Working Group 1: Generation of validated structural dynamic models - results of a benchmark study utilising the GARTEUR SM-AG19 test-bed

In practice the validation of analytical structural dynamic models is mainly based on comparing experimental modal analysis results with the analytical predictions. Despite the high sophistication of analytical (Finite Element) modelling, practical applications often reveal considerable discrepancies between analytical and test results. In recent years significant effort has therefore been expended on the development of mathematical procedures for updating analytical mass and stiffness matrices using dynamic test data. The success of these methods is governed not only by the skill of the analyst to assume an appropriate initial analysis model but also the source and the location of the erroneous parameters to be corrected. In practical applications the source and location of the errors can be manifold, resulting in non-unique updated models with all of them fulfilling the mathematical criterion of minimising the test/analysis discrepancies. The aim of the present benchmark study defined within the European COST Action F3 on “Structural Dynamics� was not only to compare the different computational model updating (CMU) procedures using a common test structure. The aim was also to see if the expected non-uniqueness of the results due to different computational methods, different structural idealisations and different parameter sets and, of course, different test data sets can be tolerated with regard to the intended utilisation. The participants were allowed to generate any initial finite element model that they found suitable. That finite element model with the lowest model order and best fulfilling the given criteria should be considered the optimum model.