TY - JOUR
T1 - A thermodynamic model for C-(N-)A-S-H gel: CNASH-ss. Derivation and validation
AU - Myers, R.J.
AU - Bernal, S.A.
AU - Provis, J.L.
PY - 2014/12/31
Y1 - 2014/12/31
N2 - The main reaction product in Ca-rich alkali-activated cements and hybrid Portland cement (PC)-based materials is a calcium (alkali) aluminosilicate hydrate (C-(N-)A-S-H) gel. Thermodynamic models without explicit definitions of structurally-incorporated Al species have been used in numerous past studies to describe this gel, but offer limited ability to simulate the chemistry of blended PC materials and alkali-activated cements. Here, a thermodynamic model for C-(N-)A-S-H gel is derived and parameterised to describe solubility data for the CaO–(Na2O,Al2O3)–SiO2–H2O systems and alkali-activated slag (AAS) cements, and chemical composition data for C-A-S-H gels. Simulated C-(N-)A-S-H gel densities and molar volumes are consistent with the corresponding values reported for AAS cements, meaning that the model can be used to describe chemical shrinkage in these materials. Therefore, this model can provide insight into the chemistry of AAS cements at advanced ages, which is important for understanding the long-term durability of these materials.
AB - The main reaction product in Ca-rich alkali-activated cements and hybrid Portland cement (PC)-based materials is a calcium (alkali) aluminosilicate hydrate (C-(N-)A-S-H) gel. Thermodynamic models without explicit definitions of structurally-incorporated Al species have been used in numerous past studies to describe this gel, but offer limited ability to simulate the chemistry of blended PC materials and alkali-activated cements. Here, a thermodynamic model for C-(N-)A-S-H gel is derived and parameterised to describe solubility data for the CaO–(Na2O,Al2O3)–SiO2–H2O systems and alkali-activated slag (AAS) cements, and chemical composition data for C-A-S-H gels. Simulated C-(N-)A-S-H gel densities and molar volumes are consistent with the corresponding values reported for AAS cements, meaning that the model can be used to describe chemical shrinkage in these materials. Therefore, this model can provide insight into the chemistry of AAS cements at advanced ages, which is important for understanding the long-term durability of these materials.
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84906318747&partnerID=MN8TOARS
U2 - 10.1016/j.cemconres.2014.07.005
DO - 10.1016/j.cemconres.2014.07.005
M3 - Article
SN - 0008-8846
VL - 66
SP - 27
EP - 47
JO - Cement and Concrete Research
JF - Cement and Concrete Research
ER -