Study On Impact Of Vehicle Speed Difference On Road Traffic Safety

With the rapid development of China economy, the function of road transport is more andmore significant in the national economy. As a fast and efficient transportation mode,highway has been made a rapid development under the government’s support. However, thereare a series of issues appeared with the rapid development, such as high accident rate,environmental pollution and lack of management. Among them, the vehicle speed differenceis one important reason of accident rate increasing and traffic flow disorder.Vehicle speed difference is the result of driver’s subjective choice. However, if this differenceis too large will increase accident rates and disorder traffic flow, it’s not conducive to roadtraffic safety. Through the analysis of different types of roads found that, the speed and speeddifference on the highway are greater than ordinary road, and the consequences are moreserious too. Therefore, the study of speed difference is very important to enhance the roadtraffic safety, in particular the highway’s safety.The purpose of this research is to explore the characteristics of the vehicle speed difference,generation mechanism and the impact of speed difference on road traffic safety. In this paper,the topic is analyzed and discussed by the methods of theoretical analysis and practical datacollection. Refers to the three parameters to represent the vehicle speed difference: SpeedStandard Deviation (hereinafter referred to as SD), the difference between the85th percentilespeed and the15th percentile speed (hereinafter referred to as V85-V15), and coefficient ofvariation (hereinafter referred to as CV). Use three parameters to characterize the trafficsafety: the number of traffic accidents, Vehicle Need Safety Distance and traffic flow averagespeed, to reflect the impact of speed difference on road traffic safety by analyzingrelationship between speed difference parameters and road traffic safety parameters.Summarize general rules of vehicle speed difference phenomena based on the investigationand analysis of traffic flow data and the impact of vehicle speed difference on road trafficsafety.