A nonlinear theory of plasticity is proposed which facilitates the solution of a restricted class of plane strain problems. An anisotropic approximation to a real material is utilized with the characteristic directions chosen a priori. The formulation is in terms of displacements and sufficient displacement boundary conditions must be prescribed in order to solve the resulting classical wave eq...

Synchrotron x-ray imaging and stress measurements of diamond-anvil cell gaskets revealed large elastic strains at the diamond tip at a pressure of 300 gigapascals. The diamond, generally considered a rigid body, bent 16 degrees over a distance of 300 micrometers without failure. To complement these measurements, a technique was developed that permits x-ray diffraction to be measured through a b...

Earthquakes far from tectonic plate boundaries generally exploit ancient faults, but not all intraplate faults are equally active. The North American Great Plains exemplify such intraplate earthquake localization, with both natural and induced seismicity generally clustered in discrete zones. Here we use seismic velocity, gravity and topography to generate a 3D lithospheric density model of the...

Taiwan is a young orogenic belt with complex spatial distributions of deformation and earthquakes. We have constructed a three-dimensional finite element model to explore how the interplays between lithospheric structure and plate boundary processes control the distribution of stress and strain rates in the Taiwan region. The model assumes a liberalized power-law rheology and incorporates main ...

A macroscopic model describing elastic-plastic solids is derived in a special case of the internal specific energy taken in separable form: it is the sum of a hydrodynamic part depending only on the density and entropy, and a shear part depending on other invariants of the Finger tensor. In particular, the relaxation terms are constructed compatible with the von Mises yield criteria. In additio...

For two simple setups it is discussed, how dissipative grain-grain interactions give rise to unexpected properties on large scales. In the rst example, a spherical particle rolling along a rough surface experiences an eeective viscous friction on large time scales. It is due to temporal correlations among collisions with incomplete normal restitution. The second example is a sheared granular pa...