A discrete element method for interaction between flexible meshes and irregularly shaped granular materials

Abstract

The numerical simulation of interactions between flexible mesh structures and particles with irregular shapes presents significant challenges in the discrete element method (DEM). To address these problems, a DEM framework based on the Minkowski sum model is developed to effectively model such interactions. This framework accurately captures large deformation behaviors and complex mechanical responses through advanced Minkowski sum computation algorithms. Particles are represented as dilated polyhedral models, while flexible meshes are modeled using chain-linked cylindrical and spherical elements. This approach enables the simulation of both static and dynamic interactions across a wide range of geometric and mechanical conditions. To validate this model, a series of numerical examples were conducted, including the static deformation of flexible chains, particle impacts on flexible meshes, the influence of mesh geometry on rockfall protection, and the collapse of granular columns both with and without mesh constraints. The numerical results were compared to analytical results, confirming the accuracy of the model. Simulations indicated that triangular mesh geometries outperformed square and hexagonal meshes in reducing tensile force concentrations. Furthermore, the results demonstrated that flexible mesh structures effectively inhibited particle spreading during granular column collapse, thereby enhancing the overall integrity and stability of the system.