Analytical and Numerical Investigation of Multi-fastener Joints in Composite Structures

Kurzfassung

In this study, the reaction forces arising in multi-fastener joints subject to different forms of in-plane loading are investigated. Different approaches are considered with the goal of designing a tool capable of predicting fastener loads in the context of early preliminary joint design. A review of the relevant literature on the topic is provided. The analytical models retained from the literature, as well as models modified or proposed as part of the study, are presented and discussed. The models accounting for the deformation of both the connected members and of the fasteners are based on a one-dimensional discretization of the joint through linear springs. The stiffness of the fasteners is calculated with empirically based methods. The applicability of the analytical models to joint design is assessed both in terms of accuracy and conservatism. The limits of validity of the assumptions underlying the analytical models are evaluated through comparison with detailed numerical models. Through 3D Finite Element analysis with linear material deformation, the parts composing the joint and their interactions are modelled. Joint design guidelines stemming from the findings of the numerical and analytical investigations are suggested.