Meso-scale finite element analysis on creep behaviour of asphalt mixture considering interface effect

This paper investigated the creep behaviour of asphalt mixtures using a randomly generated meso-scale finite element model that takes into account the effect of asphalt-aggregate interface. Simulation analysis on the three-point bending creep tests of asphalt mixture were performed and validated. Furthermore, parameters studies were conducted to evaluate the effect of gradation and angularity of coarse aggregate, air void content, and asphalt-aggregate interface strength. The results indicated that mesostructural parameters and interface properties have an important effect on the creep behaviour of asphalt mixture. The creep performance of medium-sized asphalt mixture is better than that of fine-sized asphalt mixtures. The larger the angularity index of coarse aggregate is, the better ability asphalt mixture has to resist deformation. As to the suspended dense structure asphalt mixtures, with the increase of void ratio, the creep deformation increase gradually, and the excessive void ratio would lead to the fracture of the interface. Asphalt-aggregate interface with higher interface strength would result in better resistance to of the mixture to permanent deformation.