Traffic Risk Assessment of Freeway On-Ramp and Off-Ramp Areas Based on Simulation Analysis

Abstract

In order to improve safety of freeway on-ramp and off-ramp areas, the operating characteristics of traffic flows and accident cause on freeway on-ramp and off-ramp areas were analyzed. The risk level was changed from two-dimension vector to one-dimension variable based on the critical deceleration and unsafe degree. The deceleration risk and unsafe density parameter as traffic risk assessment index were put forward, and then the traffic risk quantitative assessment models were established. According to the safety risk management theory, the risk classification description and assessment were built up. Applying the microscopic traffic simulation technique, the suggested values of the traffic control standard of on-ramp and off-ramp areas were also proposed. At last, a case study was illustrated for the risk analysis through simulating the traffic flows. The results suggested that the traffic risk assessment index and the assessment method are accurate and effective. Furthermore, it can lay a theoretical foundation for the establishment of the dynamical traffic control and management measures.