Experimental study of track nonlinear energy sinks for dynamic response reduction

A track nonlinear energy sink (NES) is a type of vibration mitigation device that is capable of reducing the response of a primary structure for a broad range of input frequencies. In this paper, the equations of motion of the track NES system are derived and then an optimized design and the experimental realization of the track NES are described. Subsequently, the performance of the track NES is examined experimentally when implemented in a two-degree-of-freedom model building structure subjected to impulsive and seismic excitations. A comparison of the experimental results and numerical simulations serves to demonstrate the validity of the derived model of the track NES system. Additionally, comparisons between the experimental responses of the primary structure with the unlocked and locked track NES show that the track NES can rapidly attenuate the response of the primary structure. This attenuation is shown to occurs, in part, due to the track NES facilitating the transfer of energy from lower modes to higher modes, where the response can be dissipated at a faster rate.