Predicting the atmospheric carbonation of cementitious materials using fully coupled two-phase reactive transport modelling

Abstract

The durability assessment of cementitious materials and concrete subjected to atmospheric carbonation of concrete has been an extensive study of research. Experimental studies on the subject show, among other results, that the response depends strongly on the cement composition. This paper focuses on two model materials: an hydrated C 3 S paste and a low-pH paste, which exhibits a higher tendency to cracking. We show that a fully coupled reactive transport model can reproduce the measured experimental depths of carbonation without a need of fitting parameters. A sensitivity provides insights about the most relevant parameters to accurately model the atmospheric carbonation. Furthermore, results suggest that low-pH cement materials might be inherently less mechanically robust when subjected to atmospheric carbonation, due to a higher C-S-H decalcification rate. This implies that these materials are more likely to develop fractures, which could have implications in the framework of gas or radioactive waste disposal.

Use of Carbonated Water as Kneading in Mortars Made with Recycled Aggregates

“…XRD obtained for NA using normal and carbonated water as kneading water under CC are shown in Figure 6 . For normal water at 1 d, the main phases found were quartz (05-0490) [ 62 ], calcite (05-0586) [ 62 ], dolomite (11-0078), albite (10-0393) [ 85 ], and microline (19-0926) [ 84 ], which agrees with the fundamental composition of NA in Figure 2 . Hatrurite (86-0402) [ 62 ], larnite (33-0302) [ 62 ] from the cement used ( Figure 2 ), portlandite (44-1481) [ 62 ], and ettringite (37-1479) [ 62 ] from the reaction products of Ordinary Portland cement (OPC) [ 87 , 88 ] were also observed.…”

“…For NA mixtures, with 1 d and under CO 2 ·C, when using carbonated water in the kneading, compared with normal water, decreased the CS by 38.77% (NA-H 2 O-CO 2 ·C vs. NA-CO 2 ·H 2 O-CO 2 ·C). The low pH value of carbonated water along with accelerated carbonation (CO 2 ·C) results in a negative effect on strength [ 70 ] and delayed setting [ 71 ], which lowers the pH values of the mix [ 83 , 84 , 85 ]. For 3 d of curing, the effect of carbonated water on CS was still negative.…”

Assessment of the oxygen reactivity in a gas storage facility by multiphase reactive transport modeling of field data for air injection into a sandstone reservoir in the Paris Basin, France

“…HYTEC has been successfully demonstrated in various benchmark studies (Carrayrou et al, 2010) and various applications, e.g. cement degradation (Seigneur et al, 2020), in situ recovery (Lagneau et al, 2019;Collet et al, 2022), geological storage of radioactive waste (De Windt et al, 2014;De Windt and Spycher, 2019) and acid gases (Sin and Corvisier, 2019). The multiphase reactive transport coupling in HYTEC is managed using an operator-splitting approach that solves governing equations of flow, transport and chemistry in a sequential iterative manner.…”

Effects of the microstructural uncertainties on the poroelastic and the diffusive properties of mortar

“…The cement paste microstructure is estimated by a thermodynamical chemical model developed in (Socié et al 2021). This methodology is mainly used and validated in reactive transport (De Windt and Devillers 2010;Planel 2002;Seigneur et al 2020). The article focuses on the role of the microstructure uncertainties and the material properties on the analytical homogenization results.…”