Investigating strength and deformation characteristics of microbially induced calcite precipitation treated loose sand

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2020-9
Duman, Emre
Microbially induced calcite precipitation (MICP) is a recently proposed novel environmentally friendly ground improvement method that is alternating to conventional ground improvement techniques. MICP has been under intense investigation by researchers from different civil engineering sub-disciplines to mitigate problems related to crack propagation of concrete, insufficient soil strength characteristics, soil erosion, asphalt cracks, etc. This study focuses on the effect of MICP treatment on the strength and volumetric behavior of loose sands by performing isotropically consolidated drained triaxial tests under 100, 200, and 400 kPa effective confining pressures. Various injection schemes (different numbers of cementation solution treatments and cementation solution concentration) were investigated within the concept of this study. MICP treated sands exhibit higher peak deviatoric stress, stiffness, and dilation. An increase in peak shear strength is hindered by the increase in confinement as the ratio of the peak deviatoric stress of treated and untreated sand is lower at higher confinement pressures. Lastly, an increase in treatment numbers and concentration enhanced the abovementioned properties

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Citation Formats
E. Duman, “Investigating strength and deformation characteristics of microbially induced calcite precipitation treated loose sand,” M.S. - Master of Science, Middle East Technical University, 2020.