Title: Progressive Failure Analysis for Predicting Ultimate and Residual Strength of Composite Bonded Repairs

Authors: John Lin, Michael Fleming, Mohamed Azdamou, Erick Espinar-Mick, Reewanshu Chadha, John Bakuckas

DOI: 10.33599/nasampe/s.24.0272

Abstract: The Boeing Company and the Federal Aviation Administration (FAA) have been investigating the safety and structural integrity of bonded repairs since 2007. Recent efforts have been focused on testing and analyzing bonded repairs to carbon fiber reinforced composite panels representative of transport category aircraft structure, by using the Aircraft Beam Structural Test (ABST) fixture, an innovative structural test capability at the FAA William J. Hughes Technical Center and state-of-the-art analysis methods. Fail-safety of bonded repair and repair for primary structure made from emerging materials such as Thermoplastic Composite are the two most recent research areas. This paper will cover application of Finite Element Analysis (FEA) based Progressive Failure Analysis (PFA) for strength prediction of intact and failed composite bonded repairs. Fundamental PFA theories and key material parameters will be reviewed, along with simulation results for carbon fiber reinforced thermoset and thermoplastic composite repair panels under tension. All analysis results showed good correlation with test data in both failure load and failure mode, providing an economic way for exploring repair options without expensive physical testing. Guidelines and lessons-learned will be presented at the end.

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Conference: SAMPE 2024

Publication Date: 2024/05/20

SKU: TP24-0000000272

Pages: 14

Price: $28.00