The paper "Multiscale investigation of ternary precursor proportioning in engineered geopolymer composites: Effects of silica fume replacement ratio and GGBS content" has been published in the journal Construction and Building Materials.
To reduce cement consumption and promote eco-friendly construction materials, engineered geopolymer composites (EGC) have been developed as sustainable alternatives to engineered cementitious composites (ECC). This study systematically investigates the effects of precursor tailoring, specifically silica fume (SF) replacement ratio (5–15 %) and ground granulated blast-furnace slag (GGBS) content (20–80 %), on the mechanical properties, microstructure, and sustainability of EGC. The results show that appropriate precursor composition enables a wide strength coverage, with compressive strengths ranging from 48 to 117 MPa, meeting the requirements of different structural applications. Digital image correlation (DIC) and in-situ crack analysis reveal stable multiple cracking behavior, with ultimate tensile strains consistently exceeding 8 % and effective crack width control within 120 μm. These findings confirm the achievement of multiple cracking and high tensile ductility through coordinated fibre/matrix interaction and tailored precursor design. Additionally, microstructural characterizations (XRD, FTIR, TGA) show that higher GGBS contents promote C-(N)-A-S-H gel formation and a degree of geopolymerization, leading to matrix densification and enhanced mechanical properties. Moderate SF replacement also contributes to pore filling, further increasing the matrix compactness. From a sustainability perspective, a cradle-to-gate life cycle assessment (LCA), using typical M45-ECC as a benchmark, shows that the developed EGC achieve approximately 50 % lower embodied carbon while maintaining comparable manufacturing feasibility. Overall, this study demonstrates that precursor-tailored EGC can simultaneously satisfy structural performance criteria and sustainability targets, highlighting their potential for low-carbon practical applications.
Note: Construction and Building Materials is a top journal in the field of engineering and technology in Q1, with an impact factor of 8.0 in 2025. The first author of the paper is doctoral student Wan Feihong, and Professor Guo Yutao is the corresponding author. The research results were funded by the Shenzhen Science and Technology Program and the National Natural Science Foundation of China.