Evaluation of moisture-induced damage on the fatigue life of asphalt mixtures using failure tests of asphalt binders, interfaces, and mixtures

Fatigue cracking, a major distress in asphalt pavements, is worsened by traffic and climate conditions such as moisture effects on constituents and interfacial properties. However, investigation on fatigue's evolution in different scales under moisture effect is still scarce in the open literature. This work aims to assess moisture-induced damage effects on asphaltic materials focusing on the failure of asphalt binders, the aggregate-binder interface, and mixture. The methodology included tests under dry and wet conditions: linear amplitude sweep (LAS); asphalt bond strength (ABS) in different temperatures and pull rates for interfaces; indirect tensile strength (ITS), and tension-compression fatigue on asphalt mixtures. Key findings were: (i) moisture damage presents growing effects from binders to mixtures; (ii) LAS test results were not sensitive to moisture; (iii) ABS tests require proper field temperatures for accuracy; (iv) ITS ratio provide reliable conditioned fatigue expectations; and (v) fatigue testing without conditioning to hydrodynamic effects or real moisture susceptibility might overestimate service-life. Moisture damage presents growing effects from binders to mixtures; LAS results were not sensitive to moisture; ABS tests require proper field temperatures for accuracy; ITSR indicates conditioned fatigue behavior, unconditioned tests might overestimate service life.