4D Synchrotron X-ray Nanoimaging for Early Age Cement Curing: Where Are We and Where Should We Go?

The production of cement is a key indicator of a region’s level of development. As such, its use is essential for any society aiming to create healthy, comfortable, safe and secure living and working environments. However, these benefits come at a price; Portland cement production accounts for ≈8% of the total anthropogenic CO₂ emissions. If cement fabrication was considered a country, it would rank as the third largest emitter, after China and the United States. Consequently, reducing the CO₂ footprint of the construction industry is a societal need. Numerous low-carbon cement alternatives have been proposed, primarily involving the partial substitution of Portland clinker with materials that possess much lower CO₂ footprints. However, these cements have not been widely adopted because they exhibit reduced mechanical strength at 1 day of hydration, failing to meet current practices for formwork stripping. Therefore, a primary objective is to elucidate the mechanisms of early age cement hydration to accelerate their hydration rates.