Analysis and Comparison of Asphalt Mixes Containing Waste Fillers Using a Novel Ranking Methodology

This study compared the performance of asphalt concrete mixes containing five different wastes fillers [carbide lime (CL), copper tailings (CT), glass powder (GP), red mud (RM), and rice straw ash (RSA)] to a conventional mix containing stone dust (SD). The comparison was made using a novel ranking methodology, which is based on the various engineering properties of the asphalt mixes, and the priority assigned by the designer to each property. Various physical and chemical properties of the fillers were initially determined. Subsequently, the asphalt mixes were designed at their optimal binder contents and their stability, volumetric properties, cracking resistance, moisture susceptibility, rutting resistance, and active and passive adhesion were assessed based on various accepted standards. All mixes displayed satisfactory stability and volumetric properties, and the fillers having finer particles (RM, CT, CL, and GP) formed mixes with superior cracking and rutting resistance. Mixes containing calcium-based fillers (CL and SD) showed excellent adhesion and moisture resistance, while the GP mixes showed very poor moisture resistance. RM and RSA were determined as the best- and worst-performing fillers, respectively, based on the proposed ranking methodology.