Model Updating Strategy for Structures with Localised Nonlinearities using Frequency Response Measurements

X Wang, TL Hill, SA Neild (Bristol University), AD Shaw, H Haddad Khodaparast & MI Friswell (Swansea University)

Mechanical Systems and Signal Processing, Vol. 100, 1 February 2018, pp. 940-961

Abstract

This paper proposes a model updating strategy for localised nonlinear structures. It utilises an initial finite-element (FE) model of the structure and primary harmonic response data taken from low and high amplitude excitations. The underlying linear part of the FE model is first updated using low-amplitude test data with established techniques. Then, using this linear FE model, the nonlinear elements are localised, characterised, and quantified with primary harmonic response data measured under stepped-sine or swept-sine excitations. Finally, the resulting model is validated by comparing the analytical predictions with both the measured responses used in the updating and with additional test data. The proposed strategy is applied to a clamped beam with a nonlinear mechanism and good agreements between the analytical predictions and measured responses are achieved. Discussions on issues of damping estimation and dealing with data from amplitude-varying force input in the updating process are also provided.

Paper Availability

This material has been published in the Mechanical Systems and Signal Processing, Vol. 100, 1 February 2018, pp. 940-961, the only definitive repository of the content that has been certified and accepted after peer review. Copyright and all rights therein are retained by Elsevier.


Link to paper using doi: 10.1016/j.ymssp.2017.08.004

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