Mix Design Using Asphalt Millings

Details

• Creators:
  Issa, Rita I ; Zaman, Musharraf M. ; Miller, Gerald A.
• Corporate Creators:
  University of Oklahoma
• Corporate Contributors:
  United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Anionic Emulsified Asphalt Asphalt Pavements Cationic Emulsified Asphalt Cement Content Cold In-place Recycling Cold Mix Paving Mixtures Mix Design
• Publication/ Report Number:
  FHwA/OK 00(04)
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Oklahoma
• Corporate Publisher:
  Oklahoma. Department of Transportation
• Abstract:
  A field demonstration project was undertaken by the Oklahoma Department of Transportation to investigate the performance of an asphalt overlay constructed using recycled asphalt millings and the cold mixed, cold laid system. A 1.9-km (1.2-mi) section of the US-64 North frontage road in Pawnee County was rehabilitated with a 5-cm (2-in.) thick overlay using 100% recycled asphalt millings. The section was divided into four approximately equal length test sections. A different type of emulsion was used to rejuvenate the asphalt millings for each test section. The purpose was to determine the relative performance of each emulsion type and construction method used in this recycled asphalt pavement (RAP) project. A laboratory investigation was carried out to accomplish two major tasks: the first task was to determine the optimum emulsion and moisture contents of RAP mixes prepared with four different types of emulsions; the second task was to investigate the effect of adding portland cement to RAP mixes, thus producing a cement-emulsion composite. One of the objectives of this study was to document the behavior of RAP mixes as affected by the addition of portland cement, and to find the optimum emulsion and cement contents. Achieving an adequate compaction is crucial to the successful performance of a cold mixed, cold laid overlay. The degree of compaction can greatly vary depending upon rolling pattern, speed, equipment, compaction dynamics, and characteristics of RAP mixes. From post-construction site visits, it was evident that the polymer modified anionic (PMA) emulsion section performed better than the other sections. A PMA mix containing 2% free moisture and 2% emulsion was found to have the highest dry stability value; however, this mix had a lower retained stability than a comparable mix prepared with polymer modified cationic (PMC) emulsion. For samples prepared from cement-emulsion composite, both dry and soaked stability values increased as cement content increased. The addition of portland cement, however, affected the stability value of samples cured under soaked conditions much more than those cured under dry conditions. The introduction of as little as 1% of portland cement to RAP mixes doubled the retained stability of specimens, as compared with a RAP mix rejuvenated with high float emulsion (HFE-300). The cold mixed, cold laid process of pavement rehabilitation holds significant promise for the future. The current technology, however, needs improvement and refinement through further laboratory and field studies.
• Format:
  PDF
• Funding:
  2148
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:23914c56c8cdaef670e8646e90f9df77db3a2b38af6299ec1730438272523d03897e398c34a98bee884ae9f0e5816b48e1eb565b201554d45cda82622e337574
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/87973/dot_87973_DS1.pdf
• File Type:
  [PDF - 7.55 MB ]