A FINITE-ELEMENT ALTERNATING METHOD FOR 2-DIMENSIONAL MIXED-MODE CRACK CONFIGURATIONS

A finite-element alternating method (FEAM) is presented for two dimensional mixed-mode cracked problems. An analytical solution is presented for arbitrary polynomial normal and tangential pressure distributions applied to the crack faces of an embedded crack in an infinite plate. This analytical solution is used as the fundamental solution in the alternating method. For the numerical part of the method the finite-element method is used. For problems of edge cracks emanating from internal boundaries, the method is modified to account for the effect of fictitious crack tip. This modification, the origin-shifting method, is explained in detail. The FEAM is applied to a variety of mixed-mode crack problems with different configurations and loadings to assess the validity of the method. The method gave accurate stress-intensity factors with minimal computing effort. As the method needs to model only the uncracked body, finite-element models with large degrees of freedom are not required and therefore, the method has been implemented on personal computers. © 1990.