عنوان مقاله [English]
This study focuses on the application of an interval type 2 fuzzy logic controller in an active tuned mass damper (ATMD) for the purpose of decreasing structural response under different types of earthquake excitation. One of the main shortcomings of type 1 fuzzy logic systems is their inability to consider uncertainty in the fuzzy rule base data. Type 2 fuzzy logic systems have the ability to handle this problem, and also take into account uncertainty in loading and structural behavior. To evaluate the efficiency of the proposed control method (interval type 2 fuzzy logic control method), a realistic eleven story shear building, located in Rasht City, Iran, was used. The active tuned mass damper (ATMD) is placed on the top floor of an eleven story shear building. This building has been analyzed under different time history records, including Hachinohe and El Centro earthquakes as far-field ground motions, and Kobe and Northridge earthquakes as near-field ground motions. The results obtained by the proposed control method were compared with those of the uncontrolled structure, the structure with the tuned mass damper (TMD) and the structure with the active tuned mass damper (ATMD) with a type 1 fuzzy logic controller. Numerical results indicated that the interval type 2 fuzzy logic controller used in the active tuned mass damper (ATMD) is very effective in reducing structural response under the effect of different base excitations. The comparison of time history responses for a type 1 fuzzy logic controller and an interval type 2 fuzzy logic controller also show that the displacement response obtained using an interval type 2 fuzzy logic controller is smaller and smoother than that obtained by a type 1 fuzzy logic controller. In view of the external control force needed to reduce the building response, the magnitude of the control force in the type 2 fuzzy logic controller is little more than that needed for the type 1 fuzzy logic controller with the average being about 8 percent.