Numerical modeling and analysis of suffusion patterns for granular soils

Migration of fine particles through constrictions between coarser fabrics by seepage force is the process termed suffusion. A coarser soil structure resulted from fines loss will lead to change in hydraulic and mechanical properties such as increased permeability, decreased strength and stability which can cause significant settlement or failure of the levees, embankments and dams. This paper presents a coupled Computational Fluid Dynamics and Discrete Element Method (CFD-DEM) approach to model the suffusion process. The concept of transition layer is defined and used to explain the suffusion process and patterns. The effects of particle size distribution, seepage velocity, fines content and initial void ratio on the transition layer in suffusion are investigated.