On the observation with polarised light of a granular medium under stress
Paper in proceedings, 2013

Whereas a two dimensional assembly of photoelastic discs shows clear coloured fringes when viewed with polarised light, a three dimensional granular medium composed of glass beads or grains shows structured patterns in the form of stripes of light of varying intensity which appear to have orientation related to the overall direction of major principal stress. Any light ray passes through many individual grains, each of which contributes to the retardation of the polarised light which emerges from the sample. The retardation within a grain is the result of nonuniform stress states within that grain which themselves result from the distribution of the contact forces between neighbouring grains in the assembly. In this paper we combine the framework of Jones calculus and the stress optic law in order to calculate and predict the effect that the randomly distributed contact forces on randomly distributed grains should have on the intensity of the light emerging from such a complex three dimensional assembly.

Author

Jelke Dijkstra

Chalmers, Civil and Environmental Engineering, GeoEngineering

Proceedings of Experimental Micromechanics for Geomaterials Joint workshop of the ISSMGE TC101-TC105

Areas of Advance

Building Futures (2010-2018)

Subject Categories

Geotechnical Engineering

More information

Created

10/7/2017