Assessment of potential resistance to moisture damage and fatigue cracks of asphalt mixture modified with ground granulated blast furnace slag

Fatigue and moisture damage have been recognized as the most prevalent problems on asphalt roads, necessitating large annual expenditures for road maintenance. Much industrial waste is added to bitumen paving to enhance its conventional quality while decreasing the negative impacts on the natural environment and increasing resistance to pavement distress. This research uses ground granulated blast furnace slag (GGBFS) to substitute conventional filler (Portland cement [PC]) in hot mix asphalt (HMA). To determine how the GGBFS affects the HMA's susceptibility to moisture and fatigue cracks, Marshall characteristics, tensile strength ratio (TSR), and index of retained strength (IRS) of the asphalt concrete were evaluated. HMA was prepared with different rates of GGBFS (0, 25, 50, 75, and 100%) instead of PC. The data support the usage of 50% GGBFS in asphalt pavements as a partial replacement of PC, which enhanced Marshal stability by 34.4%, reduced flow value by about 12.9%, and increased TSR and IRS by 11.1 and 14.54%, respectively. The fatigue resistance of the modified asphalt mix at the optimum rate was evaluated with the four-point bending beam test; the fatigue life (Nf) increased by 33.8% relative to the reference mixture. The results obtained from this research hold scientific value for researchers and method designers aiming to enhance the resistance of hot asphalt mixtures to moisture and cracking. Using waste materials as an alternative to PC contributes to cost reduction while mitigating the environmental damages associated with cement manufacturing. To summarize, this research highlights the significance of exploring sustainable options in the construction industry, emphasizing the importance of reducing costs, and minimizing environmental impacts.