A DEM investigation on crushing of sand particles containing intrinsic flaws

Intrinsic flaws are an important factor affecting particle strength and breakage behavior and are closely related to the macroscopic behavior of granular soils, e.g., packing characteristics, strength, deformation, localization and failure behaviors, etc. In this paper, a novel DEM modeling approach for investigating the role of flaws on the particle crushing behavior is proposed. The idea is to use the realistic fracture surfaces obtained from the experiment as a basis for generating initial flaws in DEM in a statistical way. Firstly, nano-focus X-ray computed tomography technology was used to obtain the realistic particle information including particle morphology and a set of fracture surfaces. The particle information was then stored in several arrays and imported into the DEM to construct the particle model containing a reasonable set of initial flaws. Seven simulation cases were performed to study the role of initial flaws on the particle breakage behavior. Simulation results show that the proposed modeling approach is capable of reproducing the realistic particle breakage behaviors, including the small-strain stiffness, peak crushing load, fracture pattern and evolution of fragment shape parameters.