Stress intensity factors of square cracks in one-layered transversely isotropic halfspaces subject to internal expansion or tensile traction

Abstract

This paper studies the stress intensity factors of square cracks horizontally placed in one-layered transversely isotropic halfspaces using the dual boundary element method (DBEM). This DBEM uses the point load fundamental solution of a transversely isotropic bi-material fullspace. On the uncracked boundary, the infinite boundary elements are used to consider the influence of the domain far from the crack. On the crack surface, special crack-front elements are introduced to capture the crack-tip behavior. The relative crack opening displacements on the crack surface are treated as unknown quantities. The crack opening displacements near the crack tip are used to calculate the stress intensity factors. Numerical results illustrate that the proposed method can obtain highly accurate results of the three stress intensity factors for the crack problems in one-layered transversely isotropic halfspaces. The square cracks in homogeneous or bi-material halfspaces under internal expansion or tensile traction are analyzed in detail. Results show that the material anisotropy of transversely isotropic materials exerts a strong influence on the stress intensity factors.