Synergistic Utilization of Terracotta Tile Waste and Eucalyptus Tree Ash as Fine Aggregate Substitutes in Polymer-Modified Asphalt Mixtures

The growing demand for sustainable infrastructure and the urgent need to reduce environmental impact have led to the exploration of alternative materials in road construction. In this context, the current study investigates the partial replacement of fine aggregates, a major component of Hot Mix Asphalt (HMA), with industrial and agricultural waste materials to improve pavement performance while supporting eco-friendly practices. This research specifically focuses on the use of terracotta tile waste (TTW) and eucalyptus tree ash (ETA) as partial substitutes for fine aggregates, in combination with polymer-modified bitumen (PMB 40). Although earlier studies have suggested the potential of TTW and ETA individually, their combined application with PMB 40 in HMA mixtures has not been extensively examined. This study addresses that gap through a systematic experimental investigation. To improve pavement service life, three different HMA mixes were prepared using PMB 40 as the binder and DBM-II grade aggregates. Specimens were initially fabricated with varying binder contents (4, 4.5%, 5%, and 5.5%) to determine the optimum bitumen content and evaluate key performance parameters such as Marshall Stability, flow value, unit weight, air voids, voids filled with bitumen (VFB), and voids in mineral aggregates (VMA). The impacts of adding TTW and ETA at replacement levels of 5% and 10% for fine aggregates were then examined in relation to the control mix. The findings demonstrated that, while still meeting the requirements for roads with moderate traffic loads, a 10% substitution of TTW yielded the greatest Marshall Stability value of 34.88 kN, which was nearly three times greater than that of the control mix. Clinical Trial : Not Applicable