Response Modification Factor of Steel Structures Equipped with Cylindrical Frictional Dampers

Frictional dampers are widely used in civil engineering structures as means of passive control in order to dissipate the energy created by earthquake. One of the frictional dampers that have been recently introduced is called Cylindrical Frictional Damper (CFD). Several researches in the area of the energy absorption capacity of the CFD, meaning hysteretic behavior, have been performed by the authors.
In this research, response modification factor of steel moment resisting frames equipped with Cylindrical Frictional Dampers is evaluated. Utilizing this factor, the standard seismic design code procedure can be applied to the frames equipped with CFDs. In order to achieve this task, Static pushover analysis, nonlinear incremental dynamic analysis and linear dynamic analysis of various structures have been performed.
The results show that the response modification factor of steel frames equipped with frictional dampers is greater than that of conventional steel frames which in turns reduce the seismic forces and leads to a lighter structure. Finally, values of 11 and 16 have been suggested for ultimate limit state and allowable stress design methods respectively.