Investigation of base shear in the steel structure with rotational friction damper influenced by the soil-structure interaction

Rotational friction dampers (RFDs) have been proposed as one of the passive control tools in order to increase the seismic performance and lateral control of structures and the loss of input energy of earthquakes through friction in their rotating plates.  Apply of the rotational friction dampers will reduce shear stress and improve the dynamic response of the structures. In the nonlinear analysis and design of structures, the underlying soil is usually assumed to be rigid, if the flexibility effect of the structure bed is used, the dynamic characteristics of the structures will be different. Examining the behavior of structures by considering the effects of soil and structure interaction can give us a more accurate understanding of the behavior of structures, and this is while in most of the designed structures, the effects of soil stiffness and possible elevation of the foundation is not considered.  In this article, a typical ten-story building is considered and in it, with type two hard soil and type three soft soil, the performance of the damper with different damping capacity and interaction effect was analyzed with SAP 2000 software. Shear stress in different floors of the structure was analyzed in four cases: with dampers and with the effect of soil interaction and with dampers without the effect of soil interaction, without dampers with the effect of soil interaction, and without dampers and without the effect of soil interaction. The graphs showed how much the rotational friction damper can be useful in reducing the shear in different floors of the building, taking into account the effect of soil and structure interaction. Three earthquake records were utilized for this research and at the end, the results were compared with each other. The results indicated that the use of rotational friction dampers reduced the shear in all cases and the analysis of the sliding load of the damper and the required capacity of the structure were also obtained.