ON DESIGN METHODS FOR BOLTED JOINTS IN COMPOSITE AIRCRAFT STRUCTURES

The problems related to the determination of the load distribution in a multi-row fastener joint using the finite element method are discuss ed. Both simple and more advanced design methods used at Saab Military Aircraft are presented. The stress distributions obtained with an ana lytically based method and an FE-based method are compared. Results fr om failure predictions with a simple analytically based method and the more advanced FE-based method of multi-fastener tension and shear loa ded test specimens are compared with experiments. Finally, complicatin g factors such as three-dimensional effects caused by secondary bendin g and fastener bending are discussed and suggestions for future resear ch are given.