Investigation of Active Deformation Mechanisms in Natural Salt Rock Using Digital Image Correlation

Abstract The deformation behavior of natural, coarse-grained, salt rock is studied through optical observation during uniaxial compression tests on large representative cylindrical samples. High-definition images are continuously recorded throughout the loading and analyzed using digital image correlation techniques, allowing for the extraction of surface displacement and strain fields. Examination of the local strain maps and the corresponding microstructure previously characterized by Electron Backscatter Diffraction unveils the combined contribution of two distinct deformation mechanisms: crystal slip plasticity and grain boundary sliding, along with intra-crystalline damage.