Optimizing Laboratory Curing Conditions for Hot Mix Asphalt to Better Simulate Field Behavior

Details

• Creators:
  Arras, Benjamin ; Sreeram, Anand ; Abdallah, Imad N. ; Nazarian, Soheil ; Bhasin, Amit ; Hazlett, Darren
• Corporate Creators:
  University of Texas at El Paso. Center for Transportation Infrastructure Systems ; University of Texas at Austin. Center for Transportation Research
• Corporate Contributors:
  Texas Department of Transportation. Research and Technology Implementation Office ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Aging (Materials) Asphalt Concrete Asphalt Mixtures Long-term Aging Concrete Curing Cracking Hot Mix Asphalt Laboratory Tests Mix Design Rutting Short-term Aging
• Publication/ Report Number:
  FHWA/TX-23/0-7061-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Edition:
  January 2020 – January 2023
• Corporate Publisher:
  Texas Department of Transportation. Research and Technology Implementation Office
• Abstract:
  The engineering properties of asphalt mixtures change with time. Shortly after placement, asphalt concrete (AC) layers are more susceptible to rutting. As the pavement ages, the AC layer becomes stiffer, brittle, and thus more susceptible to cracking. Current protocols provide guidelines for the selection of materials, the determination of the material proportions (e.g., aggregates and binder content), and the evaluation of the engineering properties (e.g., cracking and rutting potentials) of any given asphalt mix design. However, these protocols do not provide any check on the impact of aging on the mixture. This study investigated existing and novel laboratory methods to determine protocols that simulate the two aging states needed to design an asphalt mixture to resist rutting and cracking and provide information on how curing affects the physical and engineering performance of binders and mixtures. This study leveraged existing research studies and available performance data along with a systematic test matrix to optimize the curing conditions. The wide range of tests conducted in this study indicated that a minimum time to achieve levels of long-term aging using an optimized laboratory protocol would be close to 24 hours. The steady state of aging for ranking different mixes may be adequately achieved after a period of 24 hours (including 2 hours of short-term aging) under Protocol 1 i.e., loose mixture aging in a conventional laboratory oven. The efficiency of other aging protocols using pressure and oxidated gases have been demonstrated. These methods can be used to more accurately characterize the performance of mixes under long-term aging within a time frame of 24 to 48 hours.
• Format:
  PDF
• Funding:
  Project No. 0-7061
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:2b9b4fa3c7e1d5e93153ad276f280dc5e60eed8f26906f1ab58760e36ae69a6320d734435f07c44d520a37ba1dac3c43e8d10dcb6f2ae949e4993e4eadb6104e
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/80030/dot_80030_DS1.pdf
• File Type:
  [PDF - 3.83 MB ]