LAUSR

Abstract In this paper, a new approach for evaluating the Stress Intensity Factors (SIFs) using the interaction integral method with correction terms for cracks in three-dimensional Functionally Graded Material (FGM) is presented. The present interaction integral method allows us to adopt finite element models consisting of only tetrahedral finite elements with unstructured mesh arrangements. The proposed interaction integral is tested by numerical examples, for the accuracies under mode I and mixed mode loadings and using unstructured finite element models consisting of tetrahedral finite elements only. The results maintained the so-called path-independent property of the interaction integral method while providing accurate results when compared with available analytical solutions.