MODEL UPDATING IN STRUCTURAL DYNAMICS: A GENERALISED REFERENCE BASIS APPROACH

Abstract The paper considers the problem of updating an analytical model from experimental data using the reference basis approach. In this general framework, certain parameters, e.g. natural frequencies or modeshapes, are considered to be completely accurate and the others are updated by solving a constrained optimization problem. The main results are closed-form solutions to reported problems with general weighting matrices in the optimisation criterion. The importance of this generalisation, in addition to its theoretical value, is the ability to incorporate prior knowledge regarding the accuracy of the model in specified areas into the method. This paper investigates also the geometrical interpretation of the results, providing an insight into the mechanism of the updating process. The advantages of the new updating schemes are demonstrated by means of examples.