Assessment of moisture susceptibility and stripping effect in wax based warm mix asphalt

This study investigates the utilization of two abundant local wastes, brick dust (BD) and rice husk ash (RHA), as fillers in warm asphalt mixtures to enhance moisture susceptibility and adhesion properties. Mechanical strength parameters including Marshall Stability (MS), Retained Marshall Stability (RMS), and Indirect Tensile Strength (ITS) were evaluated, along with stiffness assessed using modified Lottman test and refusal density values. Adhesion was measured using Cantabro loss and stripping resistance via boiling water test. The filler materials’ surface characteristics were analyzed using scanning electron microscopy (SEM). Results demonstrate significant improvements in mechanical properties upon the addition of filler materials, accompanied by reduced Cantabro loss and stripping values in filler-modified mixes. Optimal filler content replacement of up to 75% by weight of natural filler in asphalt mixes was identified. Statistical analysis revealed significant differences between the two filler types, highlighting BD as an active filler and RHA as a passive filler. In conclusion, BD and RHA represent promising alternatives for enhancing asphalt mixture performance, offering sustainable solutions for utilizing locally available wastes in infrastructure materials.