Improving Soil Properties for Construction Usage with Fly Ash and Rice Husk Ash

Changes made to any soil property with the goal of improving the soil’s engineering performance are collectively referred to as soil improvement. This might include enhancing groundwater conditions, decreasing compressibility, minimising permeability, or strengthening the structure’s structural integrity. Soil enhancement might be a short-term solution to make building easier or a long-term strategy to improve the finished structure’s performance over time. Expansive soils, especially black cotton soil, pose serious problems for the building sector because of their negative swelling and shrinking characteristics. The purpose of this study is to better understand how stabilizing substances like fly ash and rice husk ash (RHA) might help address these issues and enhance the qualities of soil suitable for building. To evaluate the efficacy of RHA and fly ash as swell reduction layers and to improve unconfined compressive strength (UCS) in highway construction, the materials will be added to natural soil in different percentages (RHA: 0%, 15%, and 30%; fly ash: 10%, 20%, and 30%). Nine different combinations were tested using UCS after the quantities were established using the Taguchi optimization approach. The results suggest that adding these waste items can greatly strengthen the soil, and that certain combinations work best for stabilizing the soil. The study highlights how soils in construction can be addressed by utilizing sustainable resources like fly ash and RHA.