Enhancing the rheology, reaction kinetics and early-age strength of limestone calcined clay cement (LC3) with sodium silicate addition

作者：Xiaodi Dai, Marcus Yio, Haoming Wu, Susan A. Bernal, Christopher Cheeseman, Hong S. Wong · 发表于：Cement and Concrete Research · 年份：2025 · DOI：10.1016/j.cemconres.2025.107997 · 被引用次数：35 · 研究领域：Concrete and Cement Materials Research、Innovative concrete reinforcement materials、Innovations in Concrete and Construction Materials

The effect of small-dose sodium silicate (SS) solutions with varying compositions on the rheology and early-age strength of limestone calcined clay cement (LC 3 ) was evaluated. SS addition reduced colloidal interactions in LC 3 , leading to significant reductions in initial yield stress and viscosity, depending on composition. All SS-added systems met the initial setting time requirements of EN 197–1. A solution containing 1 % Na 2 O and a silicate modulus of 0.4 notably accelerated silicate and aluminate reactions in cement clinker, as well as synergistic reactions between calcined clay and limestone. This resulted in 1-day strength gains of 120 % and 13 % compared to LC 3 and CEM I, respectively. Microstructural analysis revealed a denser matrix and refined pore structure at 1 day, consistent with accelerated phase evolution. These results demonstrate that well-formulated SS solutions can significantly enhance both rheology and early-age performance of LC 3 , supporting their use as effective accelerators in sustainable cement systems.