Safety Effectiveness of Chevrons and Postmounted Delineators in Reducing Lane-Departure Crashes

Lane-departure crashes are the most predominant fatal crash type in Kansas. Therefore, attempts have been taken to reduce lane-departure crashes by implementing lane-departure countermeasures. This study was conducted to estimate crash modification factors (CMFs) to evaluate the safety effectiveness of chevrons and postmounted delineators which are commonly employed as countermeasures on two-lane curved road segments. A total of 500 two-lane curved road segments were considered and the crash frequencies were obtained for all lane-departure crashes and fatal and injury lane-departure crashes from 2013 to 2015. The cross-sectional method was used by developing generalized linear regression models assuming Poisson error distribution. To increase the representativeness of the model, driver, and environment-related variables were incorporated into the models in addition to road geometric and traffic-related variables. Estimated regression parameters of the respective countermeasures were used to calculate the CMFs. Based on the results, it was seen that both chevrons (CMF=0.67) and post-mounted delineators (CMF=0.68) reduce all lane-departure crashes. Furthermore, it was seen that both chevrons (CMF=0.65) and postmounted delineators (CMF=0.64) have an even higher crash reduction effect on fatal and injury lane-departure crashes. These results can be used as a decision-making tool when implementing countermeasures on two-lane curved road segments where high crash frequencies are observed.


  • English

Media Info

  • Media Type: Web
  • Features: References;
  • Pagination: pp 336-345
  • Monograph Title: International Conference on Transportation and Development 2018: Connected and Autonomous Vehicles and Transportation Safety

Subject/Index Terms

Filing Info

  • Accession Number: 01867083
  • Record Type: Publication
  • ISBN: 9780784481530
  • Files: TRIS, ASCE
  • Created Date: Dec 13 2022 10:05AM