About 30 percent of all accidents on rural roads occur at bends. This may not appear surprising, because of the influence of centrifugal force and restricted visibility, but more subtle factors can determine their safety. Investigations of 'safe' and 'hazardous' bends has indicated that the main difference between them was not whether their curvature was large or small, but whether it was constant or variable. This led to the hypothesis that drivers have more difficulty perceiving the curvature of a transitional bend, because it can deceive them into maintaining an excessive speed. Three acute, accident-prone bends were therefore converted from transitional to circular alignment. Comparing equal before-and-after periods, accidents have been reduced significantly, by about 80 percent, and cost-effectiveness has also been high. These results suggest that widespread prevention of accidents at sub-standard bends would be simple and inexpensive, and that design codes should no longer recommend the use of transition curves.

  • Availability:
  • Corporate Authors:

    Printerhall Limited

    29 Newmart Street
    London W1P 3PE,   England 
  • Authors:
    • Stewart, D
  • Publication Date: 1990-2

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00496364
  • Record Type: Publication
  • Source Agency: Printerhall Limited
  • Files: TRIS, ATRI
  • Created Date: Aug 31 1990 12:00AM