AN ANTI-RESONANCE TECHNIQUE FOR DETECTING STRUCTURAL DAMAGE

摘要

In the resonance method for detecting structural damage, natural frequencies are identified from spectrum peaks and compared with the frequencies of the previously undamaged structure. In that way, one can quickly determine whether the structure is defective or not. However, in order to determine the approximate location of the defect, a lot of post-measurement processing is required. An alternative technique based on anti-resonance frequencies is presented. Resonance frequencies, being global in nature, do not change in magnitude from one point of measurement to another, unlike anti-resonance frequencies which exhibit significant variations, depending on the location of the measurement site. By exploiting this characteristic, the approximate location of certain kinds of defects in a structure may be obtained more rapidly if the anti-resonance technique is used.