Effect of accelerated carbonation on long-term water absorption behavior of cement-based materials
METADATA ONLY
Loading...
Author / Producer
Date
2025-02
Publication Type
Journal Article
ETH Bibliography
yes
Citations
Altmetric
METADATA ONLY
Data
Rights / License
Abstract
Concrete carbonation has been proven to be a potential path for reducing the carbon footprint of cement industry. However, since carbonation reaction significantly alters the chemical composition and microstructure of cement-based materials, it is necessary to carefully assess its effects on the transport properties and durability of concrete materials. The goal of this work is to clarify the effects of accelerated carbonation on both the pore structure and long-term water absorption behavior of cement-based materials using CEM II/B-M (T-LL) as the binder. Experimental results show that exposure to CO₂ at a concentration of over 65% for 90 days leads to substantial carbonation of Ca(OH)₂ and other calcium-bearing phases including C–S–H gels. Accelerated carbonation results in a refined pore structure of cement paste, marked by decreased porosity but increased specific surface area accessible to both N₂ and H₂O. The long-term capillary absorption of non-carbonated mortar observes the square root of time law in the initial stage and then markedly deviates down, which can be well captured by the modified Richards equation accounting for water sensitivity. In contrast, the long-term absorption into carbonated mortar consistently follows the square root of time law, which could be quantified using the conventional Richards equation. This suggests that after accelerated carbonation, the pore structure of cement mortar is less sensitive to water regain, potentially attributed to the changes in the nanostructure of C–S–H gels caused by carbonation. Additionally, carbonated mortar exhibits lower sorptivity and inherent permeability than non-carbonated mortar, indicating that accelerated carbonation decelerates the water transport in cement-based materials.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
58 (1)
Pages / Article No.
16
Publisher
Springer
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
Accelerated carbonation; Cement-based materials; Pore structure; Water absorption; Water permeability