FRF 계측데이터의 통계수정에 의한 휨부재의 손상탐지에 관한 연구

초록

This work presents an analytical method for detecting damage of flexural beam member without the baseline data at intact state. Based on the statistical process of FRF (frequency response function) data collected in the neighborhood of the resonance frequency, the damage of the beam member is considered. Normalizing the FRF data set collected at each nodal point, and extracting their mean values and the central difference approximation, the curvature of the mean values can be obtained. It can be observed that the damage exists at the region to represent the abrupt change of the curvature. The proposed method is rarely affected by the external noise and its level. It is exhibited that the FRF data in the region of the first resonance frequency can be utilized more effectively rather than the ones in the second resonance frequency. The validity of the proposed method is illustrated in a numerical experiment of beam model.

키워드