Performance evaluation of warm mix asphalt using solid waste-derived fillers for sustainable pavement design

This study explores the sustainable application of industrial by-product fillers in Warm Mix Asphalt (WMA) production. Four types of waste-derived fillers—fly ash (F), jarosite (J), lime mud (L), and granulated slag (S)—were incorporated into WMA at different replacement levels. A comprehensive series of laboratory tests was carried out to assess the engineering behavior and environmental suitability of the developed mixes. Mixtures containing lime sludge and jarosite displayed superior performance against rutting and cracking, primarily due to their high porosity, fineness, large surface area, and rich content of calcareous minerals. Furthermore, a mechanistic–empirical design was undertaken for a two-lane, one-kilometer pavement section using the optimized mixes. The analysis indicated up to 40.8% savings in natural aggregates, a 34% reduction in binder requirement, and an equivalent 34.8% decrease in greenhouse gas emissions. The findings establish that waste-derived fillers not only improve WMA resistance to rutting, moisture damage, temperature variations, and aging but also serve as a sustainable alternative to natural fillers, contributing to resource conservation and environmental protection.