• Corpus ID: 119362771

A Model for Athermal Strain Localization in Dry Sheared Fault Gouge

@article{Ma2017AMF,
  title={A Model for Athermal Strain Localization in Dry Sheared Fault Gouge},
  author={Xiao Ma and Ahmed E Elbanna},
  journal={arXiv: Geophysics},
  year={2017}
}
Shear banding is widely observed in natural fault zones as well as in gouge layers in laboratory experiments. Understanding the dynamics of strain localization under different loading conditions is essential for quantifying strength evolution of fault gouge, energy partitioning during earthquakes and characterizing rheological transitions and fault zone structure changes. To that end, we develop a physics-based continuum model for strain localization in sheared granular materials. The grain… 

A new hybrid numerical scheme for modelling elastodynamics in unbounded media with near-source heterogeneities

The Finite Difference (FD) and the Spectral Boundary Integral (SBI) methods have been used extensively to model spontaneously propagating shear cracks in a variety of engineering and geophysical

A hybrid finite element‐spectral boundary integral approach: Applications to dynamic rupture modeling in unbounded domains

The finite element method (FEM) and the spectral boundary integral method (SBI) have both been widely used in the study of dynamic rupture simulations along a weak interface. In this paper, we

References

SHOWING 1-10 OF 81 REFERENCES

A two‐scale model for sheared fault gouge: Competition between macroscopic disorder and local viscoplasticity

We develop a model for sheared gouge layers that accounts for the local increase in temperature at the grain contacts during sliding. We use the shear transformation zone theory, a statistical

Stability and localization of rapid shear in fluid‐saturated fault gouge: 1. Linearized stability analysis

Field observations of major earthquake fault zones show that shear deformation is often confined to principal slipping zones that may be of order 1–100 μm wide, located within a broader gouge layer

Stability and localization of rapid shear in fluid‐saturated fault gouge: 2. Localized zone width and strength evolution

Field and laboratory observations indicate that at seismic slip rates most shearing is confined to a very narrow zone, just a few tens to hundreds of microns wide, and sometimes as small as a few

Strain localization in a shear transformation zone model for amorphous solids.

A criterion is derived that determines which materials exhibit shear bands based on the initial conditions alone, and it is shown that the shear band width is not set by an inherent diffusion length scale but instead by a dynamical scale that depends on the imposed strain rate.

Frictional behavior and constitutive modeling of simulated fault gouge

This paper presents an investigation of the factional properties and stability of frictional sliding for simulated fault gouge. In these experiments we sheared gouge layers (quartz sand) under

Rate-dependent shear bands in a shear-transformation-zone model of amorphous solids.

The shear transformation zone (STZ) model, which resolves dynamics within a sheared material interface, predicts that the stress weakens with strain much more rapidly than a similar model which uses a single state variable to specify internal dynamics on the interface.

Grain fragmentation in sheared granular flow: weakening effects, energy dissipation, and strain localization.

It is shown that grain breakage is a weakening mechanism, significantly lowering the flow stress at large strain rates, if the material is rate strengthening in character, and that if the granular material is sufficiently aged, spatial inhomogeneity in configurational disorder results in strain localization.

Dynamic friction in sheared fault gouge: Implications of acoustic vibration on triggering and slow slip

Friction and deformation in granular fault gouge are among various dynamic interactions associated with seismic phenomena that have important implications for slip mechanisms on earthquake faults. To
...