Identification of Aggregates for Tennessee Bituminous Surface Courses, Phase IV and Amendment 1

As part of an overall plan to increase the Hot Mix Asphalt (HMA) resurfacing cycle time, the Tennessee Department of Transportation (TDOT) initiated a project to pair aggregate polish resistance with pavement functional needs in 1992. A new pre-evaluation procedure for aggregate polish resistance was developed and named the Tennessee Terminal Textural Condition Method (T3CM). Correlations between T3CM and pavement skid performance were far superior to the correlations for percent silica and BPN9 to pavement skid performance. Unfortunately, the T3CM was labor intensive. Results of the recently developed quicker and easier Micro-Deval Voids at 9 hours (MDV9) method were found to not be significantly different from those of T3CM in a paired t-test at the 95% confidence interval on 31 Tennessee aggregates. The MDV9 procedure requires only three hours of technician time compared to approximately 47 hours for T3CM. Further, sample size was reduced from 72 to 10 kg. Finally, the MDV9 had a coefficient of variation of 0.42% in a 30 replicate evaluation of a Tennessee proven-performing limestone. The research team therefore recommends that the quicker, easier MDV9 be used as a pre-evaluation procedure for aggregate sources and as a verification test for random aggregate lots. The research team recommends that TDOT Type 1 and Type 2 aggregates have a minimum TTC/MDV9 value of 43.5. There is insufficient terminal skid data available to recommend a minimum TTC/MDV9 value for TDOT Type 3 aggregates.

Language

  • English

Media Info

  • Media Type: Print
  • Edition: Final Report
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 52p

Subject/Index Terms

Filing Info

  • Accession Number: 01000058
  • Record Type: Publication
  • Report/Paper Numbers: TNSPR-RES1149
  • Contract Numbers: CUT 195
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: May 6 2005 4:16PM