The Role of Friction in Granular Media

Abstract

It is widely assumed that both interlocking and frictional resistance contribute to the strength of aggregates of loose particles, but there have been few systematic studies. Most that there are have started with the assumption, manifestly untrue, that principal directions of stress and strain necessarily coincide. In this paper, certain regular two-dimensional packings are examined on the basis of a more general theory that discards this assumption, and the results are used to draw tentative conclusions concerning the behavior under plane strain conditions of random aggregates of particles which are macroscopically isotropic.