Development of an Improved Method for Determining Advisory Speeds on Horizontal Curves

Horizontal curves are an integral part of the highway alignment. However, a disproportionately high number of severe crashes occur on them. One method transportation agencies use to reduce the number crashes at horizontal curves is the installation of curve warning signs which post an appropriate advisory speed. Appropriate curve advisory speeds can be determined using several methods. Some of these methods are time-consuming to perform and are error-prone. The purpose of this research was to find the most efficient and accurate data collection method for determining curve advisory speeds. Several processes were developed and tested. They were then validated against the results of a manual process referred to as the Direct Method and other traditional methods (such as the ball-bank indicator), which are generally assumed to produce accurate results. Comparing the results of these methods allows researchers to evaluate their accuracy and usefulness for setting advisory speeds. The results illustrate the potential of a more user-friendly methodology that allows for efficient and accurate data collection. The advisory speeds determined by this research will assist the Kentucky Transportation Cabinet to properly sign horizontal curves. Previous research suggests that posting appropriate advisory speeds results in a safer driving experience.

  • Record URL:
  • Corporate Authors:

    University of Kentucky, Lexington

    Kentucky Transportation Center
    College of Engineering, 176 Raymond Building
    Lexington, KY  United States  40506-0281

    Kentucky Transportation Cabinet

    State Office Building, 200 Mero Street
    Frankfort, KY  United States  40622

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Green, Eric R
    • Agent, Ken R
    • Lammers, Erin
  • Publication Date: 2016-7


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 39p

Subject/Index Terms

Filing Info

  • Accession Number: 01632319
  • Record Type: Publication
  • Report/Paper Numbers: KTC-16-14/SPR15-507-1F
  • Contract Numbers: SPR15-507
  • Created Date: Apr 15 2017 6:46PM