This paper also provides numerical results based on the SED criterion,modified to deal with mode III fracture. Although the nonlinearities occurring during the tests and following the tracks by
Seweryn, a non-conventional application of the linear elastic SED as a fracture parameter has been proposed here. The approach has allowed to summarise all the data in a single scatterband,
regardless the notch shape and dimensions, showing the potentialities of the proposed criterion, which remains very simple to be applied and very useful as an engineering tool for preliminary fracture estimations. Good agreement between numerical predictions and experimental results has been found. Further investigations are surely necessary to be able to predict a priori the value of the critical radius also in those cases where linear elastic behaviour is not achieved during the tests. Another open point should be the application of the SED considering the real non-linear behaviour of the material but maintaining the simplicity and usefulness of this approach.