EVALUATION OF PROPRETIES OF AC-20 ASPHALT CEMENTS

In 1971, the Pennsylvania Department of Transportation adopted viscosity graded asphalt cement specifications similar to AASHTO M 226-70. AC-20 asphalt cement, most commonly used for paving in Pennsylvania, was supplied by the various refineries who used different blends of crudes and processing methods to meet the Pennsylvania DOT specifications. This study was undertaken to catalog and evaluate the physical properties of AC-20 asphalt cements as supplied in 1973 by the various refineries. The fundamental and empirical consistency data have been evaluated and compared so that a specification based entirely on fundamental units of measurement can be developed in future. The test data have been made available to other researchers and agencies that are in the process of adopting viscosity graded asphalt cements. No attempt has been made to relate the physical properties of the asphalts to mix characteristics of pavement performance. Very good correlations were obtained between (a) log viscosity and log penetration at 77 F (25 C), (b) log viscosity and log penetration at 60 F (15.6 C), (c) viscosity at 77 and 60 F (25 and 15.6 C), (d) temperature susceptibility in 77 to 140 F (25 to 60 C) and 140 to 275 F (60 to 135 C) ranges, and (e) viscosity ratio at 77 and 60 F. Regardless of crude source, the satisfactory correlation obtained between shear susceptibility at 77 F and ductility at 60 F on thin film oven residues indicates that, in the specifications, shear susceptibility can be used in place of ductility requirement.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 56-64
  • Monograph Title: Asphalt properties and performance
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00128542
  • Record Type: Publication
  • ISBN: 0309023998
  • Files: TRIS, TRB
  • Created Date: May 14 1976 12:00AM