RELATIONSHIP BETWEEN TRAFFIC SAFETY AND TRAFFIC VOLUME ON RURAL FREEWAYS AND CONCEPTUAL DEVELOPMENT OF THE LEVEL OF SERVICE OF SAFETY

The relationship between traffic volume, physical characteristics of roads and safety is not well understood or known, at least not with the kind of precision customary in other engineering disciplines. The primary objective of this research was to develop relationships between expected level of safety and traffic exposure for the selected types of rural freeways. These relationships are known as Simple Safety Performance Functions as described in Hauer, Persaud(1). Simple Safety Performance Functions reflect the complex relationship between exposure usually measured in Average Daily Traffic (ADT) and accident count for a unit of road section or a junction over a unit of time. These safety performance functions are referred to as "simple" because they reflect the relationship between exposure and safety for road population sufficiently similar that the only independent variable required is ADT. Level of safety in this study is expressed in terms of the number of accidents per mile over a period of one year and exposure is measured in ADT. The expected level of safety represents normally expected number of accidents per mile of freeway associated with specific level of ADT. Simple Safety Performance Functions were developed for the following facilities: four lane rural freeways in mountainous terrain, six lane rural freeways in mountainous terrain, four lane rural freeways in rolling terrain, and four lane rural freeways on the plains.

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  • Corporate Authors:

    PTRC Education and Research Services Limited

    Glenthorne House, Hammersmith Grove
    London W6OL9,   England 
  • Authors:
    • Kononov, J
  • Conference:
  • Publication Date: 2000

Language

  • English

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Filing Info

  • Accession Number: 00795552
  • Record Type: Publication
  • Report/Paper Numbers: VTI konferens 13A, Part 3
  • Files: TRIS, ATRI
  • Created Date: Jul 29 2000 12:00AM