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Logistic Model of Phase Transformation of Hardening Concrete

The objective of this study was to analyze the effects of the modification of cementitious materials with the admixture of a superplasticizer and mineral additive in the form of microsilica. We analyzed the hardening process of cementitious materials as an autocatalytic transformation from a viscous...

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Autores principales: Ślusarek, Jan, Nowoświat, Artur, Olechowska, Marcelina
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9267575/
https://www.ncbi.nlm.nih.gov/pubmed/35806528
http://dx.doi.org/10.3390/ma15134403
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author Ślusarek, Jan
Nowoświat, Artur
Olechowska, Marcelina
author_facet Ślusarek, Jan
Nowoświat, Artur
Olechowska, Marcelina
author_sort Ślusarek, Jan
collection PubMed
description The objective of this study was to analyze the effects of the modification of cementitious materials with the admixture of a superplasticizer and mineral additive in the form of microsilica. We analyzed the hardening process of cementitious materials as an autocatalytic transformation from a viscous liquid to a pseudo-solid body. The main achievement of the research involved the identification of changes in the content of the solid phase during the hardening of concrete mix as a model of the logistic curve. The phase transformation process begins with a viscous liquid which consists of water, cement, microsilica, superplasticizer and sand. The laboratory tests comprised research on the development of the kinetics of hardening heat of binder cement pastes and the development of mechanical properties of concrete in the hardening process. Three groups of mixtures with different concentrations of binders, determined by different water–binder indexes, were used. The first group was made up by cement paste consisting of cement and water. The second group contained cement paste from the first group supplemented with a superplasticizer, and the third group comprised the cement paste as in the second group, but additionally modified with microsilica. Using appropriate analyses, we defined a mathematical model of the phase transformation process. The model was then used for computer-aided numerical analyses. This made it possible to compare the relevant parameters of the logistic curve obtained for the seven different concrete mixes analyzed. Active impact of the applied mineral additive (microsilica) and that of chemical admixture in the form of a superplasticizer was demonstrated. All approximations of the measurement results with the use of a logistic curve had a determination level of over 0.98, indicating high agreement.
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spelling pubmed-92675752022-07-09 Logistic Model of Phase Transformation of Hardening Concrete Ślusarek, Jan Nowoświat, Artur Olechowska, Marcelina Materials (Basel) Article The objective of this study was to analyze the effects of the modification of cementitious materials with the admixture of a superplasticizer and mineral additive in the form of microsilica. We analyzed the hardening process of cementitious materials as an autocatalytic transformation from a viscous liquid to a pseudo-solid body. The main achievement of the research involved the identification of changes in the content of the solid phase during the hardening of concrete mix as a model of the logistic curve. The phase transformation process begins with a viscous liquid which consists of water, cement, microsilica, superplasticizer and sand. The laboratory tests comprised research on the development of the kinetics of hardening heat of binder cement pastes and the development of mechanical properties of concrete in the hardening process. Three groups of mixtures with different concentrations of binders, determined by different water–binder indexes, were used. The first group was made up by cement paste consisting of cement and water. The second group contained cement paste from the first group supplemented with a superplasticizer, and the third group comprised the cement paste as in the second group, but additionally modified with microsilica. Using appropriate analyses, we defined a mathematical model of the phase transformation process. The model was then used for computer-aided numerical analyses. This made it possible to compare the relevant parameters of the logistic curve obtained for the seven different concrete mixes analyzed. Active impact of the applied mineral additive (microsilica) and that of chemical admixture in the form of a superplasticizer was demonstrated. All approximations of the measurement results with the use of a logistic curve had a determination level of over 0.98, indicating high agreement. MDPI 2022-06-22 /pmc/articles/PMC9267575/ /pubmed/35806528 http://dx.doi.org/10.3390/ma15134403 Text en © 2022 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Ślusarek, Jan
Nowoświat, Artur
Olechowska, Marcelina
Logistic Model of Phase Transformation of Hardening Concrete
title Logistic Model of Phase Transformation of Hardening Concrete
title_full Logistic Model of Phase Transformation of Hardening Concrete
title_fullStr Logistic Model of Phase Transformation of Hardening Concrete
title_full_unstemmed Logistic Model of Phase Transformation of Hardening Concrete
title_short Logistic Model of Phase Transformation of Hardening Concrete
title_sort logistic model of phase transformation of hardening concrete
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9267575/
https://www.ncbi.nlm.nih.gov/pubmed/35806528
http://dx.doi.org/10.3390/ma15134403
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