Shearing motion of a fluid-saturated granular material

We discuss the application of a recently developed theory of multiphase mixtures to fluid-saturated granular materials. The theory includes the incompressibility of each phase, but unlike other theories of the type, does not require pressure equilibrium between the phases. We do a theoretical study of the motion of this material in a viscometric simple shearing apparatus. It is shown that simple shearing generally does not occur. Typically, in the vicinity of a boundary, if the solid volume fraction is low, a layer of high shear rate occurs, while if the solid volume fraction is high, a ''locking'' phenomenon occurs. Otherwise, there is a tendency for particles to accumulate in regions of low shear rate