Myers, R.J., L'Hôpital, E., Provis, J.L. et al. (1 more author) (2015) Composition-solubility-structure relationships in calcium (alkali) aluminosilicate hydrate (C-(N,K-)A-S-H). Dalton Transactions, 44 (30). 13530 - 13544. ISSN 1477-9226
Abstract
The interplay between the solubility, structure and chemical composition of calcium (alkali) aluminosilicate hydrate (C-(N,K-)A-S-H) equilibrated at 50 °C is investigated in this paper. The tobermorite-like C-(N,K-)A-S-H products are more crystalline in the presence of alkalis, and generally have larger basal spacings at lower Ca/Si ratios. Both Na and K are incorporated into the interlayer space of the C-(N,K-)A-S-H phases, with more alkali uptake observed at higher alkali and lower Ca content. No relationship between Al and alkali uptake is identified at the Al concentrations investigated (Al/Si ≤ 0.1). More stable C-(N,K-)A-S-H is formed at higher alkali content, but this factor is only significant in some samples with Ca/Si ratios ≤1. Shorter chain lengths are formed at higher alkali and Ca content, and cross-linking between (alumino)silicate chains in the tobermorite-like structure is greatly promoted by increasing alkali and Al concentrations. The calculated solubility products do not depend greatly on the mean chain length in C-(N,K-)A-S-H at a constant Ca/(Al + Si) ratio, or the Al/Si ratio in C-(N,K-)A-S-H. These results are important for understanding the chemical stability of C-(N,K-)A-S-H, which is a key phase formed in the majority of cements and concretes used worldwide.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Royal Society of Chemistry 2015. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 19 Nov 2015 18:44 |
Last Modified: | 19 Nov 2015 18:44 |
Published Version: | https://dx.doi.org/10.1039/c5dt01124h |
Status: | Published |
Publisher: | Royal Society of Chemistry |
Refereed: | Yes |
Identification Number: | 10.1039/c5dt01124h |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:90502 |