Moisture Susceptibility of Warm-Mix Asphalt with Reclaimed Asphalt Pavement Material

Sustainable technologies like warm-mix asphalt (WMA) and reclaimed asphalt pavement (RAP) material are well-known in the asphalt paving industry. Even though RAP has been termed as one of America’s most recycled materials, its greater use is limited due to adverse effects on workability, fatigue and thermal cracking stemming from the presence of aged binder. While WMA is relatively new in the pavement industry, its potential for environmental benefits and other advantages resulting from its lower production temperatures are recognized. However, WMA mixtures are also plagued by concerns over moisture susceptibility and permanent deformation. Combining WMA and RAP may allow for the use of greater amounts of RAP without resulting in major changes to the job mix formula or compromising on mixture performance. In this study, the performance of WMA mixtures—Evotherm 3G and PTI Foamer—with 0%, 20% and 40% RAP are compared with the corresponding hot-mix asphalt (HMA) RAP mixtures. Moisture susceptibility was evaluated using Tensile Strength Ratio (TSR) and dynamic modulus (E*) stiffness ratio (ESR). Pavement performance predictions were made using the AASHTOWare Pavement ME Design software with surface mixture dynamic modulus evaluated at 4%, 7% unconditioned and 7% moisture conditioned air voids content. The results indicate that WMA mixtures even with 40% RAP performed well without a change in binder grade.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFK40 Standing Committee on Surface Requirements of Asphalt Mixtures.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Malladi, Haritha
  • Kusam, Abhilash
  • Tayebali, Akhtarhusein A
  • Khosla, N Paul
• Conference:
  • Transportation Research Board 96th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2017-1-8 to 2017-1-12
• Date: 2017

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 13p
• Monograph Title: TRB 96th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Air voids; Dynamic modulus of elasticity; Reclaimed asphalt pavements; Stiffness; Tensile strength; Warm mix paving mixtures
• Identifier Terms: AASHTOWare (Software)
• Uncontrolled Terms: Moisture susceptibility
• Subject Areas: Highways; Materials; Pavements;

Filing Info

• Accession Number: 01628583
• Record Type: Publication
• Report/Paper Numbers: 17-02135
• Files: TRIS, TRB, ATRI
• Created Date: Mar 7 2017 5:27PM