We study the shearing of polydisperse and bidisperse media with a size ratio of 10. Simulations are performed with a the two dimensional shear cell using contact dynamics. With a truncated power law for the polydisperse media we find that they show a stronger dilatancy and greater resistance to shearing than bidisperse mixtures. Motivated by the practical problem of reducing the energy needed t...

We have considered the problem of elastic wave velocities in a matrix containing aligned ellipsoidal fluid-filled cracks. This problem is relevant o a variety of geophysical pplications, including crustal and mantle seismology and the behavior of stressed and dilatant rock. When the cracks are ellipsoids of revolution, the composite is transversely isotropic and is describable with five elastic...

We study the effect of the anisotropy induced by loading on the elastoplastic response of a two dimensional discrete element model granular material. The anisotropy of the contact network leads to a breakdown of the linear isotropic elasticity. We report on a linear dependence of the Young moduli and Poisson ratios on the fabric coefficients, measuring the anisotropy of the contact network. The...

Gassy clays containing large, discrete gas bubbles are widely spread in deposits shallow waters. The existence of may impair the original soil structure, resulting instability offshore foundations and occurrence submarine landslides. Although gassy clay was found to exhibit different undrained shear behaviors with variations initial pore water pressures volume fractions, more experimental studi...

This paper focuses on the presence of nodules insoluble materials within salt specimens, and their effect volumetric strain measurements dilatancy phenomenon. We analyzed experimental results over 120 conventional triaxial compression tests, found that in 20% cases, were atypical. also noted natural variability specimens can lead to a non-negligible data scattering when different are subjected ...