Variational Methods for Discrete Models of Granular Materials

Granular mechanics is defined as the mechanics of materials with granular texture in which the role of grain interactions is paramount. The description of the mechanical behavior of these material systems begins from the conception of grain interactions. From this point of departure, either discrete or continuum descriptions can be elaborated. Discrete models of granular materials aim to describe their behavior by tracking grain trajectories in simulated grain assemblies according to formulated equations of motions. The behavior at the scale of the grain assembly (the so-called “macroscopic” behavior) may then be deduced through certain averaging procedures. The formulations of grain-interaction models and the discrete and continuum descriptions of granular materials, based upon the variational methods, are described in the two companion chapters.