Features of static pressure in dense granular media

It is shown that the partial pressure, i.e. the contribution of contacts with a given force to the total average pressure, in a granular packing in quasistatic flow increases linearly from zero with the force level both in two and three dimensions. It reaches its maximum for the average force and decays for larger forces. We found that a well-defined sub-texture, composed of the contacts carrying a force below the average force, does not contribute to the shear stress, so that its contribution to the average pressure is mechanically similar to a hydrostatic pressure.