THE UNSTABLE EXTENSION OF INCLINED CRACKS UNDER UNIAXIAL TENSION AND COMPRESSION

Abstract

The path of unstable extension of the inclined cracks subjected to uniaxial tension and compression is determined theoretically using the criteria of maximum tangential stress (MTS), maximum tangential principal stress (MTPS), maximum tangential strain (MTSN), and strain energy density (SED) from the stress distribution existing prior to the onset of extension. Related experimental results (some of which are new) are presented to assess the accuracy. Out of the four criteria the MTPS criterion provides the best prediction of the experimental observations and the SED criterion is the least satisfactory.