Expressway Traffic Accident and Matrix of Vehicle Speed

By analyzing the traffic accident rate and operating speed on foreign expressways, this article tells the prophase method that we do research about forecasting the traffic accident rate based on operating speed of vehicles. Based on the prophase investigative method,taking into consideration of two factors of the velocity and the velocity gradient at the same time, it remedies the limitation that the model of prophase accident rate is short of the influencing factors, and analyses the influencing factors and manipulative parameters. In addition, this article introduces the new predicting model of expressway traffic accident and gives some advises on how to set up the matrix of traffic accident injury.