Effect of Accelerated Carbonation on the Performance of Concrete Containing Natural Zeolite

Abstract

An alternative carbonation technique was studied with normal concrete (NC) and concrete blended with natural zeolite (ZC) samples under an artificial environment with the help of carbonated-water curing. The effect of carbonated-water curing on concrete mixes incorporating natural zeolite powder as a partial replacement for cement was examined in this study. Accelerated carbonation was carried out by immersing concrete specimens in a 0.352-M sodium bicarbonate solution. The experimental program consisted of the evaluation of compressive strength, pH profiling, measurement of carbonation depth, X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and chemical composition measurements in order to study the extent of carbonation. ZC specimens cured in carbonated water had higher compressive strength development, greater extent of CaCO3 formation, and lower pH values than concrete cured in normal water for same curing period. Results obtained from XRD, TGA, FTIR, and chemical composition measurements showed that the amount of calcium carbonate increased in the carbonated concrete, which is closely associated with carbonation.