Influence of Bonding Condition of Different Interfaces on the Mechanical Responses and Failure Mode of Asphalt Pavement

In this study, a finite element model was established to compute the responses of asphalt pavement with various bonding conditions between the asphalt concrete layers (AC-AC interface) and between the asphalt concrete layer and base (AC-Base interface). The influence of bonding conditions of different interfaces on failure mode of asphalt pavement was discussed. The results indicated that poor bonding condition would increase longitudinal tensile strain at the bottom of the AC layers and vertical compressive strain at the top of subgrade, and the negative effects of two interfaces on pavement would enhance each other. It was observed that insufficient bonding strength would reduce the predicted life of pavement and, more importantly, debonding of AC-AC interface or two interfaces simultaneously would change pavement failure mode. Additionally, it should be noted that the fully-unbonded condition of AC-AC interface would affect the critical location for crack initiation in AC layers.