FORCE FLUCTUATIONS IN BEAD PACKS

Experimental observations and numerical simulations of the large force inhomogeneities present in stationary bead packs are presented. Force s much larger than the mean occurred but were exponentially rare. An e xactly soluble model reproduced many aspects of the experiments and si mulations. In this model, the fluctuations in the force distribution a rise because of variations in the contact angles and the constraints i mposed by the force balance on each bead in the pile.