Biaxial load effects on crack extension in anisotropic solids

The one-parameter singular expression for stresses and the corresponding displacements near a crack tip in anisotropic solids has been widely thought to be sufficiently accurate over a reasonable region for any geometry and loading conditions. In many cases, however subsequent terms of the series expansion are quantitatively significant, and hence we propose to consider the evaluation of such terms and their effect on the predicted crack growth direction. For this purpose the problem of horizontal-cracked orthotropic plate subjected to a biaxial loading is analyzed. It is assumed that the material is ideal homogeneous anisotropic. By considering the effect of the load applied parallel to the plans of the crack, the distribution of stresses and displacements at the crack tip is examined. In order to determine the direction of initial crack extension we employ the normal stress ratio criterion. The analysis is performed for a wide range of anisotropic material properties and applied loads. It is shown that the direction of crack extension can be seen to occur for nonzero values of theta (0) as the load parallel to the crack increases. (C) 2001 Elsevier Science Ltd. All rights reserved.