  We study by means of molecular dynamics simulations of periodic shear cells,
the influence of particle shape on the global mechanical behavior of dense
granular media. Results at macro-mechanical level show that for large shear
deformation samples with elongated particles, independent of their initial
orientation, reach the same stationary value for both shear force and void
ratio. At the micro-mechanical level the stress, the fabric and the inertia
tensors of the particles are used to study the evolution of the media. In the
case of isotropic particles the direction of the principal axis of the fabric
tensor is aligned with the one of the principal stress, while for elongated
particles the fabric orientation is strongly dependent on the orientation of
the particles. The shear band width is shown to depend on the particle shape
due to the tendency of elongated particles to preferential orientations and
less rotation.
