The Effect of the Cut on the Power Spectral Density of the Beam

Cracks are one of the causes of the decline in the bearing capacity of beams. Crack studies often use the natural frequencies as a parameter to identify the occurrence and growth of cracks. However, for a small crack, the natural frequency does not change significantly, and thus, it is not useful for the early damage identification. In this study, the shape change of the power spectral density (PSD) is proposed as a novel feature more sensitive to cracking. This feature is represented by the centroids of the PSD (C-PSD) of the beam under moving load with different levels of cuts.