Biocementation as a Pro-Ecological Method of Stabilizing Construction Subsoil

Abstract

The principle of sustainable development imposes an obligation on societies to manage natural resources rationally and to care for the quality of the environment, by, among other things, reducing CO2 emissions. Alternative ways of stabilising building substrates by increasing their shear strength (cu) are increasingly being sought. This paper presents how microorganisms can influence cu and thus the load-bearing capacity of building substrates. Tests were performed in a triaxial compression apparatus in three variants. The first variant of testing was carried out on cemented soil samples, which were cemented in situ. The next two series of tests were performed on reconstructed samples, i.e., natural soil and soil inoculated with a solution of Sporosarcina pasteurii bacteria. The results obtained show that carbonate cementation increases the shear strength of the soil; in addition, this biomineralization-induced cementation gives higher cu results than natural carbonate cementation.

Keywords

• shear strength
• stabilization
• bio-cementation
• <i>Sporosarcina pasteurii</i>
• MICP (microbially induced calcite precipitation)