# Effects of Diagonal Friction Dampers on Behavior of a Building
## 5 Conclusions and Recommendations  
The results obtained as a result of our experimental and numerical studies using fifteen different friction damper configurations on a scaled model building are as follows:  
* In the 1-FD model, depending on the acceleration time histories of the earthquake records, the period value decreased by approximately 17% compared to the Reference building without a damper. This caused an increase of approximately 5% in the period value of the 5-FD building model. This evaluation shows that the dampers used on the lower floors affected the period properties of the building model more than the dampers used on the upper floors. * In the case where the damper was placed on the ground floor of the building (1-FD), there was at least a 32% reduction in peak displacement compared to the Reference model without the damper. In the case where we used a damper on the second floor of the building, there was a decrease of at least 24% in the displacement, and at least 6% in the case where dampers were used on the the third and fourth floors. The damper being on the top floor caused an increase of at least 2%. The obtained results show that placing the dampers on the lower floors was more effective for peak displacement. * The greatest reduction in roof displacement was obtained in the models where the dampers were placed close to the ground floors (1-2 FD and 1-3 FD). The reduction in displacement was lower in the 1-3-5 FD and Full-FD models than in these models. This result shows the importance of designing the dampers in sufficient quantity and with proper placement. * The stiffness of the floor where the dampers were located was increased, thus causing an increase in the earthquake load acting on that floor. Therefore, the roof displacement increased. The increase in displacement in the model in which the friction damper was placed on the top floor of the building (5-FD) confirms this result. * The reduction rates in roof displacement varied according to the earthquake record affecting the building. This result shows that the selection of the earthquake record in the design of friction dampers is important. * The maximum reduction in shear forces in the building columns was 51% when dampers were used (1-FD) on the first floor of the building, while it was 7% when dampers were used on the fifth floor of the building. Placing the dampers on the lower floors was more effective in reducing the column shear forces. * At the frequency corresponding to the building period, the variation in the floor shear force differed according to the spectral acceleration magnitude. Spectral acceleration shows that the damper had a smaller effect on the story shear force in large earthquakes and a greater effect in earthquakes with low spectral acceleration. Even if the ratio decreased, the effect of the damper in reducing the floor shear force was at least 50%. The dampers positively affected the floor where they were located the most, and the lower or upper floors. When the results are evaluated, it can be said that when a structure with friction dampers is designed, the position and number of dampers in the building are important in terms of seismic behavior. In order to minimize the roof displacement of the building and the internal forces on the structural elements, it has been determined that placing the dampers on the lower floors where the floor shear forces are high increases their efficacy. The decrease in the roof displacement of the building in the models with an increased number of dampers (1-3-5 FD and Full-FD) shows that the cost increases when the damper placement is not carried out properly. Methodology, E.A. and E.B. ; Software, M.G. ; Validation, M.G. ; Investigation, E.A., E.B. and M.G. ; Writing--original draft, E.A. and E.B. ; Visualization, E.A., E.B. and M.G. All authors have read and agreed to the published version of the manuscript. This research was funded by Sakarya University of Applied Sciences Scientific Research Projects Coordination, grant number: 016-2020. Not applicable.