RES2025-09: Retro-reflectivity Life of Pavement Markings

Pavement markings are essential for delineating travel lanes and enhancing road safety by offering near-field lane positioning and far-field alignment guidance. They are designed for day and night visibility, helping drivers maintain correct lane discipline [1]. In Tennessee, pavement markings are typically made from two material types that are paints and thermoplastics, with retro-reflectivity being a critical performance indicator. The Tennessee Department of Transportation (TDOT) mandates that white stripes must have a minimum retro-reflectivity of 300 mcd/m²/lux and yellow stripes 200 mcd/m²/lux, 45 days post-application [2]. In 2017, updates to these standards were proposed through a Supplemental Notice of Proposed Amendments (SNPA), revising the initial 2010 proposal. This revision specified that longitudinal markings must maintain a minimum retro-reflectivity of 50 mcd/m²/lx, measured with the 30-meter geometry method using specific entrance and observation angles. For roadways with a speed limit of 70 mph, the requirement increases to 100 mcd/m²/lx [3]. The research objectives are to: (1) Summarize current pavement markings implementation including material selection, retro-reflectivity lifespan concerns, and potential improvements. (2) Identify the root causes of retro-reflectivity degradation of pavement markings (due to factors like weather, UV exposure, traffic, etc.) and potential solutions. (3) Conduct field measurements of pavement marking retro-reflectivity on select Tennessee pavements, considering speed limits, traffic levels, and weather conditions. (4) Laboratory evaluation of the retro-reflectivity of various pavement markings on different pavements, examining the impact of material types, dimension, and environmental factors. (5) Analyze how these factors affect the retro-reflectivity of pavement marking. Then, correlate the field measurements and laboratory tests through benchmarking. (6) Develop a comprehensive guideline of optimal service life for each type of pavement marking and cost-effective strategies for restriping to maintain safe, reflective pavement markings statewide.

• Record URL:
  https://www.tn.gov/content/dam/tn/tdot/research/2023-24-25-one-pagers/2025---revised-one-pagers/RES2025-09%20Summary.pdf

Language

• English

Project

• Status: Active
• Funding: $250000
• Contract Numbers:

  RES2025-09

• Sponsor Organizations:

  Tennessee Department of Transportation

  James K. Polk Building
  Fifth and Deaderick Street
  Nashville, TN  United States  37243-0349
• Managing Organizations:

  Tennessee Department of Transportation

  James K. Polk Building
  Fifth and Deaderick Street
  Nashville, TN  United States  37243-0349
• Project Managers:

  Chandler, Laura

• Performing Organizations:

  University of Tennessee, Knoxville

  Center for Transportation Research
  Conference Center Building
  Knoxville, TN  United States  37996-4133
• Principal Investigators:

  Huang, Kai

• Start Date: 20240901
• Expected Completion Date: 20260831
• Actual Completion Date: 0
• USDOT Program: Accountability
• USDOT Program: Advanced Materials/Structural Safety
• USDOT Program: Behavioral Safety Research
• USDOT Program: Highway Safety Research
• Subprogram: Advanced Materials
• Subprogram: Center for Transportation Research
• Subprogram: Highway Safety

Subject/Index Terms

• TRT Terms: Retroreflectivity; Road markings; Service life
• Geographic Terms: Tennessee
• Subject Areas: Design; Highways; Pavements;

Filing Info

• Accession Number: 01932354
• Record Type: Research project
• Source Agency: Tennessee Department of Transportation
• Contract Numbers: RES2025-09
• Files: RIP, STATEDOT
• Created Date: Sep 30 2024 4:23PM