基于移动附加质量的损伤诊断技术

Damage diagnosis based on natural frequencies of a structure by adding known masses

基于结构固有频率的损伤诊断技术能够识别结构的损伤程度,但是识别损伤位置较为困难。结合环境激励模态试验方法和动力修改理论,提出了基于移动附加质量的损伤识别技术。通过对损伤与完好结构施加系列已知附加质量,根据损伤与完好结构施加附加质量后的固有频率识别结构损伤。计算结果表明,当频率满足识别精度要求时,该方法能够较准确地识别损伤结构的损伤位置。

The damage level can be estimated with natural frequencies of a structure,but it's difficult to estimate the damage location,especially,the symmetric position of the damage.Combining the theory of dynamic modification and the modal experimental method with ambient excitation,an innovative damage diagnosis methodology was developed based on moving additional masses.By adding a series of known masses to the damaged structure and the undamaged one,the variation of the natural frequencies of the two mass-modified systems was employed to identify the structural damage.Numerical examples indicated that this method can estimate the damage location accurately when the natural frequencies of the damaged sturcture satisfies the requirements of identification accuracy.