INVESTIGATING THE IMPACT OF BACILLUS CEREUS INDUCED SELF HEALING ON THE COMPRESSIVE STRENGTH OF CONCRETE

Concrete is susceptibility to cracking, this compromises its structural integrity and durability, necessitating innovative approaches for repair and maintenance. This research investigates the effectiveness of Bacillus cereus in enhancing the self-healing properties of concrete and its impact on compressive strength. The study explores the physical properties, mechanical properties, biological self-healing mechanism where Bacillus cereus facilitates calcium carbonate precipitation within cracks, impacting bacillus cereus induced self-healing on the compressive strength of concrete. Concrete cubes were subjected to experimental procedures including sieve analysis, slump, compacting factor, mechanical test such as concrete crushing and impact value, X-ray diffraction analysis (XRD). Concrete cubes were produced using a water-cement ratio of 0.50, with Bacillus cereus of two species B1 and B2 with concentration of 1 × 108 CFU and 5 × 108 CFU respectively, incorporated as the biological healing agent. The specimens were subjected to curing periods of 7, 14, 21, and 28 days, and their compressive strength was determined in accordance with BS EN 12390-3 standards. Results indicated that the inclusion of Bacillus cereus improved the self-healing efficiency of concrete 77% and 84% for B1 and B2 respectively, particularly in sealing microcracks. The compressive strength when compared to conventional concrete at 28day, B2(28.74MPa) and B1(21.33MPa) were higher in strength than C1(20.40MPa), which is in accordance with ASTM C1314 standard. The density of B2(2587kg/m3) and B1(2193kg/m3) were observed to be denser than C1(2153kg/m3) which is in accordance with ASTM C642 (2006) standard. The study concludes that Bacillus cereus-induced self-healing concrete presents a sustainable solution to the challenges of concrete cracking, offering potential benefits such as extended service life, reduced maintainability, and improved structural performance. This research contributes to the advancement of sustainable construction practices and supports the integration of biotechnology in modern building technology.