Strength performance and environmental assessment of Portland clinker

Alite influences both the early-age strength development and environmental footprint of concrete. However, the link between the alite content in clinker, strength development in concrete, and its carbon footprint remains overlooked in life cycle assessment. We study CEM I mortars containing clinkers with 5–85 wt% alite, combining thermodynamic modelling with a compressive strength prediction model based on the combined water fraction. Our model predicts that mortars made from high alite clinkers have 29% higher 28-day compressive strengths than that of low alite clinkers, at equivalent clinker and water contents. However, higher alite clinkers increase the CO 2 -eq. emissions of mortars by up to 19% compared with lower alite clinkers. In general, increasing alite content in clinker reduces CO 2 -eq. emissions per unit of strength gained in mortar. Therefore, the carbon footprint of concrete can be reduced by optimising both the alite content in clinker and concrete mix design.