Multiple damage identification in beams using continuous wavelet transforms

The paper focuses on detecting, locating and quantifying the damage occurring in three different forms, namely (a) a beam with only a dominant crack, (b) a uniformly degraded beam, and (c) a uniformly degraded beam with a dominant crack. Generalised methodologies have been proposed to solve the three damage cases. Fixed beams have been considered to demonstrate the effectiveness of the generalised method for damage identification. The beam is loaded with a point load. The static deflection has been used as the response to perform continuous wavelet transform (CWT). The continuous wavelet transform coefficients are used to compute the Holder exponent and an Intensity factor. The intensity factor is used to relate the damage (crack damage and/or degradation) characteristics to the magnitude of the wavelet coefficients. The proposed generalised method can be used to solve the damage identification problem for all fixed beams, irrespective of changes in the magnitude of load applied, geometrical and material properties. The effectiveness of the proposed method is demonstrated by validating with several numerical examples available in the literature.