Civil Engineering and Architecture Vol. 11(6), pp. 3754 - 3762
DOI: 10.13189/cea.2023.110637
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Performance of Bacillus Subtilis Based Microbial Concrete in Acidic Environment


Kunwar Dipendraditya *, B.K Singh
Department of Civil Engineering, School of Engineering and Technology, DIT University Dehradun, India

ABSTRACT

In practice, concrete as a part of the structure is exposed to various adverse atmospheric conditions, including temperature variation, acid and alkaline environments, varied humidity etc. Hence, its versatility in performance needs to be studied for all such conditions. Conventional materials form bacterial concrete with microbes, which lead to additional cementation by producing insoluble organic and inorganic compounds. This process of Microbe Induced Calcite Precipitation (MICP) leads to the formation of dense microstructure of concrete, forming a resultant concrete with higher compressive strength and lower permeability. However, the performance of microbial concrete under an aggressive environment needs to be studied as the bacterial population is significantly affected by it. In this study, the compressive strength of hardened concrete added with Bacillus Subtilis has been taken under consideration. The concrete specimens were prepared by adding Bacillus Subtilis microbes during the casting phase. All specimens were cured for 28 days under normal curing condition. Afterwards, these samples were kept inside the acidic solution of H2SO4 and HNO3 in a molar ratio of 2:1, having pH value of 3. The solution was prepared to keep simulation in view with the usual acidic environment around the concerned industries. Six cubes for each sample (with and without bacteria) were prepared and tested for compressive strength and water absorption after 28 days normal curing. Further, these specimens were cured by said acid solution for 45, 90 and 135 days and their compressive strength and mass loss tests were conducted. Results reveal that the compressive strength of bacteria treated concrete is better than that of corresponding control concrete. Also, it was observed that the specimens contain highest bacteria cell concentration when exposed to acid environment undergo minimum loss in compressive strength but the rate of loss increases with increasing exposure days. In addition, the mass loss study indicates higher resistance of microbial concrete against the acid environment.

KEYWORDS
Microbial Concrete, Bacillus Subtilis, Compression Strength, Water Absorption

Cite This Paper in IEEE or APA Citation Styles
(a). IEEE Format:
[1] Kunwar Dipendraditya , B.K Singh , "Performance of Bacillus Subtilis Based Microbial Concrete in Acidic Environment," Civil Engineering and Architecture, Vol. 11, No. 6, pp. 3754 - 3762, 2023. DOI: 10.13189/cea.2023.110637.

(b). APA Format:
Kunwar Dipendraditya , B.K Singh (2023). Performance of Bacillus Subtilis Based Microbial Concrete in Acidic Environment. Civil Engineering and Architecture, 11(6), 3754 - 3762. DOI: 10.13189/cea.2023.110637.