Effectiveness of Bacteria Based Self-healing Concrete for Enhanced Durability

The present experimental investigation focuses on examining the effectiveness of the use of a bacteria-based self-healing concrete admixture, reducing the maintenance burden on concrete structures. Introducing such innovative solutions can enhance durability, resulting in maintenance savings, reduced need for additional repair materials and thereby reducing embodied carbon. In the present research work, an experimental investigation was carried out on a self-healing admixture containing bacteria that produces spores that remain dormant until exposed to water and oxygen, activating them to produce limestone that fills the cracks automatically. The experimental tests were conducted to assess the self-healing efficiency (of both control specimens and counterparts containing the self-healing admixtures) by initially inducing cracks in notched cube samples. The samples were left to heal in an incubation chamber and then the crack healing efficiency was evaluated using permeability tests and photogrammetry-assisted visual assessments of crack width before and after self healing. Quality standards were followed in the preparation of bacterial concrete, including common laboratory tests such as sieve analysis, slump tests, compressive strength tests, and setting time evaluations in order to assess the material characteristics. The results show that the self-healing admixtures are effective in reducing the crack widths of the RC samples tested. The mechanical properties of the samples were also improved with an increase in compressive strength and its influence on setting time. The study concludes that bacteria based self-healing agents are an effective method to enhance the durability of RC structures. A particular innovation in the current is the addition of anticorrosion inhibitor, thereby enabling a resilient concrete mix that has the potential to close cracks automatically and protect the steel reinforcement from corrosion. The findings have practical implications, as the improved durability will result in reduced maintenance costs and increased service life.