Comparison between natural and accelerated carbonation (3% CO 2 ): Impact on mineralogy, microstructure, water retention and cracking

Martin Auroy (1) , Stéphane Poyet (1) , Patrick Le Bescop (1) , Jean-Michel Torrenti (2) , Thibault Charpentier (3) , Mélanie Moskura (3) , Xavier Bourbon (4)

1 SECR - Service d'Etudes du Comportement des Radionucléides
2 IFSTTAR/MAST - Département Matériaux et Structures
3 LSDRM - Laboratoire Structure et Dynamique par Résonance Magnétique (LCF)
4 ANDRA - Agence Nationale pour la Gestion des Déchets Radioactifs

The consequences of accelerated carbonation at 3% CO2 were compared with those of natural carbonation (0.04%). Cement pastes (CEM I and CEM V/A) as well as the three major constitutive phases (C-S-H of different C/S ratios, portlandite and ettringite) were used and changes in the mineralogy, microstructure, water retention and cracking were investigated. The main conclusion was that accelerated carbonation at 3% CO2 was representative of natural carbonation although it promoted the precipitation of metastable calcium carbonate (aragonite and vaterite) in place of calcite. The results also showed that the presence of aragonite and vaterite were characteristic of the carbonation of ettringite and C-S-H respectively.

Domains: Material chemistry

Martin Auroy, Stéphane Poyet, Patrick Le Bescop, Jean-Michel Torrenti, Thibault Charpentier, et al.. Comparison between natural and accelerated carbonation (3% CO 2 ): Impact on mineralogy, microstructure, water retention and cracking. Cement and Concrete Research, 2018, 109, pp.64 - 80. ⟨10.1016/j.cemconres.2018.04.012⟩. ⟨cea-01771687⟩