Implementación de una estación didáctica para la predicción de los factores de concentración de esfuerzos usando correlación de imágenes digitales (DIC).

Abstract

This study focuses on the introduction of the theoretical and practical foundations of the Digital Image Correlation (DIC) technique for the calculation of stress concentrators to university students at EPN through the application of a laboratory DIC workshop. In the practice, an elastomer containing different shapes of notches is used as a test specimen, in which a pattern of random spots/dots is impregnated on its surface. The specimen is subjected to a tensile force in a universal traction testing machine, where the applied load is sequential or staggered to obtain images. The project evaluates three specialized image correlation packages: Digital Image Correlation Engine (DICe), Matlab's open source 2D Digital Image Correlation software Ncorr, and finally the GOM software. The obtained results are compared with the analytical solutions of the theory of elasticity and other formulas found in the literature with the values obtained from the stress concentrator around the different hole shapes. Finally, a numerical simulation is performed on a commercial FEA software to further compare the experimental file. The data suggest a good agreement between the analysis procedures that allow the correct introduction of the theoretical and experimental foundations of the Digital Image Correlation DIC among the EPN community.