DEVELOPMENT OF EQUIPMENT AND TECHNIQUES FOR EVALUATING FATIGUE AND RUTTING CHARACTERISTICS OF ASPHALT CONCRETE MIXES

Fatigue and rutting characteristics are evaluated for a range of asphalt concrete base mixes. A rectangular beam on a rubber subgrade is used in the fatigue test. Tensile strain in the beam is measured by means of a strain gage bonded to the beam. Rutting characteristics are determined using both the Shell creep test and also a repeated load triaxial test. A temperature of 95 degrees F was used which is the mean pavement temperature for rutting a Georgia. The fatigue life of a mix was found to be primarily dependent upon the void and asphalt content of the mix. Fatigue life is inversely proportional to the air voids on a log-log plot with a small change in air voids having a large influence on fatigue life. For a long fatigue life the air void content should be between 2 and 4 or 5%. Going from an asphalt content of 4.5 to 4.75% approximately doubled the fatigue life. Other variables studied included mineral filler, asphalt cement viscosity, aggregate type and gradation, and 50 and 75 blow Marshall mixes. Rutting test indicated that moderate changes in mix variables do not greatly affect rutting.

• Supplemental Notes:
  • Prepared for the Georgia Department of Transportation in cooperation with the Department of Transportation, Federal Highway Administration.
• Corporate Authors:

  University of Georgia, Experiment

  Georgia Experiment Station
  Experiment, GA  United States 
• Authors:
  • Barksdale, R D
  • Miller II, J H
• Publication Date: 1977-6

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: 159 p.

Subject/Index Terms

• TRT Terms: Air voids; Asphalt concrete; Asphalt content; Asphalt mixtures; Creep tests; Fatigue (Mechanics); Fillers (Materials); Ruts (Pavements); Tension; Test procedures; Testing equipment; Triaxial shear tests
• Uncontrolled Terms: Fatigue life; Rut
• Old TRIS Terms: Air voids content
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00163544
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: GDOT Res Prj No 7305Final Rpt.
• Files: TRIS
• Created Date: Oct 29 1977 12:00AM