Assessment of seismic behavior of buildings retrofitted with self-centering dampers based on non-linear dynamic analysis

In traditional methods of seismic design, structures have been designed on the basis that members remain elastic under weak earthquake while they exceed elastic zone under severe earthquakes, but the method of the modern design criteria, structure performance (i.e. displacement,…) has been defined as the basis of design instead of using member forces. In other words performance design has been replaced strength design. Self-centering dampers (SCd) are such dampers which show no residual deformation. They are capable of recovering their original shapes after the removal of external forces. These dampers represent moderate energy dissipating capacity and consist of re-centering components group and an energy dissipating components group. Residual drift is an important index for structure's damages so using these dampers (that vanish residual drift) decrease damage of structures. In this research the impact of self-centering devices on seismic performance of steel frames has investigated. For this purpose a five story building has modeled in OpenSees software with and without self-centering device, each structure has analyzed using nonlinear time history analysis with considering 3 earthquake records.Results show that SCd would eliminates residual drift as well as decreasing in maximum drift of each story. So we could conclude that SCd increase the structure's performance.