Strength Improvement Studies Using New Type Wild Strain Bacillus cereus on Cement Mortar

This article presents details of the experimental studies carried out on cement mortar using Bacillus cereus and Bacillus pasteurii in different cell concentrations. Test results showed that the addition of bacterial cultures of both species, enhanced the compressive strength of cement mortar due to the bio-mineralization of calcium carbonate in the cement mortar matrix. The test results revealed 38% increase in compressive strength using B. cereus and 29% increase in the case of B. pasteurii over the control cement mortar. The chloride ingress capacity of B. cereus incorporated concrete found through rapid chloride permeability test confirms the reduction of chloride penetration compared to control sample. Characterization studies have been performed to confirm the calcite precipitation through different experimental techniques, viz. X-ray diffraction, scanning electron microscope, thermogravimetric analysis and Fourier transform-infrared spectroscopy.