基于静力残余力向量的结构损伤评估方法

残余力向量法是一类常用的损伤识别方法,现有的残余力向量法都是基于动力测试的模态参数,和动力测试数据相比,静力测试数据往往精度更高,且无需模态分析等复杂操作.鉴于此,本文提出一种静力残余力向量法用于结构损伤评估.所提方法利用静力测试位移数据,并结合结构有限元模型的刚度矩阵,定义了静力残余力向量,根据该向量中不为零的元素来判断损伤自由度,再根据自由度和单元之间的对应关系来确定发生损伤的位置,并进一步提出一种求解损伤参数的代数解法.另外,针对实践中角位移难以测量的情况,进一步提出了一种静力缩聚残余力向量法,拓宽了所提方法的应用范围.以桁架结构和梁结构模型为例对所提方法进行了验证,数值算例结果说明所提方法合理有效.

Structural damage assessment based on static residual force vector

The residual force vector method is a kind of commonly used damage identification method.The existing residual force vector method is based on the modal parameters of a dynamic test.Compared with the dynamic test data, the static test data often have higher accuracy and do not need complex operations such as modal analysis.In view of this, this paper presents a static residual force vector method for structural damage assessment.Based on the static displacement data and the stiffness matrix of structural finite element model, the static residual force vector is defined and the damage degrees of freedom are evaluated according to the non-zero elements in the vector.Then the position of the damage can be determined according to the relationship between the degrees of freedom and the elements.Moreover, an algebraic solution to the damage parameters is also proposed in this work.In addition, a static condensation residual force vector method is further developed to overcome the difficulty of measuring the angular degrees of freedom.The proposed method is verified by a truss structure and a beam structure model.The numerical results show that the proposed method is reasonable and effective.