Short Tutorial on Fracture Mechanics

A working knowledge of fracture mechanics is vital to an engineer because of its various applications to structural design. Fracture mechanics can be used to:

• Determine how large a crack can be in a structural member before it leads to catastrophic failure

• Predict the rate at which a crack can approach a critical size due to fatigue loads or aggressive environmental conditions

• Determine the direction of growth of a rapidly propagating crack, and to ascertain the appropriate conditions under which the crack will stop growing

Crack-flaws cannot be neglected in engineering analysis; even microscopic crack flaws can grow over time, ultimately resulting in fractured components. Structures that may have been blindly deemed "safe" could fail disastrously, causing injuries to its users, or in the grimmest of cases, causing the loss of life. The following are two case examples of engineering fracture-failures.