The effects of aging on the viscoelastic properties of cement asphalt composite mastic

This study aimed to investigate the effects of aging on the creep property and viscoelastic mechanical parameters of cement-asphalt composite binder. By combining the aging test and creep test of cement-asphalt composite binder with different material ratios, the effects of aging time and material ratio on the mechanical parameters of cement-asphalt composite binder were analyzed. An evolution equation on the viscoelastic mechanical parameters considering the influence of aging was established. On the basis of the fractional derivative model of three elements and four parameters, an aging factor of cement-asphalt composite binder was proposed, and an aging prediction model was established. Results show that the elastic components of cement-asphalt composite binder increased and the viscous components decreased when the aging extent deepened. The aging speed of cement-asphalt composite binder changed quickly in the initial stage of aging but slowed as the aging time elapsed. By properly increasing the consumption of asphalt, the material could maintain improved flexibility and deformability in the case of aging. The established aging factor could simultaneously reflect the effects of aging time and mix ratio on the viscoelastic properties of cement-asphalt composite binder.