Experimental Design of the K-Damper Device for Attenuating Vibrations in Structural Applications

Abstract

The mitigation of mechanical vibrations forms an important and challenging pursuit of practical significance for ensuring the safety and resilience of engineered systems. Recently emerging solutions exploiting negative stiffness characteristics have been shown to deliver potent towards vibration mitigation. This work studies, in particular, the vibration mitigation potential of the K-Damper, a negative stiffness device here explored for structural protection of frame structures. In an experimental setting, a physical model of a 3- storey frame is created with the attenuation device deployed at the base of the structure. The resulting geometrically nonlinear behaviour is exploited for the realization of a negative stiffness mechanism, effectuated by means of a space-efficient mounting configuration. Shaking table tests are performed under harmonic inputs and seismic excitation, with the performance of the system cross-assessed against the non-retrofitted structure. We report on the efficacy of the K-Damper device in mitigating vibrations under two-dimensional base excitation, revealing significant vibration reduction, both in terms of accelerations and inter-storey drifts, showing potential towards practical applications.