Fracture Properties of High-Elasticity Asphalt Concrete Reinforced with Rubber Particles and Polyester Fibers

Semi-circular bending tests were conducted on high-elasticity asphalt concrete under different aging conditions to investigate the effects of rubber particles and polyester fiber contents on its fracture properties. Results showed that the incorporation of approximately 3% rubber particles increased the fracture energy by 15%, whereas the addition of 1.2% polyester fibers increased the fracture toughness and fracture energy by 4% and 19%, respectively. Aging-induced oxidative hardening enhanced the overall elastic modulus and interfacial constraint effect of the asphalt mixture, thereby improving the stress transfer efficiency among the rubber particles, polyester fibers, and the surrounding matrix. As a result, both the peak load and fracture toughness increased. However, compared with the unaged state, aged asphalt concrete became more susceptible to brittle fracture, with a decrease in fracture energy and a change in the crack propagation path from a curved to a straight trajectory.