TY - JOUR
T1 - Properties of well cement following carbonated brine exposure under HTHP conditions
T2 - a comparative study of alkali-activated and class G cements
AU - Samarakoon, M. H.
AU - Ranjith, P. G.
AU - Wanniarachchi, W. A.M.
N1 - Funding Information:
The authors acknowledge the financial support received from the Monash University Postgraduate Publication Award and ARC Linkage grant (Grant ID: LP150100103 ). The authors express thanks to Independent Cement & Lime Pty Ltd, Australia and Adelaide Brighton Cement Ltd, Australia, for providing the materials used in this study. The authors would also like to acknowledge the use of the facilities of the Monash X-ray Platform, the Monash Analytical Platform and the Monash Centre for Electron Microscopy – a Node of Microscopy Australia.
Funding Information:
The authors acknowledge the financial support received from the Monash University Postgraduate Publication Award and ARC Linkage grant (Grant ID: LP150100103). The authors express thanks to Independent Cement & Lime Pty Ltd, Australia and Adelaide Brighton Cement Ltd, Australia, for providing the materials used in this study. The authors would also like to acknowledge the use of the facilities of the Monash X-ray Platform, the Monash Analytical Platform and the Monash Centre for Electron Microscopy ? a Node of Microscopy Australia.
Publisher Copyright:
© 2021
PY - 2022/2
Y1 - 2022/2
N2 - Carbonation of cement under high temperature and high pressure (HTHP) subsurface conditions is a significant concern with typical underground wells. This study evaluates the carbonation-induced properties and mechanisms of low to high calcium-based alkali-activated cement (AAC) compared with class G cement (GC). Cement systems exposed to carbonated brine for 28 days were experimentally characterised using chemical, mechanical, and microstructural tests. Alkalinity testing indicated a noticeable pH change due to carbonation of GC with a greater release of calcium into the leaching solution, whereas sodium and magnesium leaching were dominant for AACs. Increasing the amount of calcium in AACs via slag increases the extent of carbonation, which improves the mechanical properties, resulting in a dense microstructure. Principal mechanisms of carbonation are suggested based on the chemical, mineral and microstructural characteristics of carbonated cement. AACs have a different mechanism, resulting in complete carbonation compared with the well-defined carbonated zone at the sample surface of GC.
AB - Carbonation of cement under high temperature and high pressure (HTHP) subsurface conditions is a significant concern with typical underground wells. This study evaluates the carbonation-induced properties and mechanisms of low to high calcium-based alkali-activated cement (AAC) compared with class G cement (GC). Cement systems exposed to carbonated brine for 28 days were experimentally characterised using chemical, mechanical, and microstructural tests. Alkalinity testing indicated a noticeable pH change due to carbonation of GC with a greater release of calcium into the leaching solution, whereas sodium and magnesium leaching were dominant for AACs. Increasing the amount of calcium in AACs via slag increases the extent of carbonation, which improves the mechanical properties, resulting in a dense microstructure. Principal mechanisms of carbonation are suggested based on the chemical, mineral and microstructural characteristics of carbonated cement. AACs have a different mechanism, resulting in complete carbonation compared with the well-defined carbonated zone at the sample surface of GC.
KW - Alkali-activated cement
KW - CaCO
KW - Carbonation mechanisms
KW - Class G cement
KW - HTHP conditions
UR - http://www.scopus.com/inward/record.url?scp=85120417325&partnerID=8YFLogxK
U2 - 10.1016/j.cemconcomp.2021.104342
DO - 10.1016/j.cemconcomp.2021.104342
M3 - Article
AN - SCOPUS:85120417325
SN - 0958-9465
VL - 126
JO - Cement and Concrete Composites
JF - Cement and Concrete Composites
M1 - 104342
ER -