DEVELOPMENT OF TRANSITIONED VERTICAL CURVE. II SIGHT DISTANCE

The mathematical properties of a new vertical curve that consists of a transition curve (cubic polynomial), a parabolic curve, and another transition curve have been presented in a companion paper. The present paper addresses the sight distance characteristics of this new cuurve, called transitioned vertical curve. The minimum sight distance and the required curve length are analytically derived for both crest and sag curves, considering various cases related to the minimum sight distance and the lengths of transition and parabolic curves. Using the developed analytical models, example design graphs are established for the length requirements of the transitioned vertical curve based on the upper range of stopping sight distance presented by the American Association of State Highway and Transportation Officials. The transitioned vertical curve, which resembles the spiraled horizontal curve commonly used in practice, represents an alternative to the simple vertical curve especially for sharp vertical alignments. (A)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/09658564
• Corporate Authors:

  Elsevier

  The Boulevard, Langford Lane
  Kidlington, Oxford  United Kingdom  OX5 1GB
• Authors:
  • Easa, S M
  • Hassan, Y
• Publication Date: 2000-9

Language

• English

Media Info

• Features: References;
• Pagination: p. 565-84
• Serial:
  • Transportation Research Part A: Policy and Practice
  • Volume: 34A
  • Issue Number: 7
  • Publisher: Elsevier
  • ISSN: 0965-8564
  • Serial URL: http://www.sciencedirect.com/science/journal/09658564

Subject/Index Terms

• TRT Terms: Braking performance; Curves (Geometry); Mathematical analysis; Mathematical models; Theory; Vision
• ITRD Terms: 6471: Analysis (math); 1695: Braking distance; 6496: Curve (math); 6473: Mathematical model; 9078: Theory; 2066: Vision
• Subject Areas: Safety and Human Factors;

Filing Info

• Accession Number: 00796609
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, ATRI
• Created Date: Aug 2 2000 12:00AM