Assessment of different finite element modeling techniques on delamination growth in advanced composite structures

Uçak, İbrahim
Virtual crack closure technique (VCCT) is commonly used to analyze debonding/delamination onset and growth in fiber reinforced composite assemblies. VCCT is a computational fracture mechanics based approach, and is based on Irwin’s crack closure integral. In this study, the debonding/delamination onset and growth potential in a bonded fiber reinforced composite skin-flange assembly is investigated using the VCCT. A parametric finite element analyses is conducted. The finite element analyses results are compared with coupon level experimental results available in the literature. The effects of different finite element modeling techniques are investigated. The bonded flange-assembly is modeled with pure solid (3D) elements, plane stress (2D) shell elements and plane strain (2D) shell elements. In addition, mesh density, element order and geometric non-linearity parameters are investigated as well. The accuracy and performance of these different modeling techniques are assessed. Finally, effect of initial defect location on delamination growth potential is investigated. The results presented in this study are expected to provide an insight to practicing engineers in the aerospace industry.


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Citation Formats
İ. Uçak, “Assessment of different finite element modeling techniques on delamination growth in advanced composite structures,” M.S. - Master of Science, Middle East Technical University, 2012.