Technological Approaches to Improve Early-Age Strength of Limestone Calcined Clay Cements

Limestone calcined clay cements (LC 3 ) present a sustainable alternative to traditional Portland cement due to their potential to significantly reduce CO 2 emissions. However, LC 3 cements often exhibit slower early-age strength development, which poses a challenge for their broader adoption. This study critically examines various technological approaches to enhance the early-age strength of LC 3 cements, focusing on physical, chemical, and hybrid methods. The findings highlight the effectiveness of increased clinker and supplementary cementitious material (SCM) fineness, chemical acceleration using calcium silicate hydrate (C-S-H) seeds and admixtures that promote the reaction of aluminate phases. Additionally, the study assesses the environmental impact of these strategies, evaluating their global warming potential (GWP) in relation to strength performance. The results demonstrate that while these methods effectively improve early-age strength, they may also inadvertently increase late-age strength, necessitating a balanced approach to optimize both performance and sustainability. This research provides a comprehensive framework for advancing LC 3 adoption in high early-age demand applications.