Identification of damage in beam and plate structures using parameter dependent modal changes and thermographic methods
The present chapter is concerned with the damage identification based on modal analysis and thermographic method.
The shift in the free frequency spectrum is considered and the additional parameter is introduced to the structure in order to increase the sensitivity to damage effect, for instance elastic or rigid support, and mass rigidly or elastically attached to a structure. The proper damage indices are introduced and their variation indicates damage location. The identification problem is next treated for a beam structure. The sensitivity analysis of free frequencies and associated modes is treated in detail and some approximate methods are discussed.
The second part of chapter is devoted to identification problem by means of measured boundary temperature in a steady-state heat conduction problem. The inverse problem is constructed by minimizing the properly defined distance norm of measured and model temperatures. The proper sensitivities of introduced identification functional with respect to translation, rotation and scale change of defect are calculated using a new class of path-dependent sensitivity integrals. Several numerical examples for a disk with a single crack-like cutout illustrate the presented approach.
KeywordsCantilever Beam Damage Index Plate Structure Damage Identification Support Position
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