Onset of cohesion in cement paste
(2004) In Langmuir 20(16). p.6702-6709- Abstract
- It is generally agreed that the cohesion of cement paste occurs through the formation of a network of nanoparticles of a calcium-silicate-hydrate ("C-S-H"). However, the mechanism by which these particles develop this cohesion has not been established. Here we propose a dielectric continuum model which includes all ionic interactions within a dispersion of C-S-H particles. It takes into account all co-ions and counterions explicitly (with pure Coulomb interactions between ions and between ions and the surfaces) and makes no further assumptions concerning their hydration or their interactions with the surface sites. At high surface charge densities, the model shows that the surface charge of C-S-H particles is overcompensated by Ca2+ ions,... (More)
- It is generally agreed that the cohesion of cement paste occurs through the formation of a network of nanoparticles of a calcium-silicate-hydrate ("C-S-H"). However, the mechanism by which these particles develop this cohesion has not been established. Here we propose a dielectric continuum model which includes all ionic interactions within a dispersion of C-S-H particles. It takes into account all co-ions and counterions explicitly (with pure Coulomb interactions between ions and between ions and the surfaces) and makes no further assumptions concerning their hydration or their interactions with the surface sites. At high surface charge densities, the model shows that the surface charge of C-S-H particles is overcompensated by Ca2+ ions, giving a reversal of the apparent particle charge. Also, at high surface charge densities, the model predicts that the correlations of ions located around neighboring particles causes an attraction between the particle surfaces. This attraction has a range of approximately 3 nm and a magnitude of 1 nN, values that are in good agreement with recent AFM experiments. These predictions are stable with respect to small changes in surface-surface separation, hydrated ion radius, and dielectric constant of the solution. The model also describes the effect of changes in cement composition through the introduction of other ions, either monovalent (Na) or multivalent (aluminum or iron hydroxide). (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/139617
- author
- Jönsson, Bo LU ; Wennerström, Håkan LU ; Nonat, A and Cabane, B
- organization
- publishing date
- 2004
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Langmuir
- volume
- 20
- issue
- 16
- pages
- 6702 - 6709
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000223066700030
- pmid:15274575
- scopus:4043111283
- pmid:15274575
- ISSN
- 0743-7463
- DOI
- 10.1021/la0498760
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Physical Chemistry 1 (S) (011001006), Theoretical Chemistry (S) (011001039)
- id
- 97daf0c9-e646-43ec-9ad8-63c64645c92c (old id 139617)
- date added to LUP
- 2016-04-01 12:12:08
- date last changed
- 2023-01-03 05:12:02
@article{97daf0c9-e646-43ec-9ad8-63c64645c92c,
abstract = {{It is generally agreed that the cohesion of cement paste occurs through the formation of a network of nanoparticles of a calcium-silicate-hydrate ("C-S-H"). However, the mechanism by which these particles develop this cohesion has not been established. Here we propose a dielectric continuum model which includes all ionic interactions within a dispersion of C-S-H particles. It takes into account all co-ions and counterions explicitly (with pure Coulomb interactions between ions and between ions and the surfaces) and makes no further assumptions concerning their hydration or their interactions with the surface sites. At high surface charge densities, the model shows that the surface charge of C-S-H particles is overcompensated by Ca2+ ions, giving a reversal of the apparent particle charge. Also, at high surface charge densities, the model predicts that the correlations of ions located around neighboring particles causes an attraction between the particle surfaces. This attraction has a range of approximately 3 nm and a magnitude of 1 nN, values that are in good agreement with recent AFM experiments. These predictions are stable with respect to small changes in surface-surface separation, hydrated ion radius, and dielectric constant of the solution. The model also describes the effect of changes in cement composition through the introduction of other ions, either monovalent (Na) or multivalent (aluminum or iron hydroxide).}},
author = {{Jönsson, Bo and Wennerström, Håkan and Nonat, A and Cabane, B}},
issn = {{0743-7463}},
language = {{eng}},
number = {{16}},
pages = {{6702--6709}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Langmuir}},
title = {{Onset of cohesion in cement paste}},
url = {{http://dx.doi.org/10.1021/la0498760}},
doi = {{10.1021/la0498760}},
volume = {{20}},
year = {{2004}},
}