Re-evaluation of the strain concentration factor through elasto-plastic analyses
Keywords:digital image correlation, elasto-plastic strain variation, finite elements, effective strain concentration factor, V-notches
Digital image correlation and three-dimensional finite element investigations are done for analyzing strain concentration for a semicircular notch and two V-notches with different radii. Along the notch bisector normalized true opening strains are represented as a function of the normalized distance from the notch root. In the linear elastic domain a comparison to an analytical solution is also done. Strain variations in the elasto-plastic domain show that the experimental normalized strains are greater than the numerical ones, both close to the notch root and over the whole ligament. The calculation of an effective strain concentration factor for V-notches is done and its variation based on experimental results proves to be much closer to real phenomena of strain distribution in the elasto-plastic domain.
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