Abstract
This study explores low-friction issues in specific asphalt pavements utilizing dolomite aggregates within an Indiana Department of Transportation district. It examines the frictional characteristics of these aggregates, concentrating on initial friction (PSV0) and long-term friction retention (PSV10). Employing a mix of laboratory tests, field data analysis, and statistical modeling, the research assesses how mechanical, physical, and chemical properties influence the overall friction behavior of dolomite aggregates.
The evaluation of Design Mix Formulas (DMFs) revealed no statistically significant effect on pavement friction, with variations more closely tied to aggregate quality and construction practices rather than the mix design itself. Inconsistent friction results were observed in projects using the same DMF, underscoring the importance of aggregate quality. The transition from Superpave4 to Superpave5 showed no correlation with friction outcomes. Chemical property analyses highlighted magnesium (Mg) content as critical in determining initial and retained friction performance, identifying an optimal Mg range of 11.35%-12.63% (MgO: 18.82%-20.94%) for a balance between initial friction and long-term durability. Field samples were compared with laboratory results, indicating that low PSV0, rather than excessive wear, primarily contributed to low friction in certain road sections. Additionally, a moderate correlation (0.51) between friction loss (ΔPSV) and average annual daily traffic (AADT) suggests that high-traffic roads are more prone to polishing effects. The study also assessed the role of secondary aggregates, such as steel slag, in improving friction retention, proposing that blended aggregates may enhance long-term performance.
Recommendations include optimal Mg content thresholds, effective aggregate selection strategies, and enhanced quality control and assurance measures during construction. Emphasizing the need for adequate aggregate angularity and the inclusion of steel slag, these findings provide a foundation for future research and policy development aimed at improving long-term pavement friction performance.
Keywords
hot mix asphalt, pavement friction, surface texture, dolomite aggregate, mechanical property, physical property, chemical property
Report Number
FHWA/IN/JTRP-2025/23
SPR Number
4751
Sponsoring Organization
Indiana Department of Transportation
Performing Organization
Joint Transportation Research Program
Publisher Place
West Lafayette, Indiana
Date of Version
2025
DOI
10.5703/1288284317909
Recommended Citation
Bao, J., Peng, C., Hu, X., Jiang, Y., Lee, J., Li, S., & Shah, A. (2025). Investigation of low friction on asphalt pavements (Joint Transportation Research Program Publication No. FHWA/IN/JTRP-2025/23). West Lafayette, IN: Purdue University. https://doi.org/10.5703/1288284317909
SPR-4751 Technical Summary