A finite element calculation of stress intensity factors by a modified crack closure integral

Applied Solid Mechanics Section, Battelle's Columbus Laboratories, Columbus, OH 43201, U.S.A.
Engineering Fracture Mechanics 01/1977; DOI: 10.1016/0013-7944(77)90013-3

ABSTRACT An efficient technique for evaluating stress intensity factors is presented. The method, based on the crack closure integral, can be used with a constant strain finite element stress analysis and a coarse grid. The technique also permits evaluation of both Mode I and Mode II stress intensity factors from the results of a single analysis. Example computations are performed for a double cantilever beam test specimen, a finite width strip with a central crack, and a pin loaded circular hole with radial cracks. Close agreement between numerical results given by this approach and reference solutions were found in all cases.

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