Abstract:Enzyme-induced calcium carbonate precipitation (EICP) is a soil solidification and improvement technology with broad prospects. In order to study the mechanical fracture mechanism and meso-properties of EICP stabilized sand . In this paper, based on PFC 2D, the failure evolution laws of cemented sand specimens with different levels of cementation and different distributions of calcium carbonate in uniaxial compression tests were investigated. The results indicate that discrete element simulation considering the content, distribution, and particle contact model of calcium carbonate can better reflect the mechanical and deformation characteristics of the cemented sand specimens compared to indoor tests. Specimens with a low level of cementation undergo local shear failure, and the failure surface emerges in areas with lower calcium carbonate content in the middle. With an increase in cementation level, average particle displacement in sandy soil becomes smaller, and the direction of particle displacement is closer to the axial compression direction of the specimen leading to splitting failure with better overall stability. The higher the level of cementation is, the more uniform distribution of particle contacts in specimens is observed; resulting in slower extension rates for both crack growth and zones experiencing cementation failure.