This report describes a study comparing actual transverse cracking performance with that predicted by the Hajek-Haas method. No functional relationship was found to exist, and a limited laboratory study was conducted in an attempt to determine why. The study also considered the fact that transverse cracking in Michigan could have been essentially eliminated using McLeod's mix stiffness criteria; however, these criteria would exclude from use many stiff bituminous mixes which have given essentially crack-free service. Results indicated that the tensile strength, as well as stiffness modulus, both influence a bituminousmix's ability to resist cracking. Since stiffness modulus and tensile strength are not necessarily related, both should be included in models for predicting transverse cracking. Aggregate tensile strength also has a significant effect on the tensile strength of the mixes, thus mix tensile strength should not be estimated from asphalt cement properties alone. The data also indicate that bituminous stiffness can be lowered to such extent that tensile strength of the mix will no longer influence transverse cracking potential. It is thought that high tensile strength is required for stiff mixes to perform in an essentially crack-free manner. Though McLeod's guidelines will reject some stiffer mixes which can also display essentially crack-free performance, following his mix stiffness guidelines will essentially eliminate transverse cracking in Michigan. Procedures similar to those suggested by Burgess, et al, are suggested for identifying stiffer bituminous mixes that can perform essentially crack free. /Author/

  • Supplemental Notes:
    • This study was conducted in cooperation with DOT, Federal Highway Administration.
  • Corporate Authors:

    Michigan Department of State Highways & Transport

    Testing and Research Division
    Lansing, MI  United States  48904
  • Authors:
    • Novak Jr, E C
  • Publication Date: 1976-2

Media Info

  • Pagination: 32 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00149584
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-R-975 Final Rpt.
  • Contract Numbers: HP&R
  • Created Date: Apr 13 1977 12:00AM