Indirect structure damage identification with the information of the vertical and rotational mode shapes

The present study aims to propose a robust method to detect the damage severity and location of the structural elements, focusing on the data type and acquisition method and promoting the model updating tools. The novelty of this method lies in its rotational mode shape acquisition that provides valuable information on the damage. In this method, the damaged elements were indirectly identified by detecting the healthy elements and eliminating them from the search space. Moreover, this method could minimize the modal strain energy difference between the damaged reference model and the numerical model using an optimization algorithm. An improved genetic algorithm was then employed to perform the optimization task. In this study, four numerical and two experimental damage scenarios were applied to a simply supported beam to examine the performance of the proposed method. Data acquisition systems were implemented using vision-based and accelerometer-based methods. The results indicated that this method could accurately identify the location and severity of damage using only the first mode shape since the rotational mode shapes were more sensitive to damage than the vertical mode shapes.