Damage Detection Based on Modal Parameters and Dynamic Responses using by Enhanced Grey Wolf Optimization

Structural damage causes a reduction in stiffness of some elements of structure and gives rise to some changes in structures' modal parameters (natural frequencies, mode shapes, etc.) and dynamic responses (acceleration, velocity, and displacement). Hence, intact structures' data is different from damaged structures' data and can be used to detect structural damages. Many techniques are recently utilized to facilitate damage detection, some salient examples of which are non-destructive methods and using of structure responses. The main purpose of this paper is to present a method for estimating structural damage detection based on the measurement of modal parameters and comparing its results with results of measurement of dynamic responses in a limited number of degrees of freedom. To detect the damage, two objective functions have been defined: one with modal parameters and the other one with structural dynamic responses data. For optimizing the objective functions, a new hybrid algorithm including GWO and PSO has been designed and its results have been compared to GA and PSO. Two examples including a ten-story shear building and a ten-element truss are considered and the efficiency of the proposed strategy in damage detection is assessed. The results indicate that the proposed strategy has acceptable performance.