A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Hydration kinetics and microstructural development of a magnesium oxysulfate cement modified by macromolecules
https://orcid.org/0000-0001-6656-4288
https://orcid.org/0000-0001-7317-2661
https://orcid.org/0000-0003-1642-832X
Highlights Magnesium oxysulfate (MOS) cement was modified by macromolecules of vegetal origin. The effect of MgSO4 and macromolecules on hydration kinetics of MgO was studied. Both MgSO4 and macromolecules functioned as hydration retardants. Temperature during setting had decisive influence on final cement phase composition. Thermal properties of aggregates are important in the design of lightweight concrete.
Abstract Magnesium oxysulfates (MOS), obtained by hydration of MgO in MgSO4 solution, are highly interesting as binders in lightweight building materials due to their environmental sustainability and promising technological properties. Recent focus has been concentrated on tailoring the phase composition towards 5Mg(OH)2·MgSO4·7H2O (517 phase) by using various additives (e.g. citric acid) that generally act as retarders of the direct hydration of Mg(OH)2, a competing phase in this system. In this work, macromolecules of vegetal origin were investigated as possible retarders to promote the crystallization of the 517 phase. Isothermal and semi-adiabatic hydration experiments were performed, together with thorough microstructural investigations of hardened cements by electron microscopy techniques (SEM, TEM) as well as X-ray powder diffraction and quantitative phase analyses by Rietveld refinements. The results show a temperature and time dependent retardant effect that is only effective in promoting the crystallization of the 517 phase at ambient temperature. Implications for the manufacturing of lightweight concrete are discussed.
Hydration kinetics and microstructural development of a magnesium oxysulfate cement modified by macromolecules
https://orcid.org/0000-0001-6656-4288
https://orcid.org/0000-0001-7317-2661
https://orcid.org/0000-0003-1642-832X
Highlights Magnesium oxysulfate (MOS) cement was modified by macromolecules of vegetal origin. The effect of MgSO4 and macromolecules on hydration kinetics of MgO was studied. Both MgSO4 and macromolecules functioned as hydration retardants. Temperature during setting had decisive influence on final cement phase composition. Thermal properties of aggregates are important in the design of lightweight concrete.
Abstract Magnesium oxysulfates (MOS), obtained by hydration of MgO in MgSO4 solution, are highly interesting as binders in lightweight building materials due to their environmental sustainability and promising technological properties. Recent focus has been concentrated on tailoring the phase composition towards 5Mg(OH)2·MgSO4·7H2O (517 phase) by using various additives (e.g. citric acid) that generally act as retarders of the direct hydration of Mg(OH)2, a competing phase in this system. In this work, macromolecules of vegetal origin were investigated as possible retarders to promote the crystallization of the 517 phase. Isothermal and semi-adiabatic hydration experiments were performed, together with thorough microstructural investigations of hardened cements by electron microscopy techniques (SEM, TEM) as well as X-ray powder diffraction and quantitative phase analyses by Rietveld refinements. The results show a temperature and time dependent retardant effect that is only effective in promoting the crystallization of the 517 phase at ambient temperature. Implications for the manufacturing of lightweight concrete are discussed.
Hydration kinetics and microstructural development of a magnesium oxysulfate cement modified by macromolecules
https://orcid.org/0000-0001-6656-4288
https://orcid.org/0000-0001-7317-2661
https://orcid.org/0000-0003-1642-832X
Highlights Magnesium oxysulfate (MOS) cement was modified by macromolecules of vegetal origin. The effect of MgSO4 and macromolecules on hydration kinetics of MgO was studied. Both MgSO4 and macromolecules functioned as hydration retardants. Temperature during setting had decisive influence on final cement phase composition. Thermal properties of aggregates are important in the design of lightweight concrete.
Abstract Magnesium oxysulfates (MOS), obtained by hydration of MgO in MgSO4 solution, are highly interesting as binders in lightweight building materials due to their environmental sustainability and promising technological properties. Recent focus has been concentrated on tailoring the phase composition towards 5Mg(OH)2·MgSO4·7H2O (517 phase) by using various additives (e.g. citric acid) that generally act as retarders of the direct hydration of Mg(OH)2, a competing phase in this system. In this work, macromolecules of vegetal origin were investigated as possible retarders to promote the crystallization of the 517 phase. Isothermal and semi-adiabatic hydration experiments were performed, together with thorough microstructural investigations of hardened cements by electron microscopy techniques (SEM, TEM) as well as X-ray powder diffraction and quantitative phase analyses by Rietveld refinements. The results show a temperature and time dependent retardant effect that is only effective in promoting the crystallization of the 517 phase at ambient temperature. Implications for the manufacturing of lightweight concrete are discussed.
Hydration kinetics and microstructural development of a magnesium oxysulfate cement modified by macromolecules
Barbieri, Virginia (author) / Lassinantti Gualtieri, Magdalena (author) / Manfredini, Tiziano (author) / Siligardi, Cristina (author)
2020-02-28
Article (Journal)
Electronic Resource
English
Strength development in magnesium oxysulfate cement
| Elsevier | 1977
The hydration mechanism and performance of Modified magnesium oxysulfate cement by tartaric acid
| British Library Online Contents | 2017
The hydration mechanism and performance of Modified magnesium oxysulfate cement by tartaric acid
| Online Contents | 2017