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Crack tip stress intensity factors calculated by dual finite element analysis

Published online by Cambridge University Press:  04 July 2016

D. J. Allman*
Affiliation:
Royal Aerospace Establishment, Farnborough

Extract

Stress intensity factors for centre and edge cracks in finite elastic sheets are calculated from potential energy and complementary energy release rates by dual analysis with simple compatible and equilibrium finite elements. Comparison with very accurate results of other authors who employ special singular functions to model a crack tip provides compelling numerical evidence that the calculated stress intensity factors behave respectively like lower and upper bounds to the exact values. The bound-like character of such results has been reported before in another context, though there are no known bounding principles which strictly apply to finite bodies.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1990 

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