Development of laboratory mix design procedures for RAP mixes.

Details

• Creators:
  Cooley, Jr., L. Allen ; Williams, Kevin
• Corporate Creators:
  Burns Cooley Dennis, Inc.
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  • Mix design
  • Asphalt pavements
  • Recycled materials
  • Hot mix paving mixtures
  • Binders
  • Laboratory tests
  • Blending
  • Stiffness
• Publication/ Report Number:
  FHWA/MS-DOT-RD-13-246 ; MS-DOT-RD-13-246
• Resource Type:
  Tech Report
• Geographical Coverage:
  Mississippi
• Corporate Publisher:
  Mississippi. Dept. of Transportation
• Abstract:
  The objective of this study was to evaluate the amount of blending that occurs between RAP and virgin asphalt ; binders in plant produced HMA in which RAP is incorporated. This objective was accomplished by testing plant ; produced mixture from three different on-going HMA projects. Two of the three projects incorporated 15 percent ; RAP while the third project incorporated 30 percent. Samples were brought back to the laboratory and subjected ; to a staged extraction/recovery process. Asphalt binder recovered from each stage was subjected to Dynamic ; Shear Rheometer testing in order to determine the high failure temperature using a criterion of 2.20 kPa. ; Based upon the research approach, it was concluded that majority of asphalt binder was extracted and recovered ; from the first stage of washing. The amount of asphalt binder extracted/recovered from successive washes ; decreased, except for the last stage. For mixes containing 15 percent RAP, the asphalt binder was not significantly ; affected by the RAP though there was a slight increase in failure temperature through the staged washes, except ; for the last stage. The majority of the asphalt binder from the 30 percent RAP mixture was removed during the ; first stage of washing. The stiffness of the asphalt binder after Wash 1 was higher for this 30 percent RAP mix ; than for the 15 percent RAP mix; however, the increase in stiffness was not large. The increase in stiffness for ; successive washes was higher for the 30 percent RAP mix than for the 15 percent RAP mixes. Based upon these ; findings, it was concluded that partial blending between RAP and virgin asphalt binders when RAP is ; incorporated into plant produced HMA.
  More +
• Format:
  PDF
• Funding:
  State Study No. 246 ; Project No. SPR-1(60) 106266 166000
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/27481/dot_27481_DS1.pdf
• File Type:
  [PDF - 581.34 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:4cda9ca85971360299700526f6fa7f216ddd248c6e292e6bafde9398ebf9d7d2