Structural Micro-Damage Identification

초록

Though there have been extensive theoretical and ex-perimental studies on the identification of structural damages, there are few studies on the small-sized baby damages such as the micro-damages. In this paper, the dynamic equation of motion for the beams with micro-damages is derived by introducing a damage distribution function. A damage identification method is then derived from the frequency response functions. The damage identification method can be used in several ways, de-pending on the choice of the exciting frequencies, vibra-tion response measuring points, and the damage detec-tion zones. The minimum number of vibration modes to be considered in the damage identification analysis is measured in order to lower the analysis error induced by the miss of high frequency modes far below the effects of micro-damages. Based on the present damage identi-fication method, a simple automatic damage searching method is developed. Numerical tests are conducted to verify the present damage identification theory and the automatic damage searching method.