Precursors to avalanches in a granular monolayer

Abstract

We investigate the stability of a granular monolayer composed of spherical grains on an inclined plate. When the tilt angle α increases, some reorganizations are observed throughout the pile. The packing fraction ρ of the packing evolves by successive jumps. Those discontinuous events precede the collapse of the pile at a critical angle αc. The occurrence of precursors before avalanches is modeled by stop-and-go motions of blocks due to the competition between sliding friction and the Janssen effect. © 2006 The American Physical Society.