Multiple-criterion method for determining structural damage

A multiple criterion updating method which minimizes the Euclidean norm of the error vector obtained by adding the normalized eigenproblem equation and equation of motion with equal weighting functions is proposed. The method is applied to detecting damage in structures and is tested on an unsymmetrical H-shaped structure. It is found that the multiple criterion updating method predicts the presence, the position and the extent of damage. The multiple criterion method is compared to the frequency response function method and the modal property based method by using the co-ordinate modal assurance criterion and the modal assurance criterion. It is found that the proposed method gives results that are on average consistent with the results given by the two methods individually. Furthermore, it is postulated that the method gives an updated model which has a higher probability of being unique then using when the individual methods are used.