ABSTRACT
The primary pavement material used in airports in China is cement concrete, and to extend the pavement’s lifespan, an asphalt course is often overlaid on top of the original concrete slab after long-term service. However, new challenges occurred when reflect crack developed in the overlay. This study aims to evaluate one of crack repair methods, slotting repair, and optimize its parameters. the three-dimensional finite element model of overlaid pavement structure was modelled, in which Cohesive Zone Elements were placed at the interface between repair material and original asphalt overlay. Moreover, a crack was preset just under the overlay. The maximum stress around the crack tip and stress intensity factor were selected to the cracking trends and failure modes of the repair area, while the stiffness failure rate of cohesive elements and the number of concerned interface elements were chosen as the interfacial failure indexes. The results indicate that the crack is more likely to propagate in shear mode. The increase of the repair material modulus is beneficial to the interfacial bonding. And it is also recommended that the grooving depth not exceed 3cm.
