Experimental study of the effect of bacillus megaterium bacteria on cement concrete

Abstract

Abstract The presence of voids in cement concrete may lead to a reduction in its performance when exposed to high shrinkage and settlement. This study focused on utilization of bacteria for improving the performance by reducing the voids in the concrete. Bacillus family bacteria were found to be the great healers for the concrete. Bacillus megaterium bacteria of bacillus family with a concentration of 108 CFU have been utilized in the current study. A total of 48 specimens were cast and tested for their mechanical strength and water absorption after 7 and 28 days of curing. The test results indicate that the compressive, split tensile and flexural strengths increased to 12.91%, 10.28% and 9.02% respectively after 28 days of curing as compared to standard M30 grade concrete mix. The water absorption value of bacterial concrete was also found to be less as compared to the standard concrete mix. This is because of the filling of the cracks in concrete due to calcite precipitation produced by the Bacillus megaterium bacteria. Therefore, the Bacillus megaterium bacteria of bacillus family can be effectively utilized to improve the mechanical strength by reducing the voids.