English

Continuum modeling of mechanically-induced creep in dense granular materials

Soft Condensed Matter 2015-06-22 v1

Abstract

Recently, a new nonlocal granular rheology was successfully used to predict steady granular flows, including grain-size-dependent shear features, in a wide variety of flow configurations, including all variations of the split-bottom cell. A related problem in granular flow is that of mechanically-induced creep, in which shear deformation in one region of a granular medium fluidizes its entirety, including regions far from the sheared zone, effectively erasing the yield condition everywhere. This enables creep deformation when a force is applied in the nominally quiescent region through an intruder such as a cylindrical or spherical probe. We show that the nonlocal fluidity model is capable of capturing this phenomenology. Specifically, we explore creep of a circular intruder in a two-dimensional annular Couette cell and show that the model captures all salient features observed in experiments, including both the rate-independent nature of creep for sufficiently slow driving rates and the faster-than-linear increase in the creep speed with the force applied to the intruder.

Keywords

Cite

@article{arxiv.1408.3884,
  title  = {Continuum modeling of mechanically-induced creep in dense granular materials},
  author = {David Henann and Ken Kamrin},
  journal= {arXiv preprint arXiv:1408.3884},
  year   = {2015}
}