INTERIM REPORT ON NATIONAL EXPERIMENTAL AND EVALUATION PROGRAM (NEEP) PROJECT NO 10-REDUCING CRACKING IN BITUMINOUS OVERLAYS

The individual States' evaluations of those test features suggested by the Federal Highway Administration are set forth. Experience in the use of Reclamite as asphalt rejuvenating agent is described. This may be sprayed on the existing pavement prior to overlay in accordance with manufacturer's recommendation, or the existing surface may be heated and scarified followed by an application of Recalmite and the overlay. Arizona noted good performance with Reclamite and sections treated with Petroset were noted to be virtually crack free. Other states indicate dissatisfaction with Reclamite in the sealing of reflection cracks, Oklahoma reports a decrease in skid resistance. The use is discussed on Structofors, a woven polyester fabric applied to the existing asphalt pavement surface followed by the overlay. No reflection cracks were reported in some areas while others claimed cracks have appeared in all treated sections. Reports are also made regarding the use of Petromat, a nonwoven polyproylene fabric. Most states noted no cracks with the material, and good bond was evident between the fabric and overlay. Comments are made on plant mix seal (open graded asphalt fraction course) placed in about 5/8 inch thick layer on the existing asphalt pavement followed by the overlay. The seal has been considered effective in reducing reflective cracking. Evaluatory comments are also presented on the following: asphalt emulsion slurry placed on the existing asphalt pavement surface prior to the overlay; the application of Petroset AT Geotechnic Emulsion at the manufacture's recommended rate on the new overlay; and rubberized emulsion slurry seal. In the last (strain relieving interlayer), an asphalt emulsion slurry seal containing (about 23 percent by weight of aggregate) shreds from devulcanized rubber tires is placed on the existing asphalt pavement surface followed by the overlay.

  • Corporate Authors:

    Transport and Road Research Laboratory

    Environment Division, Old Wokingham Road
    Crowthorne RG11 6AU, Berkshire,   England 
  • Publication Date: 1975-6

Media Info

  • Pagination: 15 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00098478
  • Record Type: Publication
  • Report/Paper Numbers: Intrm Rpt.
  • Files: TRIS
  • Created Date: Sep 30 1975 12:00AM