Analysis of transition from diffuse to localized failure in sandstone and concrete using Digital Image correlation

Abstract

The focus of this paper is the transition from diffuse to localized failure of sandstone and concrete specimens under uniaxial compression and correlation between macro responses and localized deformations at different stages of deformation. Digital Image Correlation (DIC) technique is applied to obtain full-field strain evolution that allows the identification of bifurcation from homogeneous to localized deformation. The obtained results show different bifurcation characteristics of sandstone, normal strength concrete and high strength concrete under uniaxial compression. The transition from diffuse to localized failure is observed to be gradual even for very brittle behavior with snap-back. Statistical distribution of strain and its evolution during the transition from diffuse to localized failure are investigated to provide the form of strain distribution and evolution at a scale lower than the macro scale.