Mini review

This mini review explores the development and performance of bacteria-based self-healing concrete and mortar, emphasizing the role of microorganisms such as Bacillus sphaericus and Bacillus subtilis in enhancing mechanical properties and promoting autonomous crack repair. The study examines the effects of bacterial concentration, curing conditions, and the incorporation of steel fibers and polyvinyl alcohol (PVA) fibers on the compressive, tensile, and flexural strengths of concrete. The primary self-healing mechanism is identified as microbially induced calcite precipitation (MICP), where bacterial activity facilitates calcium carbonate (CaCO₃) deposition to seal cracks. Advanced characterization techniques such as Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) confirm the formation of CaCO₃ and its impact on the material’s microstructure. The review highlights significant long-term strength improvements due to bacterial incorporation and presents bio-concrete as an eco-friendly alternative to conventional cement, contributing to sustainability by reducing the carbon footprint of construction materials. While the research demonstrates promising advancements, further studies are required to assess the long-term durability of microbial-treated materials under diverse environmental conditions and to evaluate the economic feasibility of large-scale implementation. This review underscores the potential of microbial intervention in advancing durable, self-healing, and sustainable concrete technologies.