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Reaction of Hardened Portland Cement Paste With Carbon Dioxide

The effect of age, water-cement ratio, and evaporable-water content on the reaction of hardened cement paste with carbon dioxide was investigated, using small cylinders of cement paste. The rate and extent of the reaction are subject to manipulation by varying the evaporable water content of the pas...

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Detalles Bibliográficos
Autores principales: Hunt, Charles M., Tomes, Lewis A.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: [Gaithersburg, MD] : U.S. Dept. of Commerce, National Institute of Standards and Technology 1962
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5324964/
http://dx.doi.org/10.6028/jres.066A.048
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author Hunt, Charles M.
Tomes, Lewis A.
author_facet Hunt, Charles M.
Tomes, Lewis A.
author_sort Hunt, Charles M.
collection PubMed
description The effect of age, water-cement ratio, and evaporable-water content on the reaction of hardened cement paste with carbon dioxide was investigated, using small cylinders of cement paste. The rate and extent of the reaction are subject to manipulation by varying the evaporable water content of the paste. Pastes of different age and water-cement ratio tend to dry at different rates, and this difference exerts an important indirect effect on carbonation. Analysis of the specimens showed that less than one molecule of nonevaporable water was released for every molecule of carbon dioxide gained, except in paste of low water-cement ratio or at low levels of carbonation in other pastes. If calcium hydroxide were the only phase attacked, equimolecular CO(2)–H(2)O stoichiometry would be expected. The observed behavior does not rule out the possibility of some preferential attack on calcium hydroxide, but other phases can react while calcium hydroxide is still present. Water-cement ratio, particularly in very dense paste, may exert some effect on the comparative accessibility of different phases.
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spelling pubmed-53249642023-06-15 Reaction of Hardened Portland Cement Paste With Carbon Dioxide Hunt, Charles M. Tomes, Lewis A. J Res Natl Bur Stand A Phys Chem Article The effect of age, water-cement ratio, and evaporable-water content on the reaction of hardened cement paste with carbon dioxide was investigated, using small cylinders of cement paste. The rate and extent of the reaction are subject to manipulation by varying the evaporable water content of the paste. Pastes of different age and water-cement ratio tend to dry at different rates, and this difference exerts an important indirect effect on carbonation. Analysis of the specimens showed that less than one molecule of nonevaporable water was released for every molecule of carbon dioxide gained, except in paste of low water-cement ratio or at low levels of carbonation in other pastes. If calcium hydroxide were the only phase attacked, equimolecular CO(2)–H(2)O stoichiometry would be expected. The observed behavior does not rule out the possibility of some preferential attack on calcium hydroxide, but other phases can react while calcium hydroxide is still present. Water-cement ratio, particularly in very dense paste, may exert some effect on the comparative accessibility of different phases. [Gaithersburg, MD] : U.S. Dept. of Commerce, National Institute of Standards and Technology 1962 1962-12-01 /pmc/articles/PMC5324964/ http://dx.doi.org/10.6028/jres.066A.048 Text en https://creativecommons.org/publicdomain/zero/1.0/ The Journal of Research of the National Bureau of Standards Section A is a publication of the U.S. Government. The papers are in the public domain and are not subject to copyright in the United States. Articles from J Res may contain photographs or illustrations copyrighted by other commercial organizations or individuals that may not be used without obtaining prior approval from the holder of the copyright.
spellingShingle Article
Hunt, Charles M.
Tomes, Lewis A.
Reaction of Hardened Portland Cement Paste With Carbon Dioxide
title Reaction of Hardened Portland Cement Paste With Carbon Dioxide
title_full Reaction of Hardened Portland Cement Paste With Carbon Dioxide
title_fullStr Reaction of Hardened Portland Cement Paste With Carbon Dioxide
title_full_unstemmed Reaction of Hardened Portland Cement Paste With Carbon Dioxide
title_short Reaction of Hardened Portland Cement Paste With Carbon Dioxide
title_sort reaction of hardened portland cement paste with carbon dioxide
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5324964/
http://dx.doi.org/10.6028/jres.066A.048
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