Traffic Boundary Control Strategy Based on Macroscopic Fundamental Diagram Under Different Rainfall

Adverse weather such as rain and snow often aggravates urban traffic congestion, and large cities such as Beijing and Tianjin often experience multi section regional traffic congestion under rainfall conditions. Therefore, based on the real traffic data of the road network in the central and suburban area of Tianjin, with the macroscopic fundamental diagram model as the research foundation, the paper compared the time series and the macroscopic fundamental diagram changes of road network traffic flow for different rainfall and road networks. It analyzed the impact of different rainfall on the traffic status of the road network in the central and suburban area of Tianjin. The dynamic evolution models of the road network were constructed based on the change law in macroscopic traffic flow of the road network in the central and suburban area under different rainfall, and their parameters were also calibrated and validated. Aiming at solving the regional congestion problem of the road network, the control strategies of the road network in the central area and the suburban area under different rainfall conditions were designed based on the perimeter control of macroscopic fundamental diagram. The effectiveness of different control strategies was verified through simulation experiments, and feasible strategies were proposed to alleviate road network congestion in central and suburban areas. The simulation results show that: under light rain conditions, the traffic status between the central area and the suburban area is more balanced and the road network regulation effect is better when the transfer proportion of traffic flow from the suburban area to the central area is reduced within the range of 9% to 50%; under the condition of heavy rain, the traffic status of the central area and the suburban area is more balanced and the road network regulation effect is better when the reduction is controlled within the range of 23% to 50%. This shows that the control strategy can alleviate the traffic congestion of the road network and ensure the stable operation of the road network traffic system.