Estimation on ureolysis-based microbially induced calcium carbonate precipitation progress for geotechnical applications

ABSTRACT

There are some key challenges in the geotechnical applications of microbially induced CaCO₃ precipitation technique. These challenges mainly arise from lack of enough control on precipitation patterns within the soil. Monitoring precipitation progress in treatment solution (biogrout) before injection provides useful information on controlling the precipitation pattern. In this study, a hybrid of electrical conductivity change measurements and precipitation mass measurements was proposed for the monitoring. The results were described as characteristic curves which would provide useful information on interpreting, estimating, and steering the precipitation pattern within the soil. The effects of some influencing factors on the precipitation patterns were also statistically investigated. XRD, FTIR, and SEM were used for the microscale identification analysis of the precipitated solids.

KEYWORDS:

• Biocementation
• biogeotechnical engineering
• biogeotechnology
• biogrout
• microbial geotechnics
• soil improvement

Acknowledgements

The authors would like to thank Assoc. Prof. Bahar Taneri and Assoc. Prof. Şükrü Tüzmen from the Department of Biological Sciences and Dr. Zülal Yalınca from the Department of Chemistry of the Eastern Mediterranean University, who have provided technical help and access to the Molecular Biology Laboratory for conducting the experimental study of this article.