Sustainable repairing and improvement of concrete properties using artificial bacterial consortium

Abstract

Bacillus flexus MK-FYT-3 and Bacillus haynesii MK-NW-9 were isolated, identified and used to construct a bacterial consortium that was able to heal small cracks of concrete and improve its properties. The results showed that the compressive and tensile strengths of bio-concrete significantly increased by (31.29, 36.3) (29, 39) % and less permeability with 21.1%, 23.1% after 7, 28 days respectively. Ultrasonic pulse velocity test was performed, and the bio-concrete gave higher values than control by 26% and 20% after 7, 28 days. In addition, surface healing of bio-concrete showed white precipitates around and inside the cracks after 7 days, which led to almost complete sealing of concrete after 28 days. The micro-analysis of bio-concrete using SEM and XRD showed crystalline precipitate with different shapes under SEM. We concluded that a bacterial consortium was able to repair and prevent the concrete cracks from spreading in addition to improving properties of concrete and that lead to increasing its life and sustainability.

Keywords:

• Sustainable repairing
• bacterial consortium
• cracks
• concrete
• Bacillus flexus
• Bacillus haynesii

Disclosure statement

No potential conflict of interest was reported by the authors.