Introduction of a new metallic-yielding pistonic damper for seismic control of structures

Abstract

A new damper with pistonic performance is presented in this research for seismic control of structures. A set of rectangular metallic yielding plates has been considered as the energy dissipating part for this device. The damper is configured in such a way that can provide the loading conditions as pure-bending for this part during cyclic motions. This configuration makes the damper to have an optimized flexural yielding mechanism and consequently a high-level of force capacity and damping ratio. The dissipator part is placed into a steel surrounding rigid box which has only one sliding translational degree of freedom along its longitudinal axis. Accordingly, the device can perform as a tension/compression piston with sufficient stability in other directions. The proposed metallic-yielding pistonic (MYP) damper can be used in various types of structural systems such as moment-resisting or braced frames and even coupled shear wall systems with the capability of dual or multiple-installation in each frame bay. In this research the hysteresis behavior of this damper has been numerically investigated. Then as a parametric study, the effects of various MYP design parameters on the damper hysteretic behavior were studied. Finally, the control performance of this device was seismically investigated in a one-story moment-resisting frame considering possible beam flange out-of-square imperfections. According to observed results, the proposed damping system is high-performance in seismic structural protection at low-value story drifts. Besides, it was able to significantly reduce the structural responses and residual deformations as well as the out-of-plane frame motions.