Research On Coordinated Control Methods Of Arterial Road Under Oversaturated Conditions In The Critical Intersection With Bidirectional Green Waves

With the continuous increase of vehicle ownership worldwide,more and more traffic congestion and oversaturation occur in urban roads.In order to solve the problem of traffic oversaturation,it is necessary to make coordination and adjustment between time and space.When it is difficult to channelize the physical space of roads and intersections,the time adjustment of traffic signal control becomes more important.Different from the over-saturation phenomenon at a single intersection or the whole artery,there are certain studies on the phenomenon.When a node(intersection)in a arterial line with bidirectional green waves is over-saturated,whether and how much influence it has on the whole green wave arterial line and the green wave control,how to optimize the control method needs to be further discussed.Therefore,it is of practical significance to study the strategies and methods of arterial line coordination control under the condition of oversaturation at critical intersections of bidirectional green waves.Firstly,this paper qualitatively describes the oversaturated state from the time dimension and space dimension,and according to the waste of green time in the oversaturated state,puts forward the quantitative method of the supersaturated state coefficient in time dimension and the oversaturated state coefficient in space dimension.Then,the key of the main thesis of bidirectional green waves intersection and the primary and secondary direction has carried on the qualitative description,and through the uneven coefficient of saturation and direction for the quantitative expression,further put forward the critical intersection bidirectional green waves two scenarios--the main direction of the oversaturated state coordinate phase occurs,both parties to coordinate oversaturated phase.Furthermore,thesis of bidirectional green waves of two critical intersection oversaturated scenario put forward the corresponding control strategy,the supersaturated state coefficient,according to the time/space dimension from the queue and eliminate surplus overflow,by adjusting the parameters in the signal timing(Cycle,Split,Offset,etc.),is proposed based on maximum flow model of oversaturated state arterial coordination control method were proposed to improve the place of FBP(ForwardBackward Procedure)method to solve the model.In addition,the paper uses the maximum number of passing vehicles(V),the minimum average delay time(D)and the minimum average stopping times(S)as evaluation indexes,and proposes an evaluation model of arterial line coordination control under the condition of oversaturation.Finally,in the case study of S.Virginia.St in Reno,Nevada,USA,TransyncD,the green wave optimization software and VISSIM,micro-simulation software were used for simulation.Based on the analysis of simulation data,the proposed control method was verified to be effective.Through research,this paper provides a certain basis for optimizing the arterial line coordination control method under the condition of over-saturation at critical intersections with bidirectional green waves,and provides a certain theoretical basis for the arterial line coordination control strategy and method under the condition of oversaturation in specific scenes.However,there are so many oversaturated state scenarios that need more control methods to be applied,which is worth further discussion in future research.