Cracks and flaws occur in many structures and components for several reasons. The material may be inherently defective. Cracks may be introduced during the manufacturing stage, or later as a result of environmental conditions. The presence of such cracks or flaws can significantly degrade the structural integrity of a component under the action of applied loads and environmental conditions.

Fracture mechanics uses concepts from applied mechanics to develop an understanding of the stress and deformation fields around a crack tip when a crack is present in a structure. A sound knowledge of these stress and deformation fields helps in developing fail-safe and safe-life designs for structures. Such fracture-mechanics-based design concepts are widely used, but are not limited to, the fields of nuclear, aerospace, civil, and mechanical engineering.