Effects of interface conditions on reflective cracking development in hot-mix asphalt overlays

A three-dimensional finite element model was developed to Investigate the fracture behavior of a hot-mix asphalt (HMA) overlay on a jointed concrete pavement (JCP). Moving vehicular loads were applied to the HMA overlay on top of a joint to develop reflective cracking. A bilinear cohesive zone model (CZM) was inserted in the HMA overlay right over the joint. An interface constitutive model was implemented to specify interfacial behaviors between HMA-concrete layers. This study primarily examined the effects of interface bonding conditions on reflective cracking. The local and global behaviors of reflective cracking were investigated under various interface conditions regarding interfacial stiffness and bonding strength. Reflective cracking potential is quantified with representative fracture area (RFA), which represents a fractured area in the cross section of the HMA overlay. As a result, the fractured area increases significantly as the interface bonding strength becomes lower. On the contrary, the fractured area decreases slightly as the interface stiffness becomes lower.