A SIMPLE TECHNIQUE FOR ESTIMATION OF MIXED MODE (Ⅰ/Ⅱ) STRESS INTENSITY FACTORS

摘要

A simple and efficient finite element based technique using the crack face nodal displacements for the accurate estimation of mode I, mode II and mixed mode I/II stress intensity factors (SIF) is proposed in this paper. Finite element (FE) method is used to obtain the crack face nodal displacements of various cracked configurations. Convergence studies are conducted. The estimated SIFs are compared with the other techniques such as displacement extrapolation, J-integral, and interaction integral techniques, along with the published results. Results indicate that the proposed technique is found to be simple and provides accurate SIF even for the relatively coarser meshes. Results also indicate that the accuracy of the proposed technique is of the order of the path independent integrals in a given mesh. Further, the proposed technique also evaluates the sign of mode II SIF, K-II, which is vital in fatigue crack growth simulations.