Study on the feasibility of using waste glass in binder and asphalt mixture

In recent years, the amount of glass produced has increased due to improved living conditions and enhanced manufacturing processes. Unfortunately, a lot of used glass is not recycled; instead, it is thrown into the landfills, which leads to environmental issues. In this research, waste glass powder (WGP) is added to binder and asphalt mixture with various concentrations (0, 5, 10, 15, and 20%) by binder volume. Traditional binder tests are done, like penetration, ductility, softening point, flash and fire point, and specific gravity. Moreover, SuperPave performance grading (PG) tests are performed including rotational viscosity (RV), rolling thin-film oven (RTFO), pressure aging vessel (PAV), dynamic shear rheometer (DSR), and bending beam rheometer (BBR). Marshall stability/flow, dynamic creep, and fatigue (indirect tensile modulus test) are conducted on the modified asphalt mixture. There is an enhancement in penetration, softening point, flash and fire points, and unit weight values of the WGP-modified binder. The DSR test results present an enhancement in the rutting resistance of the modified binder due to an increase in the values of the rutting parameter as the WGP content increases. Also, the dynamic creep test reveals that the values of resilient modulus and creep stiffness improve as compared to traditional asphalt mixture. Moreover, as the WGP concentration increases, the accumulated strain and the permanent deformation values decrease in the dynamic creep test. Additionally, the fatigue test reveals an improvement in the resistance of fatigue cracking of the modified asphalt mixture by raising the resilient modulus values and decreasing the total horizontal recoverable deformation and this improves pavement life. In conclusion, adding (10–15%) of WGP to binder enhances the performance of pavement structures. WGP enhances the properties of binder and asphalt mixture, which are related and influenced by moderate to high temperatures. Moreover, adding WGP to binder and asphalt mixture as an alternative recycling method has critical environmental advantages.