Experimental Measures of Affine and Non-affine Deformation in Granular Shear
arXiv:cond-mat/0702334 · doi:10.1103/PhysRevLett.100.208302
Abstract
Through 2D granular Couette flow experiments, we probe failure and deformation of disordered solids under shear. Shear produces smooth affine deformations in such a solid and also irresversible so-called non-affine particle displacements. We examine both processes. We show that the non-affine part is associated with diffusion, and also can be used to define a granular temperature. Distributions for single particle non-affine displacements, $\dri$, satisfy $P_1(\dri) \propto \exp [-|\dri/Δr|^α]$ (). We suggest that the shear band forms due to a radially outward diffusive flux/non-affine motion which is balanced in the steady state by inward diffusion due to density gradients.
4 pages, 5 figures