Issue 37

M. Mokhtarishirazbad et alii, Frattura ed Integrità Strutturale, 37 (2016) 114-123; DOI: 10.3221/IGF-ESIS37.16

C ONCLUSIONS

I

n this paper, the effect of applying a 40% overload on the behaviour of a crack under cyclic biaxial loading is studied with DIC technique. COD examinations showed the classical sequences of overload including retardation and recovery. A method including fitting the experimental displacement data to analytical solutions based on Williams' series development was also used for studying the biaxial fatigued cracks. This allowed the mixed-mode SIF (K I and K II ) and the T-stress to be estimated on two different samples, one subjected to an overload event and one without an overload. Results showed that applying 40% overload led to a 27% decrease in ∆K I after the crack propagated 0.388 mm. ∆K II for the sample which did not experienced overload cycle increased by 73% for a crack growth of 0.371 mm. It was also shown that DIC can effectively be used for studding the structures under biaxial loading.

A CKNOWLEDGEMENTS

F

inancial support of Junta de Andalucía through Proyectos de Excelencia grant reference TEP-3244; and University of Malaga through Campus de Excelencia Internacional del Mar (CEIMAR) through Líneas Emergentes program and for providing PhD exchange scholarship is greatly acknowledged.

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