X-ray microtomography of the carbonation front shape evolution of cement mortar and modeling of accelerated carbonation reaction

Abstract

In situ monitoring of the microstructure evolution of cement mortar in accelerated carbonation reaction for different carbonation ages was carried out by X-ray computed tomography (XCT). And the carbonation degrees of different time were measured by the volume fraction of uncarbonated and carbonated parts. Meanwhile, we presented a model for the carbonation of cement mortar by means of X-ray computed tomography (XCT). Based on the principles of chemical engineering processes, the reacted products become a solid inert ash layer. Finally, the model was validated with results of accelerated carbonation of cement mortar. The model is thus able to reasonably predict the carbonation phenomena for accelerated conditions.

Keywords

XCT / cement mortar / carbonation / in-situ monitoring / gray values / model / validation

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