چكيده به لاتين
Abstract:
Damage detection is one of the subcategories of the health monitoring methods which has attracted much attention recently. Today the researches on damage detection methods, based on dynamic responses, have developed because they can be used as the time-to-event continual methods to prevent more damages. In this research a new three- step method is represented to detect the damages in multiple-member and large scale structures like structural frames.
Damages in structures change the static and dynamic characteristics of the structured and as the result of these changes, the location and severity of the damages can be identified. For large-scale structures, local damages may cause illegible changes in total modal characteristics of the structures which make more difficulties to identify local damages. Increasing of the internal data can decrease accuracy of the metaheuristic algorithms to specify the location and severity of damages.
To solve recent problems which mentioned above, in this research, the substructuring method is used to separate the original structure to independent substructures in order to decrease the search space and increase the sensitivity of the responses to damages.
The second step after separating the main structure to independent substructures, is determination of damage index of each element by using of Modal Strain Energy Based Index and identify the location of damages.
In the third step, by using damage index, based on differences between actual damaged structure and analytical model, as an objective function for cuckoo algorithm, the severity of damages is specified in structural elements.
To evaluate the proposed method, different examples are examined. The results indicate that the represented three-steps method can identified the location and severity of damages, even if there are multiple damages in the studied structures. As well as indicating that the result of cuckoo algorithm in these examples, is more accurate than other algorithms which are used in this research.
Keywords: damage detection, cuckoo optimization algorithm, substructure, Modal Strain Energy, location and severity of damage.
