MODIFICATION OF ASPHALT BINDERS AND ASPHALT CONCRETE MIXES WITH CRUMB AND CHEMICALLY DEVULCANIZED WASTE RUBBER

For this study of the modification of asphalt binders with crumb and devulcanized waste rubber, rubber digestion aids were investigated for their ability to devulcanize waste tire crumbs. It was found that none of the commercially available chemical agents were able to totally devulcanize the crumb rubber. However, high yields of devulcanization were obtained with chlorothiophenols. The devulcanized and crumb rubbers were added to asphalt binders, and their low temperature performance was studied. It was found that the fracture toughness of the devulcanized rubber system was higher than that for both the control asphalts and a commercially available oxidized rubber system. Toughening is mainly due to crack pinning and shear yielding mechanisms for crumb rubber systems. However, only enhanced shear yielding mechanisms are responsible for the increase in toughness found in devulcanized rubber systems. Further work on the asphalt-aggregate mix should tell us if the improved performance of devulcanized binder systems will give enhanced pavement performance.

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 56-63
  • Monograph Title: Recycled tire rubber and other waste materials in asphalt mixtures
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00715664
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Jan 26 1996 12:00AM