Rubber/ bitumen digestions: manufacture and properties

The service performance of sprayed surface treatments laid where traffic stressing is severe or where the existing pavement is cracked can be significantly improved if comminuted scrap rubber is digested in the bitumen before spraying. Work has been done to identify the factors which are of importance in optimising binder performance. A simple and rapid test procedure was developed to measure the response under loading conditions approaching those which are important in pavement service. The procedure is to subject a prism of the binder at 60 degrees c to a shear strain of 1.0 In creep and then determine the elastic recovery when the stress is removed. The most important factor affecting elastic recovery was found to be the morphology of the rubber particles as determined by the comminution process used in their manufacture. A simple bulk density test was used to characterise this morphology. Digestions of natural (truck tyre) rubber are generally superior to those incorporating synthetic (car tyre) rubber but are more affected by changes in the time or temperature of digestion. Where a cryogenic comminution process had been used only digestions of natural rubber particles produced a significant improvement in bitumen properties. Elastic recovery of strain is linearly related to rubber concentration. As rubber particle size decreases elastic recovery of the digestions increases (a).


  • English

Media Info

  • Pagination: 35-53
  • Monograph Title: The properties of paving bitumens in relation to their performance in road surfacings

Subject/Index Terms

Filing Info

  • Accession Number: 01438578
  • Record Type: Publication
  • Source Agency: ARRB
  • ISBN: 869100203
  • Files: ATRI
  • Created Date: Aug 24 2012 9:37PM