APPLICATION OF SMOOTH ORTHOGONAL DECOMPOSITION ON DAMAGE IDENTIFICATION

Resumo

This is an ongoing research in which a Structural Health Monitoring (SHM) methodology,
namely, the Smooth Orthogonal Decomposition (SOD), is employed on damage identification on beams.
In a first step, displacement data from the structure is subjected to a Spectrum Analysis Amplitude and the

most energetic vibration frequencies are acquired. Subsequently, SOD is applied to the same displace-
ment data in order to obtain the linear mode shapes and natural frequencies of the structure. Finally, most

energetic mode shapes are selected by correlation of frequencies obtained on the two previous steps. The
procedure is applied to both a damaged structure and a similar healthy one. Damage spot identification
is achieved by mode shapes comparison of healthy and damaged models. The technique is tested using
Finite Elements models for beams under two boundary conditions, namely, simply supported beams and
cantilevered beams. For each of the two case studies above, numerical models concerning damage in
different spots are generated for comparison. The results show that the method is successful aiming at
identifying structural damage. Robustness and limitations of this procedure are discussed.