Research On Intelligent Control Method Of Tidal Lane

At present,"tidal traffic" has become a common phenomenon in large and mediumsized cities in China.The imbalance between the supply and demand of two-way traffic flow caused by tidal traffic leads to the mismatch between the supply and demand of spatial resources and the sharp decline in the operation efficiency of road traffic.The resulting road traffic congestion seriously restricts the operation efficiency of road network.Setting up tidal lanes is an effective measure to solve the problem of tidal traffic on urban roads.It is also an important subject for experts and scholars at home and abroad to study and solve the imbalance between supply and demand of traffic flow direction.Although tidal lanes were proposed as early as the 20 th century,China really began to use tidal lanes in 2003.Although the importance of tidal lane-setting has been recognized at present,there are few studies on the control strategy of tidal lane-setting.With the complexity and changeability of traffic situation,the simple control mode can no longer cope with the fragile and changeful traffic environment,resulting in the following two problems in the current control of tidal lanes:(1)due to the wide use of timing segment or manual command control,the utilization of tidal lanes cannot solve the problem of unbalanced supply and demand of the flow direction of the sections outside the tidal lanes,so it cannot adapt to the current complex and changeable traffic environment.(2)In the course of direction switching of tidal lanes,the setting of clearance time is unreasonable.For tidal lanes with long distances,the corresponding clearance time will be set for a long time.In the process of clearing tidal lanes,the lanes that have been gradually cleared will waste space resources.The main reasons for these two problems are analyzed:On the one hand,due to the lack of in-depth study on the management and control strategy of setting up tidal lanes,there is a lack of fine and intelligent management and control of tidal lanes.On the other hand,there is a lack of exploration on the variation law of traffic flow parameters such as speed and density in the course of direction switching of tidal lanes,and a lack of theoretical basis for fine management and control of tidal lanes.Based on the project of Shandong Key Research and Development Program,this paper focuses on the evolution of the speed and density of two-way traffic flow in the course of direction switching of tidal lanes.On the basis of theoretical analysis,the dynamic intelligent management strategy is put forward to realize the fine and intelligent management and control of tidal lanes.Based on the above research purposes,the paper analyzed the main reasons for the occurrence of tidal traffic phenomena,studied the distribution characteristics of tidal traffic flow in time and space,and put forward the requirements of setting tidal lanes.Then,the theoretical model of tidal traffic flow in the process of direction switching is studied.Since cell transmission model has a good simulation effect on unsaturated,saturated and oversaturated traffic flow,Therefore,based on the cell transmission model,this paper constructs a macroscopic traffic flow model with tidal lanes and reveals the state evolution rules before and after the opening of tidal lanes.The model is established to obtain the changing law of traffic flow velocity,density and other parameters in the process of tidal traffic lane's direction switching in real time,so as to provide theoretical basis for intelligent control strategy.Finally,aiming at the main problems of setting up tidal lanes at present,based on the theoretical model,the dynamic direction switching mode of the tidal lane is proposed,which the tidal lane is divided into segments and opened in segments.Taking the real-time traffic flow and congestion length as the decision variables of the tidal lane management and control,the dynamic control strategy of the tidal lane is put forward,which makes the control of the tidal Lane more suitable to the actual demand of the two-way road.The theoretical model and control method proposed in this paper have important reference and practical value for setting up tidal lanes on urban roads in China.