Abstract
| Language | English |
|---|---|
| Number of pages | 8 |
| Journal | Green Materials |
| Issue number | 2049-1220 |
| Early online date | Jul 2018 |
| DOIs | |
| Status | E-pub ahead of print - Jul 2018 |
Cite this
Layered double hydroxides modify the reaction of sodium silicate-activated slag cements. / Ke, Xinyuan; Bernal, Susan A.; Provis, John L.
In: Green Materials, No. 2049-1220 , 07.2018.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Layered double hydroxides modify the reaction of sodium silicate-activated slag cements
AU - Ke, Xinyuan
AU - Bernal, Susan A.
AU - Provis, John L.
PY - 2018/7
Y1 - 2018/7
N2 - The impact of adding two types of layered double hydroxides (LDHs), commercial hydrotalcite (HT) and its thermally treated form (CLDH), on the reaction kinetics and phase assemblage development of a sodium silicate-activated slag cement was investigated. The reaction kinetics of LDH-modified cements was assessed by isothermal calorimetry, and the results were correlated with in situ attenuated total reflection Fourier transform infrared spectroscopy results collected over the first days of reaction, to identify the structural evolution of the main binding phase forming in these cements: a sodium-containing calcium aluminosilicate hydrate (C-(N)-A-S-H)-type gel. The addition of either HT or CLDH into sodium silicate-activated slag paste accelerates the precipitation of reaction products and increases the formation of HT in these cements, without causing significant changes to the C-(N)-A-S-H binding phase. This is extremely relevant in terms of the durability of alkali-activated slag cements, as a higher content of the HT-like phase has the potential to reduce their chloride permeability and enhance carbonation resistance.
AB - The impact of adding two types of layered double hydroxides (LDHs), commercial hydrotalcite (HT) and its thermally treated form (CLDH), on the reaction kinetics and phase assemblage development of a sodium silicate-activated slag cement was investigated. The reaction kinetics of LDH-modified cements was assessed by isothermal calorimetry, and the results were correlated with in situ attenuated total reflection Fourier transform infrared spectroscopy results collected over the first days of reaction, to identify the structural evolution of the main binding phase forming in these cements: a sodium-containing calcium aluminosilicate hydrate (C-(N)-A-S-H)-type gel. The addition of either HT or CLDH into sodium silicate-activated slag paste accelerates the precipitation of reaction products and increases the formation of HT in these cements, without causing significant changes to the C-(N)-A-S-H binding phase. This is extremely relevant in terms of the durability of alkali-activated slag cements, as a higher content of the HT-like phase has the potential to reduce their chloride permeability and enhance carbonation resistance.
U2 - 10.1680/jgrma.18.00024
DO - 10.1680/jgrma.18.00024
M3 - Article
JO - Green Materials
T2 - Green Materials
JF - Green Materials
SN - 2049-1220
IS - 2049-1220
ER -