Effect of nano silica dosage on the performance and durability of high-performance concrete using experimental and AI-based modeling approaches

This study investigated the effect of varying nano silica content in optimized high-performance concrete, focusing on its influence on the hardened properties, microstructure, and challenges of particle agglomeration on strength and durability. Nano silica (NS) is very sensitive to the dosage and mixing procedure. Therefore, a superplasticizer with a high solid content was used to ensure proper dispersion of NS. NS is replaced at lower replacement ratios of 1%, 2% and 3% so that conventional mixing procedures are used and other costly special techniques should be avoided. An increased compressive strength with increased splitting tensile strength along with very low chloride permeability was observed for the nanomodified mixtures. The addition of 2% NS and 20% FA increased the 3-day and 28-day strengths from 24.80 MPa and 67.30 MPa to 40.90 MPa and 91.20 MPa, respectively. Hence, there are increases of 64.91% and 35.51% in the 3-day and 28-day strengths, respectively. In general, NS enhances the durability of HPC due to the reduction in pores because of its pozzolanic activity, nucleation effect, and filling effect. The developed XGBoost-based hybrid GUI was used for real-time compressive strength prediction, integrating experimental results with AI to design durable, efficient HPC mixtures for sustainable construction.