Study the Effect of Bacillus Cereus on the Strength Characteristics of Rice Husk Ash Concrete
The effect of Bacillus cereus on the mechanical properties of the concrete formed with 20% replacement of Rice
Husk Ash to the weight cement is presented in the study. For the purpose of this study, a control mix was designed to have
28-day strength of 20 MPa in which cement was replaced with RHA by 20% of its weight. Then Bacillus cereus was
introduced in the mix in the concentration of 5%, 10%, and 15%. Tests were for performed for compression strength, water
absorption, and impact strength. Results showed that the introduction of the Bacillus cereus in the concrete improved its
compressive strength to 33% than that of the control mix for 15% concentration of Bacillus cereus at 28 days of curing.
Bacillus cereus of with the concrete reduced the water absorption from 2.4% to 1.7% at 15% concentration, confirming the
calcite precipitation. Scanning Electron Microscopy and X-Ray Diffraction spectroscopy on the control sample and the
sample with 15% Bacillus cereus broth at 28 days of curing exhibited the formation of additional CSH, calcite precipitation
in the micro-pores and improved the microstructure of the concrete at 15% Bacillus cereus broth and made concrete matrix
denser. All these findings indicated that the replacement of RHA with the introduction of Bacillus cereus improved the
mechanical properties of concrete.
Keywords - Bacillus cereus, Rice Husk Ash, Compression Strength, Scanning Electron Microscopy.