Abstract
This research investigates the biological and environmental advantages of using Bacillus subtilis in M20 grade concrete to improve its strength and longevity. Through the application of innovative analytical techniques, the study highlights the role of sustainable green building approaches in minimizing ecological impact while enhancing structural efficiency. It explores the advantages of bio-concrete, which utilizes microorganisms, in enhancing the durability and environmental sustainability of concrete structures. The objective is to assess the strength and durability characteristics of concrete containing varying concentrations of Bacillus subtilis and Bacillus sphaericus at levels of 106, 107, and 108 CFU/ml. The investigation compares the properties of bio-concrete with those of conventional concrete. It evaluates several long-term performance indicators, including compressive strength, water absorption, sorptivity, acid resistance (H2SO4 immersion), and chloride penetration over a period of 90 days. Results indicate that a concentration of 107 CFU/ml of Bacillus subtilis significantly enhances the durability and lifespan of the concrete. The self-repairing properties of bio-concrete, facilitated by the precipitation of calcium carbonate (CaCO3), are of significant importance, as imaging methods have validated its capacity to autonomously close cracks. This study highlights the advantages of integrating microorganisms into concrete, paving the way for the creation of environmentally friendly construction materials and practices that support sustainability goals. The findings underscore the potential of Bacillus subtilis as a sustainable solution for advancing green building practices, offering enhanced durability and reduced environmental impact in concrete applications.
Keywords: Bacillus Sphaericus, Bacillus Subtilis, Durability, Strength, Structural Efficiency, Sustainable Green Building.