Some important projects involving recycling of paving materials are reviewed and discussed in relation to the materials utilized, and comments are made on the economics of recycling. Two types of construction operations are in general use: inplace recycling, and recycling through a central plant. The materials to be recycled include: unstabilized base (subbase) and thin surfacing materials; stabilized base (subbase) and thin surfacing material, asphalt aggregate surface mixtures, portland cement concrete surface mixtures, and mixtures of existing base (subbase) thin surface and new material. Experiences in Florida and Michigan (unstabilized base course), Wisconsin and Texas (stabilized base), Michigan, District of Columbia, California, Texas and Louisiana (Portland Cement Concrete), California, Indiana, Iowa, Utah, Nevada, Texas and Massachusetts (asphalt concrete) are outlined. Among the projects discussed is the in-place cold recycling of asphalt concrete in Texas, where preliminary tests were performed relating to rejuvenating hardened asphalts. Results of these tests indicate that 20 penetration asphalt can be rejuvenated to a 70 penetration by the addition of softening agent. Experience indicates the need for research in the following areas: air pollution associated with recycling asphalt stabilized mixtures in hot-mix operation through a central plant; guidelines to aid in decision-making; establishment of costs to aid in selection of the appropriate rehabilitation alternative; comparison of properties of recycled mixtures with those of conventional mixtures; and improvement of in-place recycling equipment.

  • Corporate Authors:

    Texas State Department of Highways & Public Transp

    P.O. Box 5051
    Austin, TX  United States  78763
  • Authors:
    • Epps, J A
    • O'Neal, R J
  • Publication Date: 1975-12

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 30 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00132916
  • Record Type: Publication
  • Report/Paper Numbers: RR 214-12 Res. Rept.
  • Created Date: Jun 5 1976 12:00AM