2644
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
4 CONCLUSION
The results showed that the carbonation significantly increased
the strength of MgO stabilised soil, and the UCS of highly
carbonated MgO stabilised soil was close to that of the 28-day
ambient cured PC-stabilised soil, which was ~10 times that of
28-day uncarbonated ambient cured MgO-stabilised soil. The
carbonation of MgO stabilised soil in the triaxial cell with high
CO
2
pressure happened much faster than in the incubator, the
former could be finished in a few hours while the latter took a
few days. Dissimilar to the uncarbonated ambient cured MgO-
or PC-stabilised soil, the UCS of highly carbonated MgO
stabilised soil did not increase with ambient curing period. The
XRD and SEM results indicated that nesquehonite, one of the
hydrated magnesium carbonates, was the main product of the
carbonated MgO in soil.
(a)
5 ACKNOWLEDGEMENTS
The experimental work presented in this paper was carried out
at the Geotechnical & Environmental Laboratory, Department
of Engineering, University of Cambridge, in the academic year
2009-2010 when the first author was a visiting researcher there.
The funding from CSC, NSSFC (51279032) and MOST
(2012BAJ01B02-01) of China is gratefully acknowledged. The
authors sincerely appreciate the French abstract translation by
Marine Deruelle.
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