Effect of response type and excitation frequency range on the structural damage detection method using correlation functions of vibration responses

In previous paper by the authors, the inner product vector (IPV) was proposed as a damage detection algorithm which uses cross correlation functions between vibration responses under band pass white noise excitation. As the characteristics of IPVs calculated by different vibration responses (i.e. displacement, velocity and acceleration) under band pass white noise excitation with different frequency range should be different, the effectiveness of the damage detection method may be affected by the response type and excitation frequency range. This paper just investigates the effect of response type and excitation frequency range on the IPV-based structural damage detection method. Firstly, the theoretical formulae of IPVs and the damage index using IPV are reviewed shortly. Then, the effect of response type on the IPVs is analyzed based on the characteristics of the theoretical formulae of IPVs, and the principle for choosing the response type for calculating IPV under band pass white noise excitation with different frequency range is proposed as well. Finally, simulative damage detection examples of a shear frame structure are presented to illustrate the theory and method proposed in this paper.

► We investigate the effect of response type on the IPV method.
► We investigate the effect of excitation frequency range on the IPV method.
► Displacement IPV and velocity IPV are dominated by lower order modes.
► Acceleration IPV might feature many modes of the structure.
► Modes that best reveal the potential damage locations should be included in the IPV.