<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Hydrated Portland cement paste exposed to a NaCl solution was acidified by adding HCl in small steps, gradually lowering the pH. The chloride binding of the cement paste changed as a function of the pH. For the range of pH from 13.2 to 12.2, decreasing pH resulted in a considerable increase in the chloride binding. At a pH of 11, the cement paste showed almost no chloride binding. In order to explain the changes in chloride binding upon lowering the pH, the phase assemblage was investigated with SEM-EDS, TGA and XRD and compared to a thermodynamic modelling.</p></abstract>

Hydrated Portland cement paste exposed to a NaCl solution was acidified by adding HCl in small steps, gradually lowering the pH. The chloride binding of the cement paste changed as a function of the pH. For the range of pH from 13.2 to 12.2, decreasing pH resulted in a considerable increase in the chloride binding. At a pH of 11, the cement paste showed almost no chloride binding. In order to explain the changes in chloride binding upon lowering the pH, the phase assemblage was investigated with SEM-EDS, TGA and XRD and compared to a thermodynamic modelling.

Towards the Understanding of the pH Dependency of the Chloride Binding of Portland Cement Pastes

Department of Materials Science and Engineering

Nordic Concrete Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Hydrated Portland cement paste exposed to a NaCl solution was acidified by adding HCl in small steps, gradually lowering the pH. The chloride binding of the...

Towards the Understanding of the pH Dependency of the Chloride Binding of Portland Cement Pastes

Published Online: Dec 01, 2018

Page range: 143 - 162

Received: Mar 15, 2018

Accepted: May 29, 2018

DOI: https://doi.org/10.2478/ncr-2018-0009

Keywords
chloride binding, pH, C-S-H, thermodynamic modelling, leaching

© 2018 Alisa Machner et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Towards the Understanding of the pH Dependency of the Chloride Binding of Portland Cement Pastes

Published Online: Dec 01, 2018

Page range: 143 - 162

Received: Mar 15, 2018

Accepted: May 29, 2018

DOI: https://doi.org/10.2478/ncr-2018-0009

Keywordschloride binding, pH, C-S-H, thermodynamic modelling, leaching

© 2018 Alisa Machner et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
chloride binding, pH, C-S-H, thermodynamic modelling, leaching