An Interval Based Technique for FE Model Updating

Model updating techniques are largely used in civil and mechanical engineering to obtain reliable FE models. The model parameters are iteratively adjusted until the model response matches the measured structural response within a given tolerance. The task is made difficult by the uncertainty that affects both the structural response and the model parameters. In this work, the uncertainty is taken into account by a proper formulation of the problem in the framework of interval analysis. Uncertainty is replaced by interval numbers, functions are replaced by their thin or thick natural extension and the inclusion theorem is exploited to find the problem solution. Sample applications are illustrated using a modal representation of the structure. A numerical example is used to discuss the potential of the proposed method. A case study is solved to demonstrate the advantages of the method with respect to conventional updating techniques.