A new fixture for fracture tests under mixed mode I/III loading

In this paper, a new loading fixture is suggested for exploring mixed mode I/III fracture experimentally. Then, the advantages of the fracture test configuration in comparison with the previously presented ones are introduced. Using finite element analysis, the crack parameters of the associated test specimen are obtained for various mixed mode loading conditions. The numerical results show that the designed loading apparatus can create various mode mixities from pure mode I to pure mode III. Subsequently, a series of fracture tests are conducted on PMMA using the proposed test configuration. It is shown that the results of fracture toughness and fracture angles obtained from the experiments are in relatively good consistency with those predicted from the well-known maximum tangential stress criterion.