FATIGUE CRACK CHARACTERISTICS OF HMA MIXTURES CONTAINING RAP

This paper presents the preliminary findings of a laboratory study, in which the fatigue characteristics of hot-mix asphalt mixtures containing reclaimed asphalt pavement (RAP) were evaluated. A typical surface mixture commonly used in the state of Tennessee was evaluated at 0, 10, 20, and 30 percent of 4.75-mm sieve screened RAP content. Mixtures were subjected to long-term aging after being compacted. Fatigue characteristics of mixtures were evaluated through indirect tensile strength, semicircular bending (SCB) and semi-circular notched fracture resistance tests. Preliminary test results indicated that the inclusion of RAP generally increased the tensile strength and improved the mixture’s resistance to fracture failure for the mixtures in this study. However, mixture’s properties changed significantly when the RAP content increased to 30 percent.