Advanced composite structures require the integration of innovative load introductions tominimize manufacturing costs and weight. Therefore composite load introduction fittingsfunction as enablers to implement highly integrated structures. Design rules and feasible designsolutions are developed for these innovative fittings. These designs have two crucial aspects. Thefirst aspect concentrates on the load introduced into the fittings, which can be accomplished byeither bearing lugs (e.g. vertical tail plane attachment) or force introduction loops (e.g. helicopterrotor blade attachment). The second design aspect considers the load transfer from the loadintroduction to the attached structure inside the fitting. Hereby high out of plane laminateloadings can occur, which have to be considered. Therefore reliable and robust analysis methodsare needed to design these innovative fittings. An overview of different analytical as well asnumerical analysis approaches is given. Based on linear and non-linear finite element (FE)analysis methods, modelling aspects regarding the element type, load application, loadintroduction design, preferred fibre architecture, loading condition and bearing friction arediscussed. The diverse approaches are compared to different static and dynamic tests on coupon,subcomponents and full scale level for a validation of the design methodologies.
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