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Sandy Soil Improvement through Microbially Induced Calcite Precipitation (MICP) by Immersion
Published on: September 12, 2019
Calcite-forming bacteria for compressive strength improvement in mortar
Sung-Jin Park1, Yu-Mi Park, Woo-Young Chun
1Department of Microbiology, Kyungpook National University, Daegu 702-701, Korea.
Journal of Microbiology and Biotechnology
|May 15, 2010
Summary
Researchers identified new calcite-forming bacteria (CFB) to enhance concrete mortar strength. Arthrobacter crystallopoietes KNUC403 demonstrated the most significant improvement in compressive strength, showcasing potential for sustainable construction materials.
Area of Science:
- Microbiology
- Materials Science
- Civil Engineering
Background:
- Microbiological calcium carbonate precipitation (MCP) is explored for enhancing concrete mortar compressive strength.
- Limited research exists on utilizing calcite-forming bacteria (CFB) for this purpose.
Purpose of the Study:
- To discover and characterize novel CFB capable of improving concrete mortar compressive strength.
- To evaluate the efficacy of isolated CFB in enhancing the mechanical properties of concrete.
Main Methods:
- Isolation of four CFB from environmental concrete structures.
- Identification of CFB using 16S rRNA gene sequence analysis (Sporosarcina soli KNUC401, Bacillus massiliensis KNUC402, Arthrobacter crystallopoietes KNUC403, Lysinibacillus fusiformis KNUC404).
- Characterization of CaCO3 crystal formation using stereomicroscopy, scanning electron microscopy, and X-ray diffraction.
Main Results:
- Four CFB genera were successfully isolated and identified.
- Bacterial colonies exhibited apparent crystal aggregates.
- CaCO3 crystal growth and structure were confirmed.
- Concrete mortar cubes treated with CFB showed improved compressive strength, with KNUC403 yielding the best results.
Conclusions:
- Novel CFB, including Arthrobacter crystallopoietes KNUC403, can significantly enhance concrete mortar compressive strength.
- MCP using specific bacterial strains offers a promising avenue for developing stronger and potentially more sustainable construction materials.
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