Title: Shear-history memory in compressed granular packs

Author (Snapshot): Don Candela, UMass Amherst

Abstract:

Using simulations it is shown that a random pack of soft, frictional grains can remember the waveform of small shear strains applied while the pack is slowly compressed. When the grain pack is decompressed at a later time, the shear waveform is recalled (imperfectly) in time reversed order as shear stresses measurable on the system boundaries. This memory of bulk shear stresses is apparently due to transverse (frictional) stresses stored in contacts between grains that are formed as the pack is compressed.