Hybrid moiré-numerical stress analysis around cutouts in loaded composites

A hybrid experimental-numerical method is presented for evaluating the stresses around holes or notches in orthotropic composites. Moiré-measured displacements and hybrid finite elements are employed. The geometric discontinuity of interest is surrounded by a hybrid element, which is a subregion within the physical structure. Measured displacements provide input information at nodal locations on the external boundary of the hybrid element. Little experimental data are needed, and the approach is accurate and effective. The method is demonstrated for a uniaxially loaded orthotropic laminate containing a central circular hole.

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