Biocementation through Microbial Calcium Carbonate Precipitation

Abstract

Biocementation through microbial carbonate precipitation is a new branch of microbial geotechnology that deals with the applications of microbiological methods to produce cemented materials used in engineering. The primary consideration of these applications is to improve the geophysical properties of soil so that it will be suitable for construction and environmental purposes. The applications of biocementation would require an interdisciplinary research at the confluence of microbiology, ecology, geochemistry, civil and environmental engineering. This new field has the potential to meet society’s expanding needs for innovative treatment processes that improve soil engineering properties. This paper presents an overview of biocementation, particularly through microbial calcium carbonate (CaCO₃) precipitation, and non-destructive geophysical techniques for real-time monitoring of soil engineering properties. Focus is then narrowed to an example of laboratory-scale test of biocementation of sandy soil and measurement of strength development by shear wave velocity (V_s). Other analytical results included microscopic imaging by scanning electron microscope (SEM) and identification of CaCO₃ precipitation presented in biocemented sand by X-ray diffactometer (XRD) were discussed. Potential advantages and envisioned applications of biocemented soil improvement are identified.