Exploring a high-urease activity Bacillus cereus for self-healing concrete via induced CaCO3 precipitation

The structural integrity and esthetic appeal of concrete can be compromised by concrete cracks. Promise has been shown by microbe-induced calcium carbonate precipitation (MICP) as a solution for concrete cracking, with a focus on urease-producing microorganisms in research. Bacillus cereus was isolated from soil and employed for this purpose in this study due to its high urease activity. The strain exhibited strong tolerance for alkaline media and high salt levels, which grew at a pH of 13 and 4% salt concentration. The repair of concrete cracks with this strain was evaluated by assessing the effects of four different thickeners at varying concentrations. The most effective results were achieved with 10 g/L of sodium carboxymethyl cellulose (CMC-Na). The data showed that over 90% repair of cracks was achieved by this system with an initial water penetration time of 30 s. The study also assessed the quantity and sizes of crystals generated during the bacterial mineralization process over time to improve our understanding of the process.

Automated summary

In this study, Bacillus cereus was isolated from soil and used for repairing concrete cracks by evaluating the effects of four different thickeners at varying concentrations. The most effective result was achieved with 10 g/L of sodium carboxymethyl cellulose (CMC-Na). The study also assessed the quantity and sizes of crystals generated during the bacterial mineralization process to improve understanding of the process.