Length Scales From Elastic Buckling Of A Force Chain Under Confined Axial Compression

摘要

In a deforming densely packed granular material, the columnar force chains carry the majority of the load, while the surrounding weak network neighbours provide these chains lateral support. Despite this confinement, the discrete nature of the granular assembly renders these force chain columns particularly prone to failure by buckling. The focus of this paper is the elastic buckling of a single Ν+ 2 particle force chain under lateral support, using the techniques of Structural Mechanics. The minimum critical buckling load and its corresponding buckling mode are determined. We investigate the properties of this mode, specifically, the dependence of its wavelength and minimum critical load on material properties, boundary conditions and the number of particles in the chain. A possible link between these properties and the characteristic length scale of shear bands is explored.