Numerical and experimental studies on a new metallic-yielding pistonic damper based on pure-bending flexural yielding mechanism

Abstract

In this study, the numerical and experimental investigations of a new passive control system recently introduced by the authors are discussed. This system is a metallic-yielding pistonic damper (MYP) in which the lateral excitation is transferred to a set of rectangular metallic-yielding plates under pure-bending loading conditions. The dissipator plates are placed into a steel surrounding rigid box which has only one sliding translational degree of freedom along its longitudinal axis. Based on this configuration, the damper performs as a piston-like axial element under cyclic motions. In this study first, the conceptual design and theoretical basis of the proposed system are presented and then, the details of the MYP numerical and experimental program are discussed. For this purpose, the MYP stability and performance are examined by conducting displacement-control cyclic tests on 12 physical specimens as well as finite element analyses on the corresponding numerical models. According to obtained results, the specimens experiencing ductility values from 15 to 38 during the tests, exhibit a broad range of ultimate capacity from 23 to 245 kN. Overall, the damper is found to have nonlinear behavior with consistent strain hardening and preserve its stability and performance during a large number of consecutive cyclic motions. Moreover, it was found that the MYP control system supplies high levels of damping ratios at low values of the lateral story drift due to its fuse-like performance.