Date and place of thesis defense:
03.03.2006, Faculty of Mechanical Engineering
mr. sc. Elma Ekinović
prof. dr. Vlatko Doleček
Investigation of influence of a damage on the dynamic behaviour of beam-like structures
The results of investigation of the influence of damage on the dynamic behaviour, i.e. natural frequencies of transversal vibrations of beam-like structures are presented in this thesis. An original damage identification methodology based on bending frequency information before and after damage is established. The proposed method is one of the so-called model-based damage identification methods, which rely on theoretical or numerical model of the beam structure. The damage is simulated as a narrow open notch perpendicular to the beam axis. Natural frequencies are measured using the impact method. The identification of damage location and its depth is performed by use of regression relations between changes in natural frequencies and damage parameters, followed by a use of outlier extraction. The methodology is validated through simulated and experimental identifications of a number of damage scenarios.
Key words :
Natural frequency, damage, beam, identification, regression analysis