volume,the shortcomings of its insufficient capacity have begun to appear,and more and more roundabouts have become the traffic bottleneck of the urban transportation network.The congestion of vehicles at the intersection causes a large amount of exhaust pollution in the intersection area,which leads to the deteriorating urban traffic environment.Setting up signal control at roundabouts is an effective way to solve the problems of traffic congestion and serious pollution at intersections.For this purpose,this paper has carried out a systematic study on the traffic signal control of roundabouts considering emissions.First,the paper introduces the development and research status of roundabouts at home and abroad,summarizes three common ways of signal control at roundabouts,and analyzes the applicable conditions and existing problems of the three signal control methods.On this basis,the signal timing of roundabouts is analyzed emphatically.Secondly,combining VISSIM simulation software and VSP model to build an exhaust simulation calculation platform.Through this platform,the capacity and emission distribution of a typical roundabout under different traffic conditions are studied.Starting from energy saving and emission reduction,it provides a reference for the selection of roundabout control methods.Thirdly,taking into account vehicle operation efficiency and environmental benefits,the multi-objective model optimization method is studied,and the multi-objective optimization signal timing model of the three control modes of the roundabout is established,and the model is solved by the NSGA-II multi-objective optimization algorithm.The TOPSIS method based on entropy weight is used to obtain the optimal solution from the optimal solution set.Finally,select a roundabout for a case study to investigate the geometric information of the intersection,the traffic flow at different times,and the signal timing of the intersection.Considering the current situation,the control plan is not well set,and the signal control method and signal are considered from two aspects of timing method,four signal control optimization schemes are designed.Based on the current control method and timing scheme,the optimization effects of different optimization schemes are compared.The results show that the roundabout signal optimization model with emission considerations constructed in this paper can not only effectively improve the traffic capacity of the roundabout and reduce the vehicle delay at the roundabout,but also reduce the exhaust emissions of the vehicle roundabout to a certain extent.