Experimental study of the geometrical effects in the localization of deformation

Abstract

We have studied the localization of deformation in a 2D packing model. The samples consist of regular packings of equal parallel cylinders (drinking straws). The local stress-strain characteristics, at the contact between two straws, shows a softening part, responsible for the localization of the deformation. We have analyzed the roughness of localization band, i.e., the width W of the localized zone versus its length L. Our results demonstrate the self-affine character of the localized zone: We find a power law, W\ensuremath{\sim}${\mathit{L}}^{\mathrm{\ensuremath{\zeta}}}$ with \ensuremath{\zeta}=0.73\ifmmode\pm\else\textpm\fi{}0.07, which is consistent with recent work on the ``weak'' disorder model.