EXPERIMENTAL STUDY ON INTERNAL EROSION RESISTANCE OF MICROBIAL INDUCED CALCIUM CARBONATE DEPOSITION-CONSOLIDATED SILTY-SAND MIXTURES

Silty-sand mixtures, characterized by a blend of medium-coarse sand and fine particles (silt), are prevalent in various stratigraphic regions across the country. However, their poor stability and susceptibility to internal erosion pose significant challenges in engineering applications. Microbial Induced Calcium Carbonate Precipitation (MICP) is an innovative soil reinforcement technique that improves soil strength and reduces permeability by depositing calcium carbonate on sand particles and within pore spaces. This study investigated the anti-erosion performance of MICP-treated silty-sand mixtures through erosion tests. Key parameters, including erosion velocity and fine particle loss, were analyzed to validate the effectiveness of MICP in enhancing erosion resistance. The energy dissipation method, based on fine particle loss, was used for erosion sensitivity zoning and performance evaluation. The results indicated that the number of treatment cycles significantly influenced the erosion resistance index, followed by the cementation solution concentration, while fine particle content had a relatively minor impact. These findings provide valuable insights for mitigating natural hazards such as internal erosion in silty-sand mixtures.