TOWARD A MORE REALISTIC APPROACH TO THE GEOMETRIC DESIGN OF HIGHWAY VERTICAL CURVES

A major shortcoming of the geometric design methods used in practice is that a deterministic approach is used. Variables like speed, friction and perception and reaction time are actually treated as constants. In this paper the degree of variation incurred if the design process is approached probabilistically is derived in the case of the design of the length of road vertical curves where the stopping sight distance is less than the curve length. An additional shortcoming of the deterministic approach for the design of vertical curves is that the effect of grades on the stopping sight distance is ignored. Exact equations for the stopping sight distance on crest and sag vertical curves are listed and probability density functions fror speed, friction and perception and reaction time are established. Monte Carlo simulation is then applied to obtain the probability density function of the stopping sight distance.

• Supplemental Notes:
  • Full Conference proceedings available only on CD.
• Corporate Authors:

  International Road Federation

  525 School Street, SW
  Washington, DC  United States  20024
• Authors:
  • Cronje, W B
  • Meyer, W E
• Conference:
  • XIIIth World meeting of the International Road Federation
  • Location: Toronto, Canada
  • Date: 1997-6-16 to 1997-6-20
• Publication Date: 1997

Language

• English

Media Info

• Pagination: n.p.

Subject/Index Terms

• TRT Terms: Alignment; Curves (Geometry); Density; Design methods; Geometric design; Highway design; Monte Carlo method; Probability; Stopping sight distance
• Uncontrolled Terms: Probabilistic analysis; Vertical curvature
• Old TRIS Terms: Curve alignment; Density functions
• Subject Areas: Data and Information Technology; Design; Highways; Pavements; I20: Design and Planning of Transport Infrastructure;

Filing Info

• Accession Number: 00751754
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 4 1998 12:00AM