Analysis of localization in brittle materials through optical techniques

This paper is devoted to the experimental analysis of strain localization in rock like specimens subjected to uniaxial compression. Two different techniques are involved in this research: stereophotogrammetry and laser speckle photography. The strain fields obtained by these techniques exhibit a homogeneous response followed by a strain localization before the peak of the load verses displacement curve. These observations allow one to choose the appropriate mechanical constitutive equations to describe the behavior of such materials.