We measured experimentally the static friction force [Formula Presented] on the surface of a glass rod immersed in dry sand. We observed that [Formula Presented] is extremely sensitive to the closeness of packing of grains. A linear increase of the grain density yields to an exponentially increasing friction force. We also report on the periodicity of [Formula Presented] during gradual pulling out of the rod. Our observations demonstrate the central role of grain bridges and arches in the macroscopic properties of granular packings.
|Number of pages||5|
|Journal||Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics|
|Publication status||Published - Jan 1 1996|
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Statistics and Probability
- Condensed Matter Physics