Erodibility of Microbial Induced Carbonate Precipitation-Stabilized Sand under Submerged Impinging Jet

Abstract

Scour adjacent to foundation systems is a contributing factor to significant structural damage. Microbial induced carbonate precipitation (MICP) is investigated as an approach to improve the soil’s shear strength and stiffness and reduce the potential to scour. In this study, a submerged impinging jet system (mini JET apparatus) is used to assess the erodibility of MICP-treated sand with results presented in the context of data in literature. The results indicated that the critical shear stresses of the MICP-treated specimens increased one to three orders of magnitude, while the erodibility coefficients decreased by up to four orders of magnitude as the cementation level increases. The micro image analysis confirmed that cementation is achieved via precipitated calcium carbonate at the particle contacts. These results suggest that moderate to high levels of cementation using the MICP process is potentially an effective approach to reduce the sand’s erodibility.