چكيده به لاتين
Due to the political, economic and social importance of civil structures and the need to maintain their efficiency, structural health monitoring has become one of the challenges for researchers in the field of civil engineering. Correct and early detection of the probable damage can prevent catastrophic financial and human losses. The basic idea of the vibration-based damage detection is that a damage, which arises in the form of a local stiffness loss in the structure, alters its dynamics characteristics, i.e., natural frequencies, mode shapes and modal damping. Since damage in the structure is accompanied by a change in the dynamic characteristics of the structure, we can assume that the changes are based on the presence of damage. based on the assumed relationships between the input and output variables of the structure a series of models are defined To define the structural damages, which this method is called the model updating method. Finite element (FE) model updating is one of the ways to identify the structural damage. The purpose of FE model updating is to modify the dynamic parameters of the numerical model in order to obtain better agreement between numerical results and test data.metaheuristic algorithms can be used to optimize finite element models. In this study, the model updating method has been used to identify structural damages, a new objective function based on flexibility matrix and frequncy is presented and PSOGWO and PSOGSA Algorithms are used to optimize the FE model. To evaluate the performance of the proposed method, damage detection in three structures are studied. These cases include,a 2D-Truss structure with 25 elements, a 2D-frame structure with 27 elements and a 2D-Shear Frame structure with 15 stories. The results show that both algorithms by the proposed objective function work well in identifying the location and extent of damages.
