Fracture tests for bituminous-aggregate mixtures: Laboratory and field investigations

A major cause of premature pavement deterioration has been the cracking of the asphalt materials. This study investigates the ability to apply fracture mechanics principles to study asphalt concrete cracking through experimental techniques. Single-edge notched beam (SE(B)) and disk-shaped compact tension (DC(T)) test geometries were developed to estimate the fracture energy of asphalt concrete. Fracture energy can be measured from these laboratory tests with adequate accuracy, which allows for the application of numerical models to accurately predict asphalt concrete fracture behavior. The fracture behavior of asphalt concrete at low temperatures can be described as quasi-brittle and the fracture properties are specimen size dependent within the size range tested for this study (25 mm up to 450 mm). The DC(T) test was applied to forensic studies of pavement structures and fracture energy estimated from the tests provided an alternative parameter for describing the cracking potential of the asphalt concrete mixtures.