Optimum concentration of Bacillus megaterium for strengthening structural concrete

• Main Authors: Andalib, R., Abd. Majid, M. Z., Hussin, M. W., Ponraj, M., Keyvanfar, A., Mirza, J., Lee, H. S.
• Format: Article
• Published: Elsevier Ltd 2016
• Subjects: TA Engineering (General). Civil engineering (General)
• Online Access: http://eprints.utm.my/id/eprint/72198/; https://www.scopus.com/inward/record.uri?eid=2-s2.0-84966738310&doi=10.1016%2fj.conbuildmat.2016.04.142&partnerID=40&md5=4e0c3e7c78845b1c00c7b00bd12d673c
• Institution: Universiti Teknologi Malaysia

Five different cell concentrations of Bacillus megaterium (10 × 105 to 50 × 105 cfu/ml) were introduced in structural concrete to achieve the optimum concentration of bacteria. The significant increase in the strength was obtained in the case of 30 × 105 cfu/ml at different ages. The strength of highest grade of bacterial concrete had improved (24%) as compared to lowest grade (12.8%) due to calcification mechanism. Microbial calcite precipitation was quantified using X-ray diffraction analysis, visualized by scanning electron microscopy and analyzed by energy dispersive spectrometer. It was found that the optimum concentration of B. megaterium had a positive effect on high strength structural concrete.