Recently, a new nonlocal granular rheology was successfully used to predictsteady granular flows, including grain-size-dependent shear features, in a widevariety of flow configurations, including all variations of the split-bottomcell. A related problem in granular flow is that of mechanically-induced creep,in which shear deformation in one region of a granular medium fluidizes itsentirety, including regions far from the sheared zone, effectively erasing theyield condition everywhere. This enables creep deformation when a force isapplied in the nominally quiescent region through an intruder such as acylindrical or spherical probe. We show that the nonlocal fluidity model iscapable of capturing this phenomenology. Specifically, we explore creep of acircular intruder in a two-dimensional annular Couette cell and show that themodel captures all salient features observed in experiments, including both therate-independent nature of creep for sufficiently slow driving rates and thefaster-than-linear increase in the creep speed with the force applied to theintruder.
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