Enhancing the Self-Maintenance Behavior of Asphalt Concrete through the Crack Healing Process

Because of the climate and the loss of the binder's volatiles, the asphalt cement binder typically ages throughout the course of its service life. The necessary flexibility, cohesiveness, and adherence to the aggregate's characteristics will be lost by the asphalt cement binder. Enhancement of the required properties may be gained by utilizing the self-maintenance property through crack healing process which can extend its useful service life. In this study, roller compaction was used to create slab samples of dense graded asphalt concrete.Slab samples were used to create beam specimens. Dynamic flexural stresses were used in controlled strain testing at 20°C in an environmental chamber until 50% of the stiffness was maintained.. The loading was applied through 0.1second followed by 0.9 second of rest periods. Changes in stiffness and deformation were used to track the accumulation of damage in the specimens. Beam specimens were stored for healing in an oven for two hours at 85° C, cooled to 20° C, then subjected to another cycle of load repetitions. The restored stiffness, deformation, and increase in fatigue life were used to calculate the crack healing rate. The reaction of a mixture during the loading and healing phases of laboratory experiments seemed to be significantly influenced by steric hardening. Increased fatigue life and recovered stiffness seem to be sufficient indicators of recovery. It was determined that, in comparison to the pre-healing situation, the percentage increase in fatigue life brought about by healing was 26%. Following healing, asphalt concrete's persistent distortion decreased by 0.4%. Following 100 repetitions, asphalt concrete's flexural stiffness improves by 5.2 times once it has healed. The flexural stiffness at failure increases by 5.02 folds after healing for asphalt concrete specimens.