Bio-Mediated Self-Healing Concrete: Experimental Investigation for Sustainable Infrastructure Systems

Abstract

This is very important because there are a vast majority of construction material in infrastructure, and construction material is easily cracked by environmental stresses, shrinkage and mechanical loading. Such fissures enable the entry of water and chemicals that can enhance the corrosion of reinforced concrete and undermine structural stability. An approach to address this issue is a bacterial form of self-healing concrete, which repairs the cracks on its own and extends the longevity of concrete structure. This study investigates the experimental evaluation of a self-healing concrete containing Bacillus subtilis. Bacterial cultures and nutrients integrated into concrete were created and prepared. Conventional concrete was also made into control samples to allow comparisons. This included the casting of standard cube specimens (150 mm × 150 mm × 150 mm), at curing periods of 7, 14, and 28 days. Compressive strength tests of mechanical properties were performed and crack healing was checked through the formation of cracks artificially under moist conditions. Bacterial-infused concrete exhibited significantly better compressive strength than conventional samples during all curing intervals. In addition, crack closure found in bacterial specimens attributed to the generation of calcium carbonate from microbes was observed. The calcium mineralization process greatly alleviated the cracks and promoted the robustness of the concrete matrix. In this study, we demonstrate that bacteria-mediated self-healing concrete can function as a self-healing solution for fissures through superior mechanical properties and higher durability, providing an alternative for sustainable infrastructure construction through reduced maintenance needs.