in this paper, a higher order continuum model is presented based on the cosserat continuum theory in 3d numerical simulation of shear band localization. as the classical continuum models suffer from the pathological mesh-dependence in strain softening models, the governing equations are regularized by adding the rotational degrees-of-freedom to conventional degrees-of-freedom. the fundamental r...

[1] Conditions for shear and compaction localization are examined for stress states on an elliptic yield cap in the space of Mises equivalent shear stress t and mean normal compressive stress s. Localization is predicted to occur when the slope of the hydrostatic stress versus inelastic volume strain curve falls to a critical value kcrit. When applied to the standard triaxial test, the analysis...

The effect of small-amplitude periodic shear on annealing a band in binary glasses is investigated using molecular dynamics simulations. first introduced stable via large-amplitude shear, and then amorphous samples are subjected to repeated loading during thousands cycles at strain amplitudes below the yield strain. It was found that with increasing amplitude, relocated deeper potential energy ...

This study aims to investigate the effects of geometric imperfections on buckling of thin cylindrical shells due to global shear. To this end, more than 320 finite element models of cylindrical shells with different diameter to thickness ratios were prepared. Random imperfections with different amplitudes were applied to numerical models. The results revealed that global buckling of cylindrical...

We study the transient drag force FD on a localized intruder in a granular medium composed of spherical glass particles. A flat plate is translated horizontally from rest through the granular medium to observe how FD varies as a function of the medium's initial volume fraction, ϕ. The force response of the granular material differs above and below the granular critical state, ϕc, the volume fra...

At room temperature, plastic flow of metallic glasses (MGs) is sharply localized in shear bands, which are a key feature of the plastic deformation in MGs. Despite their clear importance and decades of study, the conditions for formation of shear bands, their structural evolution and multiplication mechanism are still under debate. In this work, we investigate the local conditions at shear band...

A system of equations modeling antiplane shear in a granular material is considered. The model includes the possibility of localization of strain, and the subsequent development of shear bands. This behavior is captured in our analysis of the Riemann initial value problem, in which an initial discontinuity propagates as a combination of moving waves and a stationary shear band. The analysis is ...

Granular materials will segregate by particle size when subjected to shear, as occurs, for example, in avalanches. The evolution of a bidisperse mixture of particles can be modeled by a nonlinear first order partial differential equation, provided the shear (or velocity) is a known function of position. While avalanche-driven shear is approximately uniform in depth, boundary-driven shear typica...

Thermal runaway instability induced by material softening due to shear heating represents a potential mechanism for mechanical failure of viscoelastic solids. In this work we present a model based on a continuum formulation of a viscoelastic material with Arrhenius dependence of viscosity on temperature and investigate the behavior of the thermal runaway phenomenon by analytical and numerical m...