Özet
The use of changes in dynamic system characteristics to detect damage has received considerable attention during the last years. Within this context, FE model updating technique, which belongs to the class of inverse problems in classical mechanics, is used to detect, locate and quantify damage. In this study, a sensitivity-based finite element (FE) model updating scheme using a trust region algorithm is developed and implemented in a complex structure. A damage scenario is applied on the structure in which the stiffness values of the beam elements close to the beam-column joints are decreased by stiffness reduction factors. A worst case and complex damage pattern is assumed such that the stiffnesses of adjacent elements are decreased by substantially different stiffness reduction factors. The objective of the model updating is to minimize the differences between the eigenfrequency and eigenmodes residuals. The updating parameters of the structure are the stiffness reduction factors. The changes of these parameters are determined iteratively by solving a nonlinear constrained optimization problem. The FE model updating algorithm is also tested in the presence of two levels of noise in simulated measurements. In all three cases, the updated MAC values are above 99% and the relative eigenfrequency differences improve substantially after model updating. In cases without noise and with moderate levels of noise; detection, localization and quantification of damage are successfully accomplished. In the case with substantially noisy measurements, detection and localization of damage are successfully realized. Damage quantification is also promising in the presence of high noise as the algorithm can still predict 18 out of 24 damage parameters relatively accurately in that case.
Orijinal dil | İngilizce |
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Sayfa (başlangıç-bitiş) | 211-225 |
Sayfa sayısı | 15 |
Dergi | Journal of Sound and Vibration |
Hacim | 305 |
Basın numarası | 1-2 |
DOI'lar | |
Yayın durumu | Yayınlandı - 7 Ağu 2007 |
Finansman
The present research is carried out in the framework of OMAX (Operational Modal Analysis in presence of eXogeneous inputs) project, supported by the Flemish National Fund for Scientific Research. Pelin Gundes Bakir was a postdoctoral fellow of the Flemish National Fund for Scientific Research- Belgium (FWO-Flanders) at the Katholieke Universiteit Leuven between years 2003 and 2006, during which this research was conducted.
Finansörler | Finansör numarası |
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Flemish National Fund for Scientific Research |