Repair Tolerance Analysis for Composite Structures Using Probabilistic Methodologies

摘要

During operational service, composite structures in aircraft are inspected at predetermined intervals. If damage is detected, engineers refer to the structural repair manual to determine appropriate repair procedures, which ensures safety. But there is little information on that whether the existed repair policy is the most cost effective. In this paper, a concept called repair tolerance is proposed by defining two critical thresholds, when to repair and when to replace, to address both safety and economic issues. A simulation procedure was developed to model the operational lifecycle of the structural strength considering impact damage. A probabilistic approach was applied to optimize the two thresholds in repair tolerance by assessing the probability of failure as well as minimizing the total maintenance cost. This method can be used by aircraft manufacturers and operators to support their decision-making for an optimized repair policy.