Structural damage identification based on power spectral density sensitivity analysis of dynamic responses

• Damage identification based on the power spectral density sensitivity analysis is proposed.
• Response and its power spectral density sensitivity are calculated from the random excitation.
• Local damages can identified accurately from the power spectral density of a few measurement points.

A new method is proposed to identify locations and severities of structural damages based on the power spectral density sensitivity analysis. Firstly, the structural responses and power spectral density under stationary and random excitations are calculated using pseudo excitation method. Then, the sensitivities of power spectral density with respect to the structural damage parameters are obtained. Finally, the finite element model updating method is adopted to identify the structural damages from the calculated and the simulated measured power spectral density. Two numerical examples demonstrate the satisfactory identification results obtained from the present method.