Frequency-Response-Based Damage Localization Comparison by Time-Domain and Nonlinear Features in a Cantilever Beam

A vibration based damage detection framework for a cantilever beam under three structural conditions—healthy, initial crack, and extended crack—is investigated, focusing on measurable changes in the dynamic response associated with stiffness degradation. Frequency domain, time domain, and nonlinear dynamic analyses are used in combination to achieve this goal. Measurements of the frequency response function (FRF) are analyzed to identify changes in resonance behavior and evaluate damage using indicators based on improved correlation. In parallel, statistical feature analysis is used to process raw acceleration signals. The proposed multi-domain approach incorporates amplitude, distribution, and nonlinear complexity metrics, relying on assumptions of linear elastic behavior and sufficient sampling to resolve local changes. The results demonstrate clear and consistent distinctions among the three structural states. FRF based indicators capture stiffness reduction, while time domain statistical and nonlinear measures exhibit progressive trends with crack growth, indicating that combining multiple signal processing perspectives provides a robust basis for early crack detection in beam like structures.

کلیدواژه ها:

structural health monitoring ، vibration analysis ، damage detection ، FRF ، nonlinear dynamics