Stress Intensity Factor

Abstract

Crackline-loaded edge- crack specimens are flat plate specimens which have a single crack notch extending normally from one edge and which are loaded in tension at posi? tions close to the intersection of the crack with that edge. These specimens are of inter? est in fracture-mechanics testing because they require comparatively little material and because there are some varieties for which the stress intensity factor K is almost inde? pendent of crack length over a considerable range. Stress intensity factors were determined for a variety of these specimens, all with straight boundaries, by boundary collocation of the Williams form of stress function. The boundary conditions were determined with the aid of another stress function due to Filon. The results presented are considered to be comprehensive enough for a wide vari? ety of applications of these specimens. Two complementary types of semifinite crackline-loaded specimen are treated in de? tail. The results for these specimens can be used graphically to obtain a useful prelim? inary estimate of the results for any finite specimen with straight boundaries. Boundary collocation analysis need then be conducted only on those cases which appear to be of most practical interest. The boundary collocation results were used to calculate values of the stress inten? sity coefficient KsW1/2/P for a crackline-loaded specimen of nonlinear contour. These values are in excellent agreement with the published experimental compliance data for this specimen configuration.