ABSTRACT
Sudden fracture of structures fabricated from low-strength structural steels has been reported from the beginning of the 20th century. Gas, water, oil, and molasses tanks were fractured causing human casualties and extensive material losses. The term brittle here means fracture with no permanent deformation and a consumption of little energy. The analytical development of fracture mechanics has been known in the literature as 'Linear-Elastic Fracture Mechanics' (LEFM). In the 1920s Griffith observed that as the length of an individual glass rod decreases as a rescue of successive tensile failures, the tensile strength increases in the remaining portions. The stress distribution at the tip of a crack is found by examining the solution for a stress concentration problem around an elliptical hole by considering the crack as an ellipse with a minor axis of zero length. The bulk of fracture mechanics literature is mainly concerned with the first mode of crack deformation.
