Advertisement
Published in:
2020 | OriginalPaper | Chapter
The Application of Spatial Filtration for Damage Detection in Structures with Multiple Poles
Author : Krzysztof Mendrok
Published in: Proceedings of the 13th International Conference on Damage Assessment of Structures
Publisher: Springer Singapore
Activate our intelligent search to find suitable subject content or patents.
Select sections of text to find matching patents with Artificial Intelligence. powered by
Select sections of text to find additional relevant content using AI-assisted search. powered by
Abstract
For many years, modal analysis and its results has been used to detect and locate damage. Also modal filtration, which is related to modal analysis, was recently applied for this purposes. Especially the method, which involves the detection of peaks that appear on the badly filtered output characteristics of the spatial filter. This poor filtration results from the fact that the spatial filter is tuned for the object in the reference (undamaged) state, and the filtered characteristics are recorded on the structure in the current (possibly damaged) state. Modal filter coefficients are the coordinates of a reciprocal modal vector which main property is orthogonality for all modal vectors except the one for which filter has been set. When the damage occurs, the modal vectors change, and the orthogonality of the reciprocal modal vector ceases to occur. Then the modal filter does not work properly. There are therefore additional peaks on the filtered characteristics and their presence is a symptom of damage.
The question arises how the method will work for the system, which contained double or multiple poles. In such a case, badly filtered peaks could be located at the same frequency as the main peak resulting from the natural frequency to which the filter was set. This can lead to failure in damage detection. Therefore, appropriate simulations have been carried out, the results of which will be presented in the article.