The permanent deformation characteristics of a dense bitumen emulsion macadam (DBEM), have been studied in the laboratory using the repeated load axial test (RLA). A conventional emulsion and SBS and EVA polymer modified emulsions have been used to investigate the influence of polymer modification on the resistance of mixtures to permanent deformation. The base binder, which was a 100 pen straight run bitumen, together with a 200 pen binder were used in the study to prepare equivalent hot-applied mixtures for comparison. The binder rheological properites were evaluated in a dynamic shear rheometer under temperature and frequency conditions commensurate with those in the RLA. The binder evaluation parameters used in the study were similar to those advocated by the US Strategic Highway Research Program (SHRP) for assessment of the material's resistance to permanent effect of polymer modification on the performance of the DBEM as compared to the hot-applied reference mixes. However, questions are raised concerning the applicability of the SHRP protocol of ranking binders according to their permanent deformation characteristics. (A)


  • English

Media Info

  • Features: References;
  • Pagination: p. 103-11
  • Serial:
    • Volume: 135
    • Issue Number: 2

Subject/Index Terms

Filing Info

  • Accession Number: 00766809
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, ATRI
  • Created Date: Aug 2 1999 12:00AM