Interval-based identification of response-critical joints: A tool for model refinement

To accurately model the dynamics of a complex built-up structure it is often necessary to forgo the assumption of ideal rigid coupling between components. The dynamic behaviour of inter-component connections, or joints, can have a significant impact on the performance, even survivability, of an assembled structure. For complex structures, where many joints are present, the complete characterisation and/or modelling of all joints is often not feasible. Hence, in the development or refinement of a component-based model there is a need to identify the response-critical joints of an assembly — those joints whose refinement would benefit the modelling effort most. In the present paper we address this issue by considering a ‘possibilistic’ interval-based assessment of joint variability, and propose a sensitivity metric to rank order joints based on their influence towards the dynamics of the assembled structure. Results are compared against local gradient-based and global sampling-based metrics as part of two numerical examples.