Determining the stress intensity factors KI, KII and the T-term via the conservation laws using the boundary element method

✍ Scribed by P.C. Olsen

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 874 KB
• Volume: 49
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(94)90110-4

✦ Synopsis

A new method for determining the stress intensity factors K, and K,, is presented. The method is based on the conservation laws, from which the property that the J,, J, and L integrals are zero for any closed path of integration is utilized. The integrals above are evaluated numerically for a circular path surrounding the crack tip and along the crack faces, ending, however, a distance A from the tip. At the distance A, all fields are replaced by the singular first-order expansion series, including the T-term for r~,, Based on the J,, J, and L integrals, numerically evaluated as described above, equations are derived, from which both the stress intensity factors K, and K,,, as well as the T-term are determined. Numerical tests based on the boundary element method are presented, in which the accuracy of the method is demonstrated.

The total energy release rate. represented by the J, integral, is typically determined with an accuracy of within l-2%. The distribution of the total energy release rate between mode I and mode II is, however, less accurately determined. The T-term is determined with a rather large uncertainty.