Detection of Fatigue Cracks in Flexible Geometrically Non-Linear Bars by Vibration Monitoring

Vibration-Based Diagnostics of Fatigue Damage of Beam-Like Structures

“…From expression (7) with the boundary conditions in equation (4) the functions describing the angle of rotation GH (x), bending moment M GH (x) and transverse force Q GH (x) can be derived. The boundary conditions at the clamped end (x"0) and free end (x"¸) of the beam and conditions of compatibility of sections 1 and 2 (x"¸A) will be [10] …”

“…These methods are based on the relationships between the vibration characteristics (natural frequencies [1}3] and mode shapes [4]) or peculiarities of a non-linear vibration system behaviour (for example, non-linear distortions of the displacement wave in di!erent cross-sections of a beam [5,6], the amplitudes of sub-resonance and super-resonance vibrations [7], the anti-resonance frequencies [8], etc.) and damage parameters.…”

An Analytical Approach to Determining the Dynamic Characteristics of a Cylindrical Shell With Closing Cracks

“…Of note are the papers of Tsyfansky and Beresnevich [18] and Staszewski and Worden [19] in which the damage detection in construction elements has been considered.…”

Non-Linear Vibration Method for Detection of Fatigue Cracks in Aircraft Wings

“…High-sensitivity super-resonant vibration methods for crack detection in beam-type structural elements are proposed in references [7,8]. These methods can be developed on the assumption of piece-wise linear crack elastic characteristic with a bend at the origin of the co-ordinates.…”