Optimizing the Performance of Barite Concrete with Nano-Additives: A Sustainability Approach

Growing emphasis on sustainable construction practices has led to increased interest in incorporating alternative mineral-based materials into concrete formulations. Although barite powder is commonly known for its application in radiation shielding, its potential as a partial cement substitute remains largely unexplored due to uncertainties regarding its impact on hydration kinetics, ettringite stability, and long-term performance. This research investigates the combined effect of barite powder with Nano-Silica (NS) and Nano-Titania (NT) on enhancing both the mechanical behavior and internal structure of concrete. Barite was introduced as a partial cement replacement at dosage levels of 0%, 5%, 10%, 15%, and 20%, while NS and NT were consistently incorporated at 1% by weight of cement. Workability was evaluated using standard slump and compaction factor tests. Compressive and split tensile strengths were determined at curing ages of 7, 14, and 28 days. Microstructural evolution and hydration products were also characterized through Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX). The findings demonstrate that the incorporation of barite powder resulted in improved workability, with a 5% substitution leading to enhanced strength by promoting densification of the matrix and a reduction in porosity. Nevertheless, an increase in replacements resulted in a reduction of strength attributed to the formation of secondary ettringite. The optimal performance was observed at 5-15% barite with NS and NT, where improved microstructure and enhanced C-S-H gel formation were evident. Statistical validation using one-way ANOVA confirmed the significance of barite content combined with NS particles and curing age on mechanical performance. The combined use of nanomaterials and barite yielded superior strength and durability compared to their individual application.