The determination of strain fields based on displacements obtained via digital imagecorrelation (DIC) at the micro-strain level ( ≤ 1000 μm/m ) is still a cumbersometask. In particular when high-strain gradients are involved, e.g. in composite materi-als with multidirectional fibre reinforcement, uncertainties in the experimental setupand errors in the derivation of the displacement fields can substantially hamper thestrain identification process. In this contribution, the aim is to investigate the im-pact of lens distortions on strain measurements. To this purpose, we first performpure rigid body motion experiments, revealing the importance of precise correctionof lens distortions. Next, a uni-axial tensile test on a textile composite with spatiallyvarying high strain gradients is performed, resulting in very accurately determinedstrains along the fibers of the material.
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