基于小波变换的海洋平台结构损伤检测(英文)

Damage Detection for Offshore Platform by Wavelet Transform

基于结构动力特性的海洋工程结构损伤检测是一个非常有工程应用价值的研究课题。特别是对于海洋平台水线以下的结构损伤,一般通过结构的频率、振型和频响函数等的变化用来发现损伤。但是对于早期的损伤(通常损伤量很小),上述结构动力特性参数的变化可能很小从而不足以反映结构的这种早期微小损伤。文章提出采用小波变换的方法来进行小损伤的检测,将结构的频响函数(FRF)和加速度响应进行小波变换,很好地预报了损伤的存在。文中还以某海洋平台为例,进行了模型试验,从而验证了提出方法的可行性。

Damage detection in offshore structures using the dynamic parameters is becoming an important research topic.Parameters such as frequencies,modal shapes and frequency response function（FRF） are used to detect the damage.When some damage in the underwater structure occurs,these dynamic parameters of the structure will change.The shift of the parameters can be used to identify the damage,the location and even the damage magnitude.The damage at different locations can make the parameters change differently.However early damage（usually very small） can only slightly change such parameters.Wavelet transform can be employed to detect the subtle shift of the parameter.This paper aims to use the wavelet transform for the FRF and acceleration response history to detect the small damage.The model test is carried out to verify the proposed method.