Evaluation of Biochemical Reaction Effects in Bacterial Concrete

ABSTRACT This study explores the mechanical properties and self‐healing capabilities of bacterial concrete using Bacillus species in M25 grade concrete. Various bacterial concentrations 0%, 5%, 10%, and 15% were incorporated to assess their influence on compressive, flexural, and split tensile strengths, as well as crack‐healing behavior. The selected bacteria were capable of inducing microbial calcium carbonate precipitation (MICP), promoting internal crack sealing. Strength tests and self‐healing evaluations were conducted over a 28‐day period. The results indicated that a 10% bacterial concentration yielded the most effective performance, with a 20%–30% increase in strength compared to control specimens. Crack closure efficiency reached up to 23.80% due to visible microcrack sealing. However, concentrations above 10% showed diminished returns, suggesting a saturation point beyond which bacterial effectiveness declines. Microstructural analyses using Scanning Electron Microscopy (SEM) and X‐Ray Diffraction (XRD) confirmed the formation of CaCO 3 within the concrete matrix. Overall, the findings support bacterial concrete as a promising, sustainable solution for improving structural durability and minimizing maintenance.