Effect of loadline shift on applied crack tip stress intensity in WOL specimens

✍ Scribed by N.S. Cheruvu; J. Anello; J.K. Donald; G.M. Connelly

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 933 KB
• Volume: 19
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(84)90149-8

✦ Synopsis

A change in applied stress intensity due to shifting of load line from the pin hole to a wedge located on the outside edge of the notch has been investigated by: (1) finite element analysis, (2) measurements of front face crack opening displacement and (3) strain relaxation near the crack tip.

Results show that this wedge loading procedure will result in a significant drop, up to a factor of two, in applied stress intensity. The drop in stress intensity is inversely related to the crack length (expressed by a/W). This drop in stress intensity is due to overall specimen distortion because of load line shift and local deformation of the wedge and notch surfaces. Implications of this drop on Stress Corrosion Cracking results are discussed. For reliable stress corrosion testing, modifications in specimen geometries and loading procedures are suggested.