An extended and integrated digital image correlation technique applied to the analysis of fractured samples
The equilibrium gap method as a mechanical filter
Keywords:
digital image correlation, equilibrium gap method, extended finite element methodAbstract
To reduce the measurement uncertainty, a measurement technique is proposed for estimating full displacement fields by complementing digital image correlation with an additional penalization on the distance between the estimated displacement field and its projection onto the space of elastic solutions. The extended finite element method is used for inserting discontinuities independently of the underlying mesh. An application to the brittle fracture of a silicon carbide specimen is used to illustrate the application. To complete the analysis, the crack tip location and the stress intensity factors are estimated. This allows for a characterization of the measurement and identification procedure in terms of uncertainty.
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