Assessment of macroscopic properties of ecological building materials based on chemical microscopic phase composition and interface interaction mechanisms

Abstract This study investigates the macroscopic properties of ecological building materials prepared from recycled industrial waste through comprehensive analysis of chemical microscopic phase composition and interface interaction mechanisms. Three primary industrial wastes (fly ash, blast furnace slag, and steel slag) were systematically incorporated as cement replacements at various proportions. Advanced characterization techniques including X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry were employed to establish quantitative relationships between microstructural parameters and macroscopic performance. Results demonstrate that optimized waste incorporation achieves superior mechanical properties, with the optimal combination containing 15% fly ash, 7.5% steel slag, and 22.5% blast furnace slag exhibiting 52.3 MPa compressive strength, representing 16.2% improvement over reference cement. Quantitative phase analysis revealed enhanced C–S–H gel formation (58.2% vs. 54.3%) through pozzolanic reactions, while interfacial transition zone characteristics significantly influenced overall performance. The developed structure–property relationship models achieved correlation coefficients exceeding 0.92 for strength prediction, enabling rational material design optimization. This research provides scientific foundations for waste-derived building material development while contributing to circular economy implementation and environmental sustainability in construction industry.