Enhancing sustainability in construction: Exploring the self-healing mechanisms of bio-concrete

This study evaluates the self-healing efficiency of bio-concrete incorporating Bacillus megaterium (067) and Bacillus licheniformis (598), combined with Steel Fibre Reinforced Concrete (SFRC), for sustainable construction. Concrete specimens were prepared with bacterial concentrations of 103, 105, and 107 cells/ml, alongside steel fibre additions of 1%, 1.5%, and 2% by weight. Artificial cracks were introduced, and the healing performance was assessed through visual and microstructural analyses. Mechanical properties, including compressive, split tensile, and flexural strengths, were systematically tested. Results showed significant enhancements, with compressive strength improving by up to 18% and crack widths reducing by over 60% due to microbiologically induced calcite precipitation (MICP). Scanning Electron Microscopy (SEM) confirmed calcite deposition within cracks, validating bacterial involvement in self-healing. This research highlights the potential of integrating bacteria into SFRC to improve mechanical durability and self-healing, offering an innovative path toward eco-friendly and resilient construction materials.