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Title: Water chemical potential: A key parameter to determine the thermodynamic stability of some hydrated cement phases in concrete?

Abstract

The CaO-Al{sub 2}O{sub 3}-SO{sub 3}-H{sub 2}O system at 25 {sup o}C under 1 bar of pressure has been investigated with phase diagrams software (Zen + k) based on chemical potentials (or activities). The reported invariant points are similar to those obtained previously using equilibrium calculations. However Zen + k enables us to calculate systems at different relative humidities, and in conditions where water is not in excess, calcium monosulfoaluminate could be a stable phase and thus, as observed experimentally, remain for long times in an ordinary Portland cement paste.

Authors:
 [1];  [2];  [3]
  1. Department of Geotechnic and Material, Scetauroute - Egis group, Seyssins, 38180 (France)
  2. Department of Geochemistry, SPIN Division and UMR CNRS no. 6524, Ecole Nationale Superieure des Mines de Saint-Etienne (France)
  3. Civil Engineering Department, Ecole des Mines de Douai, Douai (France). E-mail: damidot@ensm-douai.fr
Publication Date:
OSTI Identifier:
20793285
Resource Type:
Journal Article
Resource Relation:
Journal Name: Cement and Concrete Research; Journal Volume: 36; Journal Issue: 5; Other Information: DOI: 10.1016/j.cemconres.2005.12.016; PII: S0008-8846(05)00338-8; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINATES; ALUMINIUM OXIDES; CALCIUM COMPOUNDS; CALCIUM OXIDES; COMPUTER CODES; CONCRETES; HUMIDITY; PHASE DIAGRAMS; PORTLAND CEMENT; STABILITY; SULFITES; WATER

Citation Formats

Albert, Blandine, Guy, Bernard, and Damidot, Denis. Water chemical potential: A key parameter to determine the thermodynamic stability of some hydrated cement phases in concrete?. United States: N. p., 2006. Web. doi:10.1016/J.CEMCONRES.2005.1.
Albert, Blandine, Guy, Bernard, & Damidot, Denis. Water chemical potential: A key parameter to determine the thermodynamic stability of some hydrated cement phases in concrete?. United States. doi:10.1016/J.CEMCONRES.2005.1.
Albert, Blandine, Guy, Bernard, and Damidot, Denis. Mon . "Water chemical potential: A key parameter to determine the thermodynamic stability of some hydrated cement phases in concrete?". United States. doi:10.1016/J.CEMCONRES.2005.1.
@article{osti_20793285,
title = {Water chemical potential: A key parameter to determine the thermodynamic stability of some hydrated cement phases in concrete?},
author = {Albert, Blandine and Guy, Bernard and Damidot, Denis},
abstractNote = {The CaO-Al{sub 2}O{sub 3}-SO{sub 3}-H{sub 2}O system at 25 {sup o}C under 1 bar of pressure has been investigated with phase diagrams software (Zen + k) based on chemical potentials (or activities). The reported invariant points are similar to those obtained previously using equilibrium calculations. However Zen + k enables us to calculate systems at different relative humidities, and in conditions where water is not in excess, calcium monosulfoaluminate could be a stable phase and thus, as observed experimentally, remain for long times in an ordinary Portland cement paste.},
doi = {10.1016/J.CEMCONRES.2005.1},
journal = {Cement and Concrete Research},
number = 5,
volume = 36,
place = {United States},
year = {Mon May 15 00:00:00 EDT 2006},
month = {Mon May 15 00:00:00 EDT 2006}
}
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