Displacement Correlation Technique for Interface Crack by FEM

Abstract

Interface crack is evaluated using modified quarter point crack tip displacement method. Quarter point elements around the crack tip were employed in the Finite Element (ABAQUS) analysis to determine the near crack tip grid point displacements. In this study, a technique is adopted in which the crack opening displacement of the near crack tip grid point is forced to satisfy a known constraint. The linear term in the distance around the crack tip is reduced to zero. The complex stress intensity factor for interface crack is determined using the quarter point and the displacement correlation technique. It is well observed that FEM produce a less reliable displacement approximation around interface crack tip. However, this report will show that the use of near crack tip open displacement as determined by the standard finite element method can be utilised to give satisfactory result for the interface stress intensity factors K1 and K2.