Carbon consuming concrete (CCC): A comprehensive study on mechanical properties and carbon uptake with electric arc furnace reduction slag

Abstract

This study executed a series of tests to validate and assess the mechanical characteristics, pore structures, and chemical components of carbon consuming concrete (CCC), which employs an electric arc furnace (EAF) slag to enhance carbon consumption. Mixing variables were categorized based on the cement replacement ratio of electric arc furnace reduction slag (ERS) powder and the use of nanobubble water, which captured carbon dioxide (CO₂). The mechanical performance was appraised through a compressive strength test, while the shrinkage behavior in a high-concentration CO₂ atmosphere was observed to compare autogenous, drying, and carbonation shrinkage. Matrix homogeneity was determined through mercury intrusion porosimetry (MIP) analysis. Energy-dispersive spectrometer (EDS) mapping, differential thermogravimetry (DTG), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were employed to examine the quantity of carbon fixation and the production of major components. The inclusion of ERS exhibited positive impacts on durability, such as increasing carbonation shrinkage resistance and reducing porosity in the long term. Concurrently, enhancements in compressive strengths were observed owing to the elevated formation of major components. Ultimately, it was established that the incorporation of ERS positively influences the amount of CO₂ consumption.