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

Abstract

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.