Research On Collaborative RAMP Metering Meethod Based On Traffic Accident Of Freeway

In recent years, with the rapid development of social economy, the traffic volume of the highway has also increased rapidly, and the management level of the highway has been put forward higher requirements. The freeway on ramp control provides a reference method to the modernization of highway management, especially in the freeway traffic accidents and other emergencies, to maintain traffic order and stability in the clearing time. The freeway on ramp control provides a reference method to the modernization of highway management, especially in the freeway traffic accidents and other emergencies, to maintain traffic order and stability in the clearing time.According to the relevant accident data, using statistical histogram analysis, Q-Q plot, skewness coefficient test, the coefficient of kurtosis test method for analysis of the traffic accident duration distribution, duration of accident prediction method has been explored. This paper describes the theoretical basis of traffic waves, according to the development of traffic waves, the time required to deal with traffic accidents, as well as the scope of traffic wave propagation, that is, the scope of the impact of traffic accidents.According to the short-time traffic flow of nonlinear variation, the has many applicable to short-time traffic flow prediction BP neural network prediction method in Matlab mathematical software, according to short-term traffic flow data and the specific conditions of the construction of the BP neural network model, the completion of the network layer, hidden layer nodes, the training function parameter set is established.Based on short-time traffic flow prediction, according to the accident section capacity determined allowing freeway entrance ramp of the traffic flow, also determines a controlled ramp number according to a traffic accident influence scope, gives the adjustment rate calculation formula and using the VISSIM simulation software of control method was verified. The simulation results show that:on ramp control and traffic flow within the scope of the accident total travel time and delay time are significantly reduced, and can ease the traffic pressure on the main line and make the traffic flow more stable, is conducive to maintain traffic order.