Abstract
Closely spaced asymmetric cracks in a biaxial cruciform specimen interacting at different orientations is studied by digital photoelasticity. Isochromatic fringe patterns are captured under biaxial loading conditions with varying biaxial ratios from 0 to 1, zero indicating uniaxial loading and one indicating equi-biaxial loading. Stress Intensity Factors (SIFs) are determined using corrected Atluri-Kobayashi multiparameter stress field equation in conjunction with over-deterministic least squares method. The SIF values calculated are normalized with the SIF for a single crack and compared with finite element results. The comparison is found to be good. For a single central crack in a cruciform specimen, when the biaxial ratio is increased from 0 to 1, only shielding is observed. On the other hand, for two asymmetric cracks both amplification and shielding effects are seen that are dependent on the crack-tip under consideration, crack interaction angle and biaxiality ratio. Empirical relations to estimate the normalized SIF under different biaxial ratios are also given.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have