Micromechanical model for asphalt mixture coupling inter-particle effect and imperfect interface

•The linear spring model is adopted to simulate the asphalt mixture imperfect interface.•The imperfect interfacial bonding weakens the overall property of asphalt mixture.•The weaken effect of imperfect interface increase with inter-particle effect. Inter-particle effect and imperfect interface are the two major challenges during the micromechanical modeling of asphalt mixture due to its complex heterogeneity. This paper presents the development and validation of a micromechanical model regarding this concern. The linear spring model is adopted to simulate the imperfect interface between asphalt mortar and aggregates, and the replacement procedure is established to incorporate the imperfect interface effect into the Ju-Chen (J-C) model to coupling inter-particle effect and imperfect interface. The proposed model is used to predict the dynamic modulus of asphalt mixture and analyze the influence of inter-particle effect and imperfect interface. The results show that the predictions decrease with the interface parameter mr/mθ but increase with parameter Y(g). The imperfect interfacial bonding weakens the overall property of asphalt mixture and the weaken effect for composites with stronger inter-particle effect is more significant.