Understanding Strength reduction in Aerospace Composites Structures: The Role of Delamination
Abrar H. BALUCH
Abstract. Composite materials possess excellent properties in terms of their high strength and stiffness. The use of CFRPs composites in aerospace and space applications is increasing exponentially due to their superior properties and usage in primary structures. Such structures because of their nature, if get impacted by external projectiles or debris can develop barely visible impact damage developing delamination within themselves. These delaminations become catastrophic when faced with additional compressive loads. These kinds of events are called compression after impact [CAI] events, and they are very critical for aerospace structures. These problems are solved by structural engineers either by experimentation or conducting computational studies by using commercially available tools or in-house developed codes. The experimental evaluation of CAI is quite expensive while the computational approach makes it a reasonable choice for engineers. In this study, the CAI event is computationally evaluated using commercially available ABAQUS software. Continuum shell modeling is utilized to make the geometry following the ASTM D7137 and Airbus AITM 1-0010 standard. Boundary conditions were provided according to the standard to mimic the failure behavior. Unidirectional AS4/8552 pre-preg material and its properties were used as material property. Structures with predefined delamination, which mimics impact events, were evaluated in this research and found that the simulated results were within ±10% difference, showing that Abaqus simulation helps researchers minimize experimental cost and can increase diversity in the profile of the results and composite laminates for CAI events. Local, mixed, and global buckling plays a critical role in CAI events.
Keywords
Compression After Impact, Delamination, Composite Structures, Low Velocity Impact
Published online 7/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Abrar H. BALUCH, Understanding Strength reduction in Aerospace Composites Structures: The Role of Delamination, Materials Research Proceedings, Vol. 69, pp 1204-1209, 2026
DOI: https://doi.org/10.21741/9781644904251-207
The article was published as article 207 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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