基于曲率模态和小波变换的木梁损伤识别

Wooden beam damage identification based on curvature mode and wavelet transform

为解决曲率模态指标对结构小损伤识别的局限性,提出了一种基于曲率模态和小波变换相结合的结构损伤识别方法。以简支木梁为研究对象,采用ANSYS建立木梁损伤前后有限元模型并进行模态分析,对木梁损伤前后的曲率模态进行离散小波变换得到小波系数差指标;根据小波系数差突变峰值判断木梁的损伤位置,通过拟合小波系数差与损伤程度的关系式估算木梁的损伤程度,并由木梁试验对该指标进行了验证。结果表明:小波系数差指标可以准确识别木梁的损伤位置,通过拟合小波系数差指标与损伤程度的关系式来定量估算木梁的损伤程度。该研究成果为木梁损伤识别提供了理论依据。

To address the limitations of curvature mode indicators in identifying minor structural damage,a method for structural damage identification that combines curvature mode and wavelet transform has been proposed.In this paper,ANSYS was used to establish a finite element model of the wooden beam before and after the damage and carry out modal analysis,and the curvature modes of the wooden beam before and after the damage was subjected to discrete wavelet transform to obtain the wavelet coefficient difference index.the damage location of the wooden beam was judged according to the peak of the wavelet coefficient difference mutation,and the damage degree of the wooden beam was estimated by fitting the relationship between the wavelet coefficient difference and the damage degree.The wooden beam test verified the index.The results show that the wavelet coefficient difference index can accurately identify the damaged location of wooden beams.The damage degree of wooden beams can be quantitatively estimated by fitting the relationship between the wavelet coefficient difference index and the damage degree.The research results provide a theoretical basis for wooden beam damage identification.