Exploration on Speed-limit Signs of Traffic Accident Section on Freeways

In order to improve freeways traffic safety, reduce staff and vehicles casualties and prevent secondary traffic accidents, the accident site section on freeway is divided into six regions of the warning zone, the upstream transition zone, the buffer zone, the accident zone, the downstream transition zone and the termination zone. Establish the warning zone speed-limit model by considering the relevant factors of driver's field of vision and transportation distance of visual cognition and then speed-limit programs are proposed according to the warning area speed-limit model. Speed-limit signs of the warning zone take phased settings based on both of those. The results show that the proposed warning area speed limit model conforms to the actual need, decision science, and having important practical value for freeway traffic safety.