Compact tension fracture specimen: Experimental and computational implementations on stress intensity factor

Abstract

This work concentrates on the characterization of the stress intensity factor range for a compact tension specimen tested under a uniaxial tensile fatigue loading condition. The experimental solution is obtained using a three-dimensional full-field optical technique, digital image correlation. The deformation field is measured and documented for distinct crack lengths. As a relevant fracture parameter, stress intensity factor is thus experimentally measured combined with a computational overdeterministic algorithm for different crack lengths. Moreover, to verify the performance of the proposed fracture model, the cracked compact tension specimen is elasto-statically resolved using advanced discretization techniques, such as the finite element method, the meshless radial point interpolation method and the meshless natural neighbour radial point interpolation method. The finite element method model is thereby analysed with ABAQUS© to enable computation of mode I stress intensity factor results based on strain energy release rate criterion for different crack measurements in addition to strain contours. Likewise, the resolution pattern is repeated for meshless methods, and analogous numerical solutions are thus obtained. Overall, the experimental and numerical stress intensity factor results are compared with an available solution (ASTM E647) exhibiting a reasonable agreement. The novelty of this investigation is the amalgamation of an experimental digital image correlation procedure with a computational overdeterministic algorithm and, most importantly, the meshless formulation performance in the linear elastic fracture mechanics.