Power spectral density analysis for damage identification and location

A method for both identification and localization of structural damage is proposed and implemented on a simply supported beam. The results are predicted with an analytical model and verified with an experimental test set-up consisting of an aluminum beam with one actuator and one sensor, both piezoelectrics. The method estimates the energy localized in bandwidth regions near resonance that are the most sensitive to damage. The energy is estimated by power spectral density analysis and quantified by means of its root mean square value. These values are combined with mode shapes to locate damage. The method is evaluated with small masses used to simulate damage and or small cuts to simulate damage and good agreement is obtained between experiments and analysis.