Micro-mechanical analysis of deformation characteristics of three-dimensional granular materials

摘要: The deformation characteristics of idealized granular materials have been studied from the micro-mechanical viewpoint, using Bagi’s three-dimensional formulation for strain tensor [Bagi, K., 1996. Mechanics Materials 22, 165–177]. This is based on Delaunay tessellation space into tetrahedra. set edges tetrahedra can be divided physical contacts and virtual between particles. expresses continuum, macro-scale as an average over all edges, their relative displacements (between two successive states) complementary-area vectors. latter vector a geometrical quantity determined i.e. structure particle packing. Results Discrete Element Method simulations isotropic triaxial loading polydisperse packing spheres used to investigate statistics branch vectors (subdivided contacts) edges. investigated are probability density functions averages groups with same orientation. It shown that these represented by second-order Fourier series in edge orientation. Edge orientations distributed isotropically, contrary contact orientations. lengths normal component isotropically (with respect orientation) values related each other volume fraction assembly. components zero average. The total assembly, given follows uniform-strain prediction. However, neither network nor has this property. displacement direction (determined vector) smaller than according assumption, while larger. caused high interparticle stiffness hinders compression. reverse observation holds tangential vector. contribution empty therefore very important understanding prediction materials.