DAMAGE DETECTION FOR RETICULATED STRUCTURES BASED ON SPECTRUM ENERGY OF FREQUENCY RESPONSE FUNCTION

Reticulated structures are often applied in large scaled public facility, whose failure will lead to heavy losses. Identification of damage zone will facilitate significantly damage diagnosis. The concept of spectrum energy of frequency response function was proposed in this paper based on spectrum energy of acceleration response. Spectrum energy of acceleration response under white noise excitation can be reconstructed with frequency response function, thus nodes spectrum energy of frequency response function can be obtained. Geometrical characteristic index for energy distribution surface was defined; whose value can indicate, to some extent, damage degree. The proposed method does not require natural frequencies and mode shapes as input parameters. Numerical analysis of a reticulated structure demonstrated the feasibility of the method proposed. ‘Symmetry effect’ was observed in damage detection.