Efficacy of Accelerated Carbonation Curing and Its Influence on the Strength Development of Concrete

The building sector is figuring out how to lower its embodied CO₂ in a sustainable way. The technology, known as Carbon Capture, Utilization, and Storage (CCUS), offers a possible remedy for this issue. Accelerated carbonation is one method of sequestering CO₂ in concrete. In this study, an M25 grade of concrete is made using Ordinary Portland Cement with 0–30% replacements of Class F fly ash. The specimens were exposed to accelerated carbonation curing for 6 h, 24 h, and 72 h, and then the specimens were tested for their compressive strength, carbonation depth, and pH. The CO₂ uptake was measured by Thermogravimetric analysis (TGA), and the occurrence of carbonation was confirmed using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results of the study indicate a significant improvement in the compressive strength with a percentage increase of 70.46%, 111.28%, 30.36%, and 36.69%, respectively, for 0%, 10%, 20%, and 30% fly ash contents in concrete samples subjected to 72 h of accelerated carbonation curing without affecting its alkalinity. The study reiterated that accelerated carbon curing is an advisable method for countries like India that are undergoing rapid economic developments.