Investigation of the Effect of using Viscous Dampers on the Seismic Performance of Steel Flexural Frames under the Effect of Seismic Sequence Phenomenon in the Near-Fault Area

Due to the seismicity of Iran and the occurrence of irreparable human and financial losses during the past years and in order to reduce these losses due to lateral loads, control methods can be used. Vibration control is a low-cost method among various methods of improving the seismic behavior of structures, which leads to a reduction in the response of the structure under dynamic loads. Control systems are divided into four categories: inactive, active, semi-active and combined. In this research, for the accuracy of modeling, an analytical article conducted by other researchers is used and the results are compared. Then 6 frames without damper and 6 frames with viscous damper with the same number of floors, under the title of short level 3, 5, medium level 7, 10 and high level 12, 15 floors in Itbus software according to 360-AISC- regulations, sixth and tenth topic National building regulations are loaded, designed and controlled. The results show an increase and improvement in the performance of the structure with a viscous damper compared to a normal structure. Reducing the displacement of floors can help reduce issues such as the seam allowance of two buildings as well as the comfort of residents in the event of an earthquake. Reducing floor drift can help improve the behavior of non-structural components and joinery. The presence of viscous dampers has reduced the displacement and drift of floors by even 90%. The presence of a viscous damper makes the drift of the floors more uniform. The presence of a viscous damper reduces the forces applied to the members and increases the capacity of the structure. As a general conclusion, the use of viscous dampers has acceptable results in structural responses and has increased the behavior and capacity of the structure.