Microbial Self-Healing Concrete: A Sustainable Solution for Crack Repair

Concrete is the most commonly used material in the construction sector after water, with an annual production of approximately two tons per person worldwide. Crack formation is a significant issue in concrete structures, leading to reduced service life, increased repair costs, and increased maintenance. Although it is impossible to completely prevent cracks formation, various repair techniques have been developed. Traditional methods pose environmental and health risks. Consequently, there is a growing demand for sustainable solutions such as microbial self-healing techniques that have emerged as a promising alternative, offering rapid, autonomous crack repair while maintaining environmental compatibility. The self-healing effect of bacteria-based concrete acts as a self-sufficient repair mechanism, where bacterial cells initiate the healing process independently, without external monitoring or human intervention. This process is driven by bacterial metabolic activities that produce carbonate ions, which then interact with calcium ions present in the material, resulting in the formation of CaCO₃ crystals. This phenomenon, known as microbiologically or bacterially induced carbonate precipitation, plays a key role in enhancing the durability and longevity of concrete structures.