A Critical Review of Engineering Properties of Soil Treated with Microbially Induced Calcium Carbonate Precipitation (MICP)
Abstract
Microbially induced calcium carbonate precipitation (MICP) is a process that leverages microbial metabolic activity to facilitate biochemical interactions with surrounding chemical compounds, resulting in the precipitation of calcium carbonate. This mineralization process enhances soil properties by filling pores, binding soil particles, and reducing permeability, resulting in a significant increase in soil strength and stability. MICP holds great potential for various geotechnical and environmental engineering applications, including mitigating soil liquefaction, stabilizing erosion-prone slopes, remediating contaminated soils, and controlling seepage in infrastructure such as dams and tunnels. This review paper provides a concise overview of the cementation mechanism involved in MICP and the urea hydrolysis process, based on recent research findings. Key factors in evaluating the engineering properties of MICP-treated soils include compressive strength, permeability, stiffness, durability, volumetric behavior, shear wave velocity, and microstructural characteristics. Future research directions are discussed to guide the further development of MICP technology, focusing on the cost-effective bacterial strains, improved treatment uniformity, and the durability of MICP-treated soils under combined erosion and leachate conditions.