EXPERIMENTAL INVESTIGATION ON DEBONDING DAMAGE DETECTION OF HONEYCOMB SANDWICH CANTILEVER BEAM

Experimental investigations are performed on the damage detection for honeycomb sandwich composite beams by using a combined damage detection method. The debonding damages of the honeycomb sandwich beams are artificially induced in different positions. The combined detection method is incorporated with the correlation function amplitude vector (CorV) analysis and the continuous wavelet transform (CWT). Only the time domain vibration responses of the intact and damaged structures are required in the damage detection procedure. In the detection, the beam is excited with steady random excitation. CorV of the beam is calculated by using the measured vibration responses at all the measured points. Then these CorVs of intact and damaged beam are analyzed by biorthogonal continuous wavelet transform. The results demonstrate that the debonding damage of the structure can be identified by comparing wavelet coefficients of the intact and damaged structures. And the damage region can be located through the two maximum modulus of the difference of the coefficients obtained from intact and damaged structures.