Effects of constitutive parameters on the accuracy of measured fracture energy using the DCB-specimen

Several methods exist to estimate the fracture energy for adhesive joints using the double cantilever beam specimen and linear elastic fracture mechanics. Since the mechanical properties of all adhesives are non-linear, errors are generated. By use of an exact solution experiments are simulated. These are evaluated with eight different methods. The influence of the constitutive parameters is systematically studied. This influence is small for most methods. The error due to the choice of evaluation method is considerably larger. One of the commonly used methods gives accurate results; the error is less than 3%. However, most methods yield substantial errors.