Investigation of Influencing Factors on the Engineering Properties of Microbially Induced Calcite Precipitation (MICP) Treated Soils

Microbially Induced Calcite Precipitation (MICP) is an emerging bio-geotechnical soil improvement technique to enhance the engineering performance of soil. Application of biotechnology has been suggested as an environmental-friendly alternative to conventional approaches. MICP involves using bacteria to hydrolyze urea into carbonate ions through bacterial metabolism. The carbonate ions combine with calcium ions to produce calcite crystal precipitates, which fill the soil pores and bind the soil grains together. In this project, the effects of several influencing factors on the engineering properties of the MICP treated silica sand are investigated. Permeability and unconfined compressive strength tests will be carried out to characterize the engineering properties of the treated sand. Precipitation patterns of calcite crystals within the sand after MICP treatment will be investigated using Scanning Electron Microscopy (SEM).