Effect of gypsum on the early hydration of cubic and Na-doped orthorhombic tricalcium aluminate.
Author(s)
Type
Journal Article
Abstract
The tricalcium aluminate (C₃A) and sulfate content in cement influence the hydration chemistry, setting time and rheology of cement paste, mortar and concrete. Here, in situ experiments are performed to better understand the effect of gypsum on the early hydration of cubic (cub-)C₃A and Na-doped orthorhombic (orth-)C₃A. The isothermal calorimetry data show that the solid-phase assemblage produced by the hydration of C₃A is greatly modified as a function of its crystal structure type and gypsum content, the latter of which induces non-linear changes in the heat release rate. These data are consistent with the in situ X-ray diffraction results, which show that a higher gypsum content accelerates the consumption of orth-C₃A and the subsequent precipitation of ettringite, which is contrary to the cub-C₃A system where gypsum retarded the hydration rate. These in situ results provide new insight into the relationship between the chemistry and early-age properties of cub- and orth-C₃A hydration and corroborate the reported ex situ findings of these systems.
Date Issued
2018-04-07
Date Acceptance
2018-04-02
Citation
Materials (Basel, Switzerland), 2018, 11 (4)
ISSN
1996-1944
Publisher
MDPI
Journal / Book Title
Materials (Basel, Switzerland)
Volume
11
Issue
4
Copyright Statement
© 2018 by the authors. 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 (http://creativecommons.org/licenses/by/4.0/).
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).
License URL
Identifier
https://www.mdpi.com/1996-1944/11/4/568
Subjects
Science & Technology
Technology
Materials Science, Multidisciplinary
Materials Science
cubic tricalcium aluminate
orthorhombic tricalcium aluminate
gypsum
hydration
calorimetry
in situ XRD
CRYSTAL-STRUCTURE REFINEMENT
CLINKER COMPOUNDS HYDRATION
INITIAL HYDRATION
CALCIUM-SULFATE
SOLID-SOLUTION
C(3)A
SODIUM
SYSTEMS
PURE
LIGNOSULFONATE
calorimetry
cubic tricalcium aluminate
gypsum
hydration
in situ XRD
orthorhombic tricalcium aluminate
03 Chemical Sciences
09 Engineering
Publication Status
Published
Date Publish Online
2018-04-07