Restraint of Particle Breakage by Biotreatment Method

The particle breakage and compressibility behavior of sands treated with microbially induced carbonate precipitation (MICP) has been investigated using oedometric compression tests. The acid washing technique was used to obtain the calcium carbonate (CaCO3) content and facilitate quantification of particle breakage by measurement of the particle size distribution (PSD). It was found that the compressibility was lower for specimens with a large CaCO3 content. Particle breakage increased with an increase in the stress or input work for specimens with approximately the same CaCO3 content. In addition, for a given applied stress or input work, MICP-treated specimens exhibited smaller particle breakage than untreated specimens, which shows that the MICP treatment can effectively restrain particle breakage.