On the use of digital image correlation method for determining the stress field at blunt V-notch neighborhood

This paper investigates the ability of digital image correlation method (DIC) in determining accurate stress field around blunt V-notches. The polymeric material of PMMA is selected as the testing material and the well-known specimen of single edge notch tension (SENT) as the testing specimen. The experimental method of DIC is used and pure mode I tests are conducted on blunt V-notched samples with five different notch opening angles and two various notch tip radii. The data points obtained from DIC are used to calculate the notch stress intensity factors (NSIFs). To do so, the experimental data points are fitted to the asymptotic analytical solution of blunt V-notches by using the least square approach. The NSIFs obtained from DIC tests are also compared with those calculated from the finite element (FE) analysis of the specimens and good accuracy of the procedure is proved. Finally, a discussion on the effects of different DIC parameters on the calculated results is presented.