Stress Intensity Factors and Displacements for ARC Bend Samples Using Collocation

摘要

Stress intensity, crack mouth opening displacements, and load-line displacements were determined for the arc bend-chord support specimen using boundary collocation. Several inner radius (r1) to outer radius (r2) ratios were studied at each of two span (S) to width (W) ratios. The actual solution matrix is for S/W = 3, r1/r2 = 0.8, 0.6 0.4, and for S/W = 4, R1/R2 = 0.8, 0.7, 0.6. Also, the three-point bend single-edge specimen (SE(B) at both S/W = 3 and S/W = 4 was studied to examine the limiting behavior of the generated solutions. For all of the S/W = 3 cases, solutions were obtained for crack length to width ratios (a/W) from 0.2 to 0.6, and in the S/W = 4 cases, a/W was varied from 0.2 to 0.5. The solutions were obtained by the linear superposition of a pure bending stress, a pure shear stress, and a uniform normal stress on an annual segment. The magnitudes of the individual components depended upon the size of the annular segment and the S/W ratio. Wide range expressions were fit to the numerical solutions to make them applicable over a wider range of testing conditions and for inclusion in future revisions of E-399 on Plane-Strain Fracture Toughness Testing. (jhd)