Abstract
The objective of this paper is to develop the load separation method for evaluating the ηpl and ηpl CMOD plastic factors used in the J estimation approach based on load versus displacement records. Appropriate forms for the geometry and deformation functions have been suggested from the EPRI Handbook solutions to produce the separable form for the load. The obtained functions are applied to evaluate the ηpl and ηpl CMOD plastic factors for center cracked tension specimen. The present load separation method gave results which are somewhat different from the estimated values of ηpl given in the literature. For shallow cracks, the ηpl and ηCMOD pl plastic factors show considerable variation with crack size and the strain hardening exponent. For a deeply cracked CCT specimen, the ηCMOD pl factor tends to the ηpl factor and equals approximately unity.
Abbreviations: CCT – center cracked specimen; CMOD – Crack Mouth Opening Displacement; EPRI – Electric Power Research Institute; FEM – Finite Element Method; LLD – Load Line Displacement.
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Matvienko, Y. Separable functions in load separation for the ηpl and ηpl CMOD plastic factors estimation. International Journal of Fracture 129, 265–278 (2004). https://doi.org/10.1023/B:FRAC.0000047785.02563.c3
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DOI: https://doi.org/10.1023/B:FRAC.0000047785.02563.c3