Compact Shear Specimen for Mode Ⅱ Fracture Tests: Analysis and Fracture Interpretation

摘要

The work presents theoretical analysis and fracture interpretation of Compact Shear (CS) specimen for Mode Ⅱ fracture testing of materials. Two fracture criteria are used: the maximum circumferential stress criterion and the criterion of minimum strain energy density. The problem for two parallel crack s in an infinite body under shear loading as in the CS specimen is simplest model for this investigation. Previously obtained results for stress intensity factors (Petrova, Sadowski, 2012) are used in this investigation. The interaction of the cracks leads to mixed-mode loading conditions near the crack tips. The dominant stress intensity factor is Mode Ⅱ K_Ⅱ, but K_Ⅰ is also non-zero. Using the fracture criteria the direction of crack propagation as well as the critical condition under which the crack would initiate is calculated. The influence of the geometry of the problem, i.e. the crack inclination angle to the remote shear loading, distance between the cracks, on the main fracture characteristics is investigated.