Akademik Veri Yönetim Sistemi
Düzce Üniversitesi Bilim ve Teknoloji Dergisi, cilt.13, sa.4, ss.1661-1675, 2025 (TRDizin)
This study investigates the influence of colemanite concentrator waste (CW) as a cement substitute on the gamma-ray shielding performance, mechanical, and physical properties of mortars. Mortar mixtures were prepared with varying CW proportions, and their consistency, setting time, compressive strength, pulse velocity, and water absorption were determined. Microstructural analysis using SEM and experimental gamma-ray (Cs-137-662 keV) shielding tests were also conducted. Results indicate that increasing CW substitution generally led to decreased compressive strength and increased total water absorption, consistency, and setting time. Notably, mixtures with CW content exceeding 5 wt% experienced disintegration during curing, primarily attributed to the significant retardation of cement hydration by boron compounds. For radiation shielding, despite the lower density of CW influencing overall bulk density, the presence of higher atomic number elements in colemanite demonstrated a positive contribution to gamma-ray attenuation. Specifically, at the lowest material thicknesses, the lead equivalent levels for CW2.5 and CW5 mortars were measured as 0.64 mmPb and 0.70 mmPb, respectively, revealing a clear radiation attenuation effect compared to the control. These findings highlight the potential of colemanite concentrator waste as a promising lead-free material for radiation shielding applications in cement-based composites.