Experimental Investigation of the Engineering Properties of Stabilized Black Cotton Soil Using Industrial Waste Materials

In this study, the potential use of industrial waste materials, namely, copper slag (CS), iron ore tailings (IOT), and red mud (RM), as stabilizing agents for black cotton (BC) soil in pavement construction applications was evaluated. Laboratory tests were conducted to assess the performance of the stabilized BC soil, including Atterberg limits, compaction characteristics, California bearing ratio (CBR), unconfined compressive strength (UCS), permeability, and fatigue tests. Additionally, microstructural analysis was performed to further investigate the changes in the soil properties. The results indicated that BC soil mixed with CS, IOT, and RM exhibited enhanced plasticity, strength (UCS and CBR), permeability, and fatigue properties compared to untreated BC soil, regardless of the mix percentage. Notably, BC soil with 30% CS demonstrated comparable results to BC soil stabilized with 5% cement, significantly improving its properties. This study addressed a gap in pavement engineering research by evaluating the fatigue behavior of stabilized subgrade soils. It was concluded that incorporating 30% CS into BC soil not only enhanced its performance but also provided a sustainable alternative to traditional stabilizers such as cement and lime.