ABSTRACT
Fracture is a main degradation mechanism that Hot Mix Asphalt (HMA) materials endure during their service lives. Experimental tests, such as the Semi-Circular Bending test (SCB), use the ‘fracture energy’ to characterize the fracture resistance of these materials. This quantity is commonly computed as the ratio between the work required to fracture the mixture and the ligament area of the crack zone. Most standards assume that the ligament area corresponds to the simplified cross sectional rectangular area of the cracked specimen, ignoring the natural morphology of the crack zone induced by the heterogeneity of the microstructure of HMA materials. SCB tests were performed to quantify the fracture energy of an HMA after considering the actual ligament area of the fracture zone, as well as the variability related to this property. The results show that the actual morphology of the crack impacts the magnitude of the fracture energy of these mixtures.
