ABSTRACT
This study aims to improve the engineering properties of dune sand through sustainable stabilization using pozzolanic industrial and agricultural waste materials as partial replacements for cement. As per IRC SP:89 guidelines, Ordinary Portland Cement (OPC) is a preferred stabilizer due to its ability to initiate pozzolanic reactions, forming calcium silicate hydrate (C-S-H) gel that enhances soil strength. The selected pozzolanic materials—Wheat Straw Ash (WSA), Nano-Silica (NS), and Fluid Catalytic Cracking Catalyst Residue (FC3R)—are rich in reactive silica and alumina, contributing to enhanced pozzolanic activity while also reducing cement dependency. Their fine particle size and high specific surface area aid in pore filling and densification of the soil matrix. Stabilized specimens were prepared by partially replacing OPC with varying percentages of these additives. Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) tests were conducted on samples compacted at Maximum Dry Density (MDD), and the results were assessed against IRC specifications for subgrade applications.
