Bacteria-induced internal carbonation of reactive magnesia cement
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 metho...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2022
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/162315 |
| _version_ | 1826116955774386176 |
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| author | Xiao, Xi Goh, Li Xuan Unluer, Cise Yang, En-Hua |
| author2 | School of Civil and Environmental Engineering |
| author_facet | School of Civil and Environmental Engineering Xiao, Xi Goh, Li Xuan Unluer, Cise Yang, En-Hua |
| author_sort | Xiao, Xi |
| collection | NTU |
| description | 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. |
| first_indexed | 2024-10-01T04:19:53Z |
| format | Journal Article |
| id | ntu-10356/162315 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T04:19:53Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | ntu-10356/1623152022-10-13T04:55:02Z Bacteria-induced internal carbonation of reactive magnesia cement Xiao, Xi Goh, Li Xuan Unluer, Cise Yang, En-Hua School of Civil and Environmental Engineering Engineering::Civil engineering Bacteria Urea 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. Ministry of Education (MOE) The authors acknowledge the financial support from the Singapore MOE Academic Research Fund Tier 2 (MOE2017-T2-1-087 (S)). 2022-10-13T04:55:02Z 2022-10-13T04:55:02Z 2021 Journal Article Xiao, X., Goh, L. X., Unluer, C. & Yang, E. (2021). Bacteria-induced internal carbonation of reactive magnesia cement. Construction and Building Materials, 267, 121748-. https://dx.doi.org/10.1016/j.conbuildmat.2020.121748 0950-0618 https://hdl.handle.net/10356/162315 10.1016/j.conbuildmat.2020.121748 2-s2.0-85097581442 267 121748 en MOE2017-T2-1-087 Construction and Building Materials © 2020 Elsevier Ltd. All rights reserved. |
| spellingShingle | Engineering::Civil engineering Bacteria Urea Xiao, Xi Goh, Li Xuan Unluer, Cise Yang, En-Hua Bacteria-induced internal carbonation of reactive magnesia cement |
| title | Bacteria-induced internal carbonation of reactive magnesia cement |
| title_full | Bacteria-induced internal carbonation of reactive magnesia cement |
| title_fullStr | Bacteria-induced internal carbonation of reactive magnesia cement |
| title_full_unstemmed | Bacteria-induced internal carbonation of reactive magnesia cement |
| title_short | Bacteria-induced internal carbonation of reactive magnesia cement |
| title_sort | bacteria induced internal carbonation of reactive magnesia cement |
| topic | Engineering::Civil engineering Bacteria Urea |
| url | https://hdl.handle.net/10356/162315 |
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