Study of an Environmentally Friendly High-Performance Concrete (HPC) Manufactured with the Incorporation of a Blend of Micro-Nano Silica.

This study evaluates the influence of varying proportions of nano-silica (NS) and microsilica (MS) as partial substitutes for cement in the formulation of high-performance concrete (HPC). Mechanical assessments, including compression, tension, flexural strength, dynamic modulus, Poisson's ratio, and elasticity measurements, were performed at intervals of 3, 7, 28, 56, and 91 days to understand the impact on HPC's structural characteristics. Additionally, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-Ray spectroscopy (EDS) were carried out to examine changes in microstructure. Results indicate that incorporating 15% microsilica in the concrete mix yields a more pronounced improvement in mechanical properties compared to adding only 3% nano-silica, surpassing even the combination of 15% microsilica and 3% nano-silica. This substitution approach enhances sustainability by reducing cement usage.