Effects of the Type of Cement and the Concentration of CO₂ on the Carbonation Rate of Portland Mortars

Abstract:

The objective of this study was to examine the influences of the type of cement and the CO₂ concentration on the carbonation progress of cement materials. Thermogravimetric analysis were used to follow mineralogical changes of standard CEM I and CEM II mortars which were submitted to an accelerated carbonation at 20% and 50% CO₂, 20°C and 65% relative humidity. The results indicated that the carbonation of portlandite is complete in the case of CEM II mortar while there is a persistence of residual portlandite in the case of CEM I mortar. In other words, the carbonation rate of CEM I mortar is slower than the one of CEM II mortar, which is not only because of its greater content of portlandite but also because of the coverage of portlandite crystals by newly formed calcite. These results allow us to conclude that the carbonation rate of cement mortars depends especially on the type of cement while the CO₂ concentration does not affect it at all.

• Periodical: Applied Mechanics and Materials (Volumes 556-562)
• Pages: 965-968
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.556-562.965
• Online since: May 2014
• Authors: Son Tung Pham*, William Prince
• Keywords: Calcium Carbonate, Carbonation, Portlandite, Thermogravimetric Analysis

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