A strategy for the enrichment of experimental data as applied to an inverse eigensensitivity-based FE model updating method

Abstract

A strategy for the enrichment of experimental data is examined in connection with the problem of finite element model updating. The strategy is based on the simultaneous exploitation of the dynamic responses of various structural configurations, obtained by deliberate changes of the original boundary conditions, by grounding of one or several degrees of freedom. The main theoretical aspects of the methodology are first introduced, including the formulation of an updating method based on the inverse eigensensitivity of non-self-adjoint systems and also the basic formulation of a technique enabling the eigensolutions of more constrained structural configurations to be calculated from the frequency response functions of a less constrained configuration, so that additional tests can be avoided. Some numerical examples illustrating several key points of the methodology are presented. Through these examples, regarding the problem of localisation and correction of FE modeling errors, it is demonstrated that the proposed strategy enables an effective enlargement of the knowledge space of the structure, and can lead to improved results. © 1998 Academic Press Limited.