Stress Singularity for a Crack with an Arbitrarily Curved Front
LEHIGH UNIV BETHLEHEM PA INST OF FRACTURE AND SOLID MECHANICS
Pagination or Media Count:
To investigate the possibility of a point of a crack front propagating in a direction not in the normal plane of the crack front, the three-dimensional form of the crack front stress field is obtained. To simplify comparisons of the states of stress at various points lying on a spherical surface centered at a point of the crack front, a local spherical coordinate system is used. It is found that the crack propagation will be from each point of the crack front in a direction lying in the normal plane. The results are used in conjunction with the strain energy density fracture criterion for the problem of an elliptical crack. The plane of the flat elliptical crack makes an arbitrary angle with the field of uniform applied tensile stress. Crack growth directions for various positoins along the crack front are determined, and loads required for fracture for various angles are obtained.