Fatigue Performance: Asphalt Binder versus Mixture versus Full-Scale Pavements

Abstract

The Federal Highway Administration (FHWA) built 12 asphalt pavements in 1993 to validate Superpave tests and specifications used to measure the rutting and fatigue cracking performances of hot-mix asphalts and asphalt binders. Each pavement had four test sites. These sites were tested for either rutting or fatigue cracking using the FHWA’s Accelerated Loading Facility (ALF). The main objective of the study documented in this paper was to compare the fatigue performance results from laboratory bending beam fatigue tests to the ALF fatigue cracking data obtained for these sites from lanes 1 through 4. The four lanes consisted of two asphalt pavement layer thicknesses (100 and 200 mm) and two asphalt binders (PG 58-34 and PG 64-22). Each lane was tested at three temperatures 10, 19, and 28°C. Another objective of this study was to investigate the relationship between the asphalt binder parameter for intermediate temperature performance (G*sinδ) and asphalt pavement fatigue life. Findings of this study showed that a relatively good correlation was obtained between the ALF pavement fatigue life and the asphalt mixture fatigue life from the strain-controlled bending beam fatigue tests. Comparison of the fatigue results at the three test temperatures showed rational trends with the longest fatigue life at 28°C and the shortest fatigue life at 10°C. Fatigue power models at these test temperatures were also obtained for asphalt mixtures produced using the two asphalt binders.