Investigation of the performance of hot mix asphalt modified with waste PVC

This study investigates the impact of waste polyvinyl chloride (PVC) modification on the performance of hot mix asphalt (HMA). Existing literature primarily focuses on the influence of PVC on different types of bitumen from the perspective of rheological improvements rather than mechanical performance. Moreover, the long-term behavior of PVC-modified asphalt remains largely unexplored, with a significant gap in understanding its fracture properties. This research aims to assess the effects of PVC on the viscoelastic and mechanical properties of asphalt mixtures, particularly in terms of rutting resistance, stiffness, and fracture behavior. To evaluate the mechanical response of PVC-modified asphalt mixtures, static and dynamic creep tests, indirect tensile stiffness modulus (ITSM) tests, and semi-circular bending (SCB) fracture tests were conducted. The experiments yielded results for tensile stiffness, creep stiffness, resilient modulus, creep stiffness modulus, fracture energy, fracture toughness, and flexibility index. While 1% PVC modification provided moderate improvements in rutting resistance and resilient modulus, higher PVC dosages generally increased stiffness and brittleness without significantly enhancing high-temperature rutting resistance. Overall, PVC modification does not offer substantial performance benefits in HMA, except for specific applications at intermediate temperatures, where 1% PVC appears to be the most effective dosage.