Orientation of shear bands for a rigid plastic frictional material in simple shear

Dynamics of shear bands in a dense granular material forced by a slowly moving rigid body.

We experimentally investigate the flow field in plane geometry around a slowly moving rigid finger in a dry, randomly packed granular medium. The finger enters the medium vertically from its free surface, in analogy with indentation tests on ductile materials. By developing a particle imaging velocimetry technique, we identify a localized flow around the finger, limited by two nearly symmetric ...

Shear-induced orientation of a rigid surfactant mesophase.

An optically clear, crystalline, gel-like mesophase is formed by the addition of water to a micellar solution consisting of a mixture of 0.85 M anionic surfactant sodium bis(2-ethylhexyl) sulfosuccinate (AOT) and a 0.42 M zwitterionic surfactant phosphatidylcholine (lecithin) in isooctane. At 25 degrees C and water to AOT molar ratio of 70, the system has a columnar hexagonal microstructure wit...

Numerical Computations For Shear Bands in an Antiplane Shear Model

We study numerically a model for shear bands that is loosely based on anti-plane shearing of granular material. In the model, a shear band is idealized to a jump discontinuity in the solution to the dynamic PDE. We do not explicitly incorporate small scale eeects within the shear band into the model{rather at the shear band we impose a jump condition which includes a length parameter modeling t...

Fluid depletion in shear bands.

How does pore liquid reconfigure within shear bands in wet granular media? Conventional wisdom predicts that liquid is drawn into dilating granular media. We, however, find a depletion of liquid in shear bands despite increased porosity due to dilatancy. This apparent paradox is resolved by a microscale model for liquid transport at low liquid contents induced by rupture and reconfiguration of ...

Propagation of Adiabatic Shear Bands