Insights into nano-silica deposition for carbon textile/cement composite interfacial bond: Quantification of spatial features

Abstract

The bond-enhancing mechanisms of nano-silica (NS) deposition, described solely by a pozzolanic reaction, have often overlooked its underlying physicochemical nature. We propose a novel framework to quantify spatial disorder in NS deposition and to analyze its impact on the interfacial bond properties of carbon textiles in cement composite. The framework leverages domain knowledge (the morphological characteristics and topochemical hydration mechanisms of cement and NS particles) to estimate the degree of cohesive interconnection between the primary and secondary calcium silicate hydrate (C–S–H) phases precipitated in the textile/matrix interfacial transition zone (ITZ). Utilizing image analysis and rigorous statistical approaches, this framework quantifies latent spatial features derived from the size, polydispersity, and spatial heterogeneity of deposited NS particles. Results confirm that the textile/matrix interfacial bond is a macroscopic property governed not merely by the quantity of NS deposition but also by its topographical complexity, with scale dependence linked to the cement particle size distribution. Strong linear relationships in the inter-scale correlations (R² > 0.90 on average) demonstrate the consistency of our framework, significantly outperforming other quantitative methods.