Micro-mechanical analysis and modelling of granular materials loaded at constant volume

The present paper is devoted to the analysis and the modelling of the local phenomena, which are observed in a two-dimensional granular media loaded at constant volume. A micro-mechanical approach is followed here combined with a computer simulation method. Local phenomena observed during test are used to provide some necessary elements to build realistic models. The importance of the induced anisotropy during the test is especially shown, as well as its necessary link to the dilatancy. To illustrate the study a model based on a micro-mechanical approach is validated.