结构损伤识别的直接解析法

探讨一种损伤识别的方法——直接解析法.本方法从结构模态有限元算式出发,把频率和振型看作损伤参数的函数,经过泰勒展开获得频率、振型对损伤参数的一阶偏导数,然后构造以损伤参数为未知量的超定线代方程组,求解得到全部损伤参数值.进一步又提出本方法的自迭代修正,大幅度提高了识别精度.本方法可以同时识别出结构损伤的数量、位置和程度,并可识别任意多数量的损伤参数.通过对一个5层框架结构的数值模拟分析,验证了它的可行性.

Directly Analytical Method for Structural Damage Identification

This paper presents a direct analyzing method of structural identification. With the frequency and mode shape being regarded as functions of damage parameters, the overdetermined algebraic equations with damage parameters as unknowns can then be constructed by differentiating frequency and mode function on the basis of structure mode finite element formula, the damage parameters of which are obtained via Taylor expansion. The whole damage parameters can be found via solving the algebraic equations. Furthermore, the iteration-self modification is proposed to improve the accuracy of damage identification greatly. The present method can diagnose the number, the locations and the severity of the damage as well as the number of damage parameters without limit. A numerical simulation example of a five-storey RC frame structure is given to verify the feasibility of the present method.