Bacteria-induced internal carbonation of reactive magnesia cement

Xiao, X., Goh, L. X., Unluer, C. and Yang, E.-H. (2021) Bacteria-induced internal carbonation of reactive magnesia cement. Construction and Building Materials, 267, 121748. (doi: 10.1016/j.conbuildmat.2020.121748)

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Abstract

With lower calcination temperature, reactive magnesia cement (RMC) can be a potential alternative to the Portland cement. However, RMC concrete requires accelerated carbonation curing from external sources which greatly hinder the wider applications of RMC. This study proposed a bacteria-based method for the strength gain of RMC through internal carbonation. Sporosarcina pasteurii, urea, and yeast extract were used as a carbonation agent for internal carbonation of RMC pastes. Results showed that the flowability of the fresh bio-RMC paste increased by 20% while the initial setting time remained unchanged. Besides serving as the CO2 provider, urea can also function as superplasticizer to reduce the water demand of the bio-RMC pastes. The resulting bio-RMC pastes showed a continuous strength gain with time, demonstrating the feasibility of bacteria-induced internal carbonation of RMC. Microstructure analysis revealed abundant formation of hydrated magnesium carbonates in the bio-RMC pastes, which is responsible for the strength gain of the bio-RMC pastes.

Item Type:Articles
Additional Information:The authors acknowledge the financial support from the Singapore MOE Academic Research Fund Tier 2 (MOE2017-T2-1-087(S)).
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Unluer, Dr Cise
Creator Roles:
Unluer, C.Methodology, Resources, Supervision, Writing – review and editing
Authors: Xiao, X., Goh, L. X., Unluer, C., and Yang, E.-H.
College/School:College of Science and Engineering > School of Engineering > Infrastructure and Environment
Journal Name:Construction and Building Materials
Publisher:Elsevier
ISSN:0950-0618
ISSN (Online):1879-0526
Published Online:07 December 2020
Copyright Holders:Copyright © 2020 Elsevier
First Published:First published in Construction and Building Materials 267:121748
Publisher Policy:Reproduced in accordance with the copyright policy of the publisher

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