A comprehensive study on pavement edge line implementation.

Details

• Creators:
  Sun, Xiaoduan ; Das, Subasish
• Corporate Creators:
  University of Louisiana at Lafayette. Department of Civil and Environmental Engineering
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  • Edge lines
  • Road markings
  • Traffic control devices
  • Pavements
  • Collisions
  • Traffic safety
  • Highway safety
• Publication/ Report Number:
  FHWA/LA.13/508
• Resource Type:
  Tech Report
• Geographical Coverage:
  Louisiana
• Corporate Publisher:
  Louisiana. Dept. of Transportation and Development
• Abstract:
  The previous 2011 study “Safety Improvement from Edge Lines on Rural Two-Lane Highways” analyzed the crash data of ; three years before and one year after edge line implementation by using the latest safety analysis statistical method. It ; concluded that placing pavement edge lines on rural two-lane highways in Louisiana can not only change the lateral ; positions of the vehicles but also reduce crashes. The Crash Modification Factor (CMF) for edge line on narrow, rural two-lane highways is 0.78. Considering the decreasing trend in crashes in the state for the past three years, the modified CMF is ; 0.83, which implies that, on average, implementing edge lines can reduce 17% of crashes. ; As an extension of the 2011 project, this study not only used two more years of crash data for the after time period but also ; applied the Empirical Bayes (EB) method in the analysis to estimate the crash reduction factors. Moreover, crash ; characteristics analysis is performed in this study to compare the difference before and after edge line implementation. ; Additionally, this project performed benefit and cost analysis. ; By considering the safety trend in Louisiana, the final estimated CMF is 0.85, which means there is a 15% expected crash ; reduction in edge line implementation on narrow, rural two-lane highways. The statistically estimated standard deviation for ; the CMF is 0.039. The crash reduction is consistent in all crash types and particularly significant in single vehicle crashes. ; Most of single vehicle crashes are ROR crashes, which is the exact type of crash targeted by edge line implementation. ; The benefits overwhelmingly offset the cost with edge line implementation. The most conservative estimation for benefit ; and cost ratio is 19. ; This project recommends the use of edge lines on narrow rural two-lane highways whenever it is financially feasible and ; operationally feasible.
  More +
• Format:
  PDF
• Funding:
  LTRC Project Number: 13-2P;SIO Number: 30000730
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/27322/dot_27322_DS1.pdf
• File Type:
  [PDF - 294.36 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:31449affab78a6197ab2ae548c2a52bce156e4d274f9e1ac4c9d3ad863c9bc91aac170493490d530415d749865a89ac55644c19ee07f1fd7447997fbee3e612c