结构损伤识别的柔度灵敏度方法

Damage Identification by the Sensitivity Analysis of Structural Flexibility

提出了结构损伤识别的柔度灵敏度方法。首先根据Neumann级数展开来推导结构柔度矩阵关于单元刚度损伤参数的灵敏度公式,以此为基础建立结构的损伤识别方程,通过矩阵拉直运算将矩阵方程转化为线性方程组来求解各单元损伤参数。指出了柔度矩阵灵敏度方法优于特征对灵敏度方法的几个显著特点。最后用一个桁架结构模型对所提方法作了验证。

Structural damage identification based on the sensitivity technique of structural flexibility is studied. Using the Neumann series expansion, the flexibility sensitivity of the structure is firstly derived to obtain the damage detection equation. Then all the elemental damage parameters can be easily calculated by manipulating the matrix equation into a set of linear equations. Two significant advantages of the proposed flexibility sensitivity method are pointed out. The first one is that the computation of structural flexibility sensitivity is very simple and then the presented method is easily to implement. The second one is that the number of independent linear equations of the proposed method is greater than that of the previous eigenparameter sensitivity technique in most case. So damage detection results obtained by the proposed scheme will be more accurate than that obtained by the eigenparameter perturbation method. A 31 -bar structure is used as a numerical example to validate the presented flexibility sensitivity method and the results are satisfactory even if noise is present. It has been shown that the proposed approach is more effective than the eigenparameter sensitivity technique and may be a promising method for structural damage detection.