Mineralization dynamics of metakaolin-based alkali-activated cements

This paper investigates the early-age dynamics of mineral formation in metakaolin-based alkali-activated cements. The effects of silica availability and alkali content on mineral formation were investigated via X-ray diffraction and solid-state 29Si magic-angle spinning nuclear magnetic resonance sp...

Full description

Saved in:
Bibliographic Details
Published in:Cement and concrete research 2017-04, Vol.94, p.1-12
Main Authors: Gevaudan, Juan Pablo, Campbell, Kate M., Kane, Tyler J., Shoemaker, Richard K., Srubar, Wil V.
Format: Article
Language:English
Subjects:
B. Microstructure
B. X-ray diffraction
Bulk density
CEMENTS
Control systems
Correlation
D. Alkali-activated cement
D. Metakaolin
DENSITY
Dynamical systems
LIQUIDS
MATERIALS SCIENCE
Metakaolin
MINERALIZATION
NMR
NUCLEAR MAGNETIC RESONANCE
Physical properties
Porosity
Shrinkage
SILICA
SILICON 29
Silicon dioxide
Sodium
SODIUM SILICATES
X RADIATION
X-RAY DIFFRACTION
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This paper investigates the early-age dynamics of mineral formation in metakaolin-based alkali-activated cements. The effects of silica availability and alkali content on mineral formation were investigated via X-ray diffraction and solid-state 29Si magic-angle spinning nuclear magnetic resonance spectroscopy at 2, 7, 14, and 28days. Silica availability was controlled by using either liquid- (immediate) or solid-based (gradual) sodium silicate supplements. Mineral (zeolitic) and amorphous microstructural characteristics were correlated with observed changes in bulk physical properties, namely shrinkage, density, and porosity. Results demonstrate that, while alkali content controls the mineralization in immediately available silica systems, alkali content controls the silica availability in gradually available silica systems. Immediate silica availability generally leads to a more favorable mineral formation as demonstrated by correlated improvements in bulk physical properties.
ISSN:0008-8846
1873-3948
DOI:10.1016/j.cemconres.2017.01.001