Traffic Characteristic Analysis And Connected Control Strategy Of Urban Expressway Merging Area

The urban expressway has high efficiency and wide coverage.Nowadays,it has become an important part of urban traffic.In the urban expressway,the merging area is the key node to bear the connection between the expressway and other roads,and it also affects the urban expressway.The merging area also is the main bottleneck of traffic efficiency.In this paper,the vehicle running characteristics and efficiency improvement of the expressway merged section are taken as research targets,and the following research work is carried out:(1)Field investigation and analysis of traffic flow data in the merging area.During the investigation,we used aerial photography equipment to collect data on the traffic flow of a typical expressway merging area in Xi’an,and conducted on-site investigations on the confluence area.Subsequently,we processed the video survey data and obtained data on the driving and lane change behavior of more than a thousand vehicles in the merging area.(2)Analysis of lane changing characteristics and traffic flow disturbance in the merged area.We used traffic flow survey data to analyze the trajectory of more than 300 lane-changing vehicles.Through analysis,we believe that there are two main types of lane changing behaviors in the merging area,one is the lane change behavior of the inflow into the vehicle,and the other is the lane changing behavior caused by the instability of the main road traffic due to the merging process.We analyzed the impact of the second type of lane change behavior,and considered that the vehicle delay caused by the lane change is not only related to the target lane clearance,but also related to the speed difference between the lane change vehicle and the target lane.(3)Study on the optimization strategy of traffic flow in the merging area of the pre-change method.Through in-depth analysis and summarization of the lane changing behavior and its impact,we have established a convergence strategy in the network environment.The optimization strategy aims to make the outside lane vehicles more reasonable.The behavior of the road,thereby reducing the lane changing behavior of the main road vehicles in the merging,thereby reducing the delay caused by the overall traffic flow in the merging area and improving the overall traffic efficiency.(4)Pre-change strategy simulation verification.We use VISSIM’s secondary development interface to establish a simulation platform for the vehicle networking strategy with Visual Basic and MATLAB,and perform 20 simulation experiments on the common traffic flow and strategy implementation.At the same time,we analyze the simulation data and find that the optimization strategy designed in this paper has a certain improvement on the overall delay of the confluence area,and verifies the effectiveness of the pre-change strategy.Through the above four aspects of research,this paper believes that the main factors affecting the passage of the merging area are not only the merging process,but also the lane change behavior of the main road traffic caused by the merging process.At the same time,it is found that the second type of lane change behavior has a major impact on the traffic flow.The track speed difference is related to the lane change gap.Therefore,this paper designs a control strategy to reduce the influence of the main lane change behavior,and reduces the overall delay of the traffic flow by selecting a reasonable lane change vehicle to change lanes in advance.Then the simulation of the strategy of this paper is carried out.The simulation results show that under the condition of uniform traffic flow,this strategy can reduce the traffic delay in the merging area and improve the traffic efficiency.