The present experimental investigations are taken up to study the strength characteristics in ordinary grade concrete and standard grade of concrete with and without the addition of Bacteria Bacillus Subtilis. Based on earlier research works, 105 cells/ml concentration bacteria is selected. A technique is adopted in the formation of concrete by utilizing microbiologically induced calcite CaCO3 precipitation. Microbiologically Induced Calcite Precipitation (MICP) of Bacillus Subtilis is a common soil bacterium that can induce the precipitation of calcite. The present works deal with the bacterial concrete. M20 and M30 grades are chosen in this work, where the mix design is prepared by IS: 10262-2009. In this present research, 36 number of cubes, cylinders, and prisms are casted to get the performance of the bacterial concrete which is tested for compressive strength, split tensile strength, and flexural strength. Addition of bacteria shows increase in compressive strength, split tensile strength, and flexural strength. Experimental results on bacterial concrete show maximum increase in the mechanical properties, i.e. compressive strength, split tensile strength, and flexural strength for both M20 Grade & M30 Grade when 30% cement is partially replaced with fly ash and 30% fine aggregate is partially replaced with foundry sand. Bacteria concrete shows 36.5%, (ie) 29.79% increase in 28 days compressive strength when compared with normal concrete for M20 and M30 grades, respectively.
