Evaluation of Highway Traffic Safety using Reliability Theory

신뢰도를 활용한 도로시설 교통안전성 평가기법

  • Oh, Heung-Un (Department of Urban & Transportation Engineering College of Engineering)
  • 오흥운 (경기대학교 공과대학 도시.교통공학과)
  • Received : 2016.05.13
  • Accepted : 2016.08.01
  • Published : 2016.08.16


PURPOSES : This paper proposes a reliability index for the safety evaluation of freeway sections. It establishes a reliability index as a safety surrogate on freeways considering speeds and speed dispersions. METHODS : We collated values of design elements including radii, curve lengths, vertical slopes (absolute values), superelevations, and vertical slopes from seven freeway sections in Korea. We also collected data about driving speeds, traffic accidents, and their deviations. We established a reliability index using these variables. RESULTS : The average radii, curve lengths, and superelevations are highly correlated with the incidence of traffic accidents. Deviations in radius and curve lengths show an especially high correlation. The reliability index, derived from speed and speed dispersions of the seven freeway sections, also correlated highly with accidents with a correlation index of 0.63. CONCLUSIONS : Since the reliability index obtained from speed and speed dispersions are highly correlated with traffic accidents, we conclude that a reliability index can be a safety surrogate on freeways considering speeds and speed dispersions together in terms of design and operational levels.


Supported by : 경기대학교


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