Bacterial Self-Healing Concrete: Mechanisms, Incorporation Methods, and Future Perspectives — A Comprehensive Review

Abstract

Bio-concrete or self-healing concrete is an innovative concept concerning sustainable construction materials. Contrary to regular concrete prone to progressive deterioration due to the formation of cracks, specific types of alkali-tolerant bacteria, primarily Bacillus, make it possible for bio-concrete to produce CaCO₃ precipitation in emerging cracks so that autonomous restoration of integrity occurs through healing without any direct participation. The rising popularity of such biotechnology in the construction industry should be accounted for by its capacity to reduce the costs associated with maintenance and enhance the longevity of concrete structures. This literature review evaluates the evolution of the idea of bio-concrete starting from the theoretical background laid out in the early 1990s till today's application. The focus is on the principles of biomineralization, the process of production, and characteristics of dominant strains. Particular attention is drawn to advantages, in terms of enhanced compressive strength up to 40%, and limitations, including higher costs of production and challenges concerning bacteriology, of utilizing this type of concrete. At last, knowledge gaps in this sphere are indicated, and priorities in further research are set concerning the following issues: standardization, testing under extreme conditions, life cycle assessment, and applying machine learning.