Improving High-Performance Concrete (HPC) by integrating nano metakaolin and silica fume

The integration of nano metakaolin (NMK) and silica fume (SF) has demonstrated significant potential in enhancing the performance of High-Performance Concrete (HPC). This study investigates the effects of incorporating 15% silica fume with varying NMK contents (5%, 10%, and 15% by weight of cement) on the workability and compressive strength of HPC. Slump tests were conducted to assess workability, while compressive strength was measured at 3, 7, and 28 days. The results revealed a clear reduction in slump with increasing NMK content, attributed to the high surface area and water demand of NMK. Despite the reduced workability, compressive strength improved markedly, with the mix containing 10% NMK and 15% SF achieving the highest strength approximately 50% greater than the control at 28 days. However, strength gains slightly declined at 15% NMK, likely due to particle agglomeration and excessive water demand. The findings highlight the effectiveness of using a hybrid pozzolanic approach, with 10% NMK identified as the optimal dosage for maximizing strength while maintaining acceptable fresh-state properties