Investigating the Potential of Iron Ore Tailing Waste as a Sand Replacement in Mortar and Its Effect on Mechanical Properties

Abstract

The depletion of natural sand resources due to excessive extraction has necessitated the exploration of sustainable alternatives. This study investigates the potential of iron ore tailings, a mining waste byproduct, as a partial replacement for sand in mortar production. Mortar samples were prepared with varying percentages (0%, 10%, 20%, and 30%) of iron ore tailings substituting natural sand. The workability, compressive strength, and ultrasonic pulse velocity were evaluated. The results demonstrated that incorporating iron ore tailings decreased the workability of fresh mortar due to the angular particle shape and porosity of the tailings. However, the compressive strength exhibited a significant increasing trend with higher tailing percentages, reaching a 70% increase at 30% replacement after 7 days compared to the control. Similarly, the ultrasonic pulse velocity, an indicator of concrete quality, gradually improved with increasing tailing content, suggesting reduced porosity due to the filling effect of the fine tailings particles. Linear regression analysis revealed a strong correlation between compressive strength and ultrasonic pulse velocity, confirming the potential of tailings to enhance mortar properties. The study concludes that iron ore tailings can serve as an effective sand replacement in mortar production, contributing to waste valorization and sustainable construction practices while preserving natural sand resources.