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Title: Hydration and phase evolution of blended cement composites containing lithium and saturated metakaolin
Although the high efficiency of coupled lithium and saturated metakaolin in alkali-silica reaction mitigation has been documented, its influence on cement hydration remains uninvestigated. In this study, saturated metakaolin with varying degrees of saturation and its combined influence with lithium on the hydration kinetics, phase evolution, and development of microstructure and molecular structures of hydration products in the blended cement composite was investigated. The experimental and thermodynamic modeling results indicate the synergistic effect between saturated metakaolin and lithium in enhancing the hydration of cement, interaction between metakaolin and cement, incorporation of Al in the silicate chains, and precipitations of Al-rich phases. In the blended cement matrix, the dissolution of metakaolin, formation of calcium silicate hydrates with incorporated aluminum (C-(A)-S-H), and precipitation of strätlingite are improved by 19.6%, 17.6%, and 20.0%, respectively, and the formation of cubic siliceous hydrogarnet was triggered.  more » « less
Award ID(s):
1935799
PAR ID:
10482835
Author(s) / Creator(s):
;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Cement and Concrete Composites
Edition / Version:
144
Volume:
144
Issue:
C
ISSN:
0958-9465
Page Range / eLocation ID:
105268
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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