基于应变模态曲率差的木梁损伤识别

Damage Identification of Wooden Beams Based on Strain Modal Curvature Differences

为了识别木梁截面的残缺,提出基于应变模态曲率差的木梁损伤识别方法。首先,采用ABAQUS建立完好木梁和不同程度损伤木梁的有限元模型并进行模态分析;然后,分别采用应变模态和应变模态曲率差的损伤识别指标对木梁进行损伤定位识别,通过拟合应变模态曲率差与损伤程度的关系式估算木梁的损伤程度;最后,通过木梁试验验证该指标的有效性。结果表明:应变模态损伤识别指标对木梁的截面损伤定位效果较差;应变模态曲率差指标具有较强敏感性,能够准确地识别出木梁损伤位置和程度。

This paper presents a damage identification approach based on the difference in curvature of strain modes to identify the defects of the cross-section of wooden beams.First,modal analysis was performed to establish the finite element models of both intact and damaged wooden beams using ABAQUS.Next,the damage identification indicators of strain mode and strain mode curvature difference were used to locate and identify the damage of the wooden beams,and the damage degree of the wooden beams was estimated by fitting the relationship between strain mode curvature difference and damage degree.Lastly,the wooden beams test was used to confirm the validity of the indexes.The results reveal that:the strain mode damage identification index is unsatisfactory for damage localization of wooden beams;the strain mode curvature difference index has strong sensitivity and can properly identify different damage and degrees locations of wooden beams.