Short-Term Aging of Hot Mix Asphalt

Details

• Creators:
  Aschenbrener, Timothy B. ; Far, Nava
• Corporate Creators:
  Colorado. Department of Transportation
• Corporate Contributors:
  United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  • Hot mix asphalt
  • Tracking systems
  • Absorption
  • Alternatives analysis
  • Field studies
  • Laboratory tests
  • Time duration
  • Asphalt cement
  • short-term aging
  • asphalt absorption
  More +
• Publication/ Report Number:
  CDOT-DTD-R-94-11
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Edition:
  Final Report
• Corporate Publisher:
  Colorado. Department of Transportation
• Description:
  Short-term aging is defined as the hardening or stiffening of the asphalt cement as well as the asphalt cement absorption into the aggregate as a result of the construction process. The asphalt cement ages during construction when the hot mix asphalt (HMA) is at elevated temperatures. This occurs during mixing, storage, hauling, placing, and compaction operations. The purpose of this study was to investigate the length of time to short-term age samples mixed in the laboratory in order to simulate the short-term aging that is received in the field. This was done by: 1) measuring the amount of time the HMA stays at elevated temperatures in the field, 2) comparing the quantity of asphalt absorption into the aggregate between field produced and laboratory mixed samples, and 3) comparing test results from the Hamburg wheel-tracking device between field produced and laboratory mixed samples. A previous study has shown the Hamburg wheel-tracking device is very sensitive to short-term aging. Information gathered from the field indicated that the HMA stayed at elevated temperatures for approximately 1 to 2 hours for a majority of projects. Based on test results from asphalt absorption, the short-term aging time should be 2 to 4 hours; based on test results from the Hamburg wheel-tracking device, the short-term aging should be between 1 and 3 hours. As expected, the length of short-term aging in the field is quite variable because of the variable field conditions and material properties. It was recommended to short-term age samples mixed in the laboratory for 2 hours to simulate the field aging.
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/93739/dot_93739_DS1.pdf
• File Type:
  [PDF - 11.27 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:e3affcf9e983362f95c73bf032d2fb3ed6aa4f20e9df09281a6d6e58b9085c0110379040f4894fcb17e8e8035ce08e36fffa12317a3e4e99f7e62ea40da66262