Synergistic Effects of CTP and Bacillus megaterium on Concrete Properties

Concrete deterioration is primarily caused by shrinkage, temperature changes, and reinforcement corrosion, which lead to crack formation. Continuous external loading can cause cracks to widen and form a network of cracks, enabling the infiltration of harmful gases, liquids and moisture, which weakens the strength and in turn the durability of concrete. Consequently, implementing measures to prevent degradation and to enhance the longevity by increasing durability of concrete is crucial. Continuous research efforts all around the globe have focused on enhancing concrete strength and durability using high-quality materials, additives including Supplementary Cementitious Materials (SCMs), and fibers. Ceramic Tiles Powder (CTP), fly ash, silica fume, and other materials have gained attention as SCMs, with CTP showing potential due to its high silicate and aluminum oxide content. The use of Bacillus megaterium in CTPembedded concrete has scarcely been studied, prompting this research to explore its feasibility. This present research work investigates the strength and durability of M30 grade concrete with use of Bacillus megaterium at a concentration of 10⁵ cells/ml and with varying cement replacement percentages (5%, 10%, 15%, and 20%) using CTP. The test results indicate about 25% improvement in compressive strength of concrete with 10% cement replacement using CTP and Bacillus megaterium of concentration 10⁵ cells/ml. Petrographic analysis showed better surface composition, while SEM (Scanning Electron Microscope) images revealed increased calcite precipitation and reduced voids.