Dresden 2003 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
DY: Dynamik und Statistische Physik
DY 46: Poster
DY 46.84: Poster
Thursday, March 27, 2003, 15:30–18:00, P1
Anisotropy in granular media: classical elasticity and directed force chain network — •Matthias Otto1, Jean-Philippe Bouchaud2, Philippe Claudin3, and Joshua E.S. Socolar4 — 1Institut für Theoretische Physik, Universität Göttingen,Bunsenstr. 9, D-37075 Göttingen, Germany — 2Service de Physique de l’Etat Condensé, CEA-Saclay, Orme des Merisiers, 91191 Gif-sur-Yvette Cedex, France — 3Laboratoire des Milieux Désordonnés et Hétérogènes (UMR 7603), 4 place Jussieu – case 86, 75252 Paris Cedex 05, France — 4Department of Physics and Center for Nonlinear and Complex Systems, Duke University, Durham, NC 27708, USA
A general approach is presented for understanding the stress response function in anisotropic granular layers in two dimensions. The formalism accommodates both classical anisotropic elasticity theory and linear theories of anisotropic directed force chain networks. Perhaps surprisingly, two-peak response functions can occur even for classical, anisotropic elastic materials, such as triangular networks of springs with different stiffnesses. In such cases, the peak widths grow linearly with the height of the layer, contrary to the diffusive spreading found in ‘stress-only’ hyperbolic models. In principle, directed force chain networks can exhibit the two-peak, diffusively spreading response function of hyperbolic models, but all models in a particular class studied here are found to be in the elliptic regime.