The Challenge - Commercially available crack growth software tools such as AFGROW are indispensable to damage tolerance analysts. AFGROW has two key attributes that have led to its widespread adoption by the structural analysis community: a friendly GUI and versatility. However, analysts are often required to make compromises because real crack scenarios are not exactly the same as those provided in AFGROW, which results in uncertainty in the crack growth analysis. AP/ES was tasked by AFGROW developers to create a method for expanding the database of crack scenarios in AFGROW while still preserving its user friendliness.

Engineered Solution - AP/ES employed Microsoft COM technology to integrate an external K-solver with AFGROW. The external K-solver chosen to demonstrate the concepts was the p-version finite element software StressCheck© (ESRD, Inc., St. Louis, MO). This integrated software suite makes boundless the universe of available crack scenarios and produces accurate and reliable stress intensity solutions. The external K-solver can be deployed in one of several modes depending on complexity of the required crack scenario: interactive plug-in, handbook plug-in, or tabular look-up.