On the extraction of notch stress intensity factors by the post-processingof stress data on the free edges of the notch

Following on the lines of a previous paper dedicated to cracked components by Ciavarella et al., here the case of a notch of semi-angle alpha is consi dered. Contrary to the crack case (alpha = 180 degrees), the free edges of the notch are easily accessible to experimental analysis; moreover they pro vide information about all the terms of the Williams series expansion of th e stress field about the notch apex, including the most important, i.e. the symmetric and antisymmetric singular term notch stress intensity factors ( N-SIFs), whereas for the crack case the mode I N-SIFs cannot be extracted f rom those stresses. Another important different feature is that symmetric a nd antisymmetric N-SIFs have different singularities, and in several cases they are so close that their contributions tend to overlap. Therefore, a si mple procedure is here proposed to use radial stresses, to separate their s ymmetric and antisymmetric contributions alpha priori by computing the sum and difference of the stresses on the two edges, to post-process these quan tities in the 'asymptotic region' with standard least-squares techniques an d to extract the N-SIFs. The method is applied to a simple case known in th e literature and solved by means of a boundary element code, and the result s are almost coincident with previous results, even with quite coarse mesh discretizations.