Innovative Approaches for the Flaw-Tolerant Design and Certification of Airframe Components

A computational framework designed to enable reliable prediction of damage accumulation caused by cyclic loading in metallic airframe components containing small initial flaws, was developed under the Phase I project. The framework contains two novel features that are essential for meeting the objective of quantifying in-service damage with respect to fatigue criticality: (a) A family of predictors of damage accumulation were defined and calibrated in which the predictor is based on a weighted average of a function of stress and (b) the procedure developed for predicting quantities of interest meets the technical requirements of simulation governance. The proposed work is to perform fatigue life predictions at the component level; augment the functionality of the computational framework to include 3D surface topography scans of flaws as input, perform uncertainty quantification to provide probabilistic fatigue life predictions based on the models of damage accumulation; and facilitate the integration of the computational framework into the Probabilistic Damage Assessment Framework software.