Failure analysis of a composite structural spar and rib-to-skin joints

• Published in: Procedia Structural Integrity 2024, Vol.54, p.490-497
• Main Authors: Skarka, Wojciech, Kumpati, Ramesh, Skarka, Michał
• Format: Article
• Language: English
• Subjects: separated by semicolons; Type your keywords here
• ISSN: 2452-3216; 2452-3216
• DOI: 10.1016/j.prostr.2024.01.111

The mechanical efficiency of a composite structure often depends on the strength of the joints that connect different parts to form a load path. Composite T-joints are commonly used in aerospace, marine, and civil engineering applications due to their lightweight and high strength properties. The complex stress distribution and geometric variations in these joints can lead to premature failure, careful attention is necessary in wing structures at skin-to-spar and skin-to-rib joints that are subjected to extreme load conditions. One type of structural joint is the composite sandwich with monolithic laminated material, which can offer significant advantages such as increasing material bending rigidity without adding considerable weight. Several approaches have been proposed to improve the performance of this joint and especially T-joints and reduce the risk of failure. These include optimizing the joint geometry and laminate stacking sequence, improving the manufacturing process, and using advanced materials such as nanocomposites and hybrid composites. However, the mechanical behaviour of this type of component has not yet been fully explored. This research aimed to study the modes of structural failure that include matrix cracking, fiber breakage, and interlaminar shear of these joints under tension, compression and shearing loads using the finite element method and verify the different designs of joints. The obtained numerical results were validated by experimental tests and the best results from compressive test are used for unmanned aerial vehicle structures especially integrated with solar panels.