Damage detection using spatially incomplete frequency response functions

Abstract

A damage detection technique based upon an incompletely measured experimental model is studied. Conventional methods such as force balance method are effective to detect damage locations as long as the initial finite element model is accurate and the responses at all the degrees of freedom can be measured experimentally. But these two conditions are practically impossible to be met, with the exception of geometrically simple structures. This work suggests a damage detection method not utilising an accurate analytical finite element model but based upon incompletely measured frequency responses, noting that the reduced dynamical system is an inverse of incompletely measured frequency responses. This work also discusses frequency regions where the suggested method works satisfactorily. From both numeric and test examples, it is found that the proposed method can be an alternative to conventional damage detection methods. (C) 2003 Published by Elsevier Science Ltd.