Material Properties and Environmental Benefits of Hot-Mix Asphalt Mixes Including Local Crumb Rubber Obtained from Scrap Tires

This paper presents the results of a laboratory-based experimental investigation on properties asphalt binder and hot-mix (HMA) mixes modified by locally available crumb rubber, which was used as partial replacement weight. In this study, fine rubber with particle size in range 0.3–0.6 mm, obtained from scrap tires, added to through wet process. Crumb contents 5%, 10%, 15%, 19% weight were virgin order prepare samples, while unmodified control sample. The samples examined for measuring viscosity indirectly using penetration test, temperature resistance softening point test. Later, both binders produce HMA mixes. Two categories mix commonly Malaysia—namely, AC 14 (dense-graded) SMA (gap-graded)—were produced containing rubber. also produced, incorporating (0% rubber). All determine their volumetric properties, such bulk density, voids total (VTM), mineral aggregate (VMA), filled (VFA). addition, Marshall stability, flow, stiffness all determined. Test indicated that possessed higher than binder. increased increase content. content led improvements (bulk VTM, VMA, VFA) performance characteristics mixes—such stiffness—increased However, performed much better overall research findings suggest can be durable sustainable mixes, manifold environmental benefits, use flexible pavements carrying heavy traffic load highways.