Vibration suppression of Timoshenko beams subjected to moving loads using an inertial nonlinear energy sink

Abstract

The dynamics of beams subjected to moving loads are of practical importance since the responses caused by these loads can be greater than those under equivalent static loads in some cases. In this work, a novel inertial nonlinear energy sink (NES) is applied for the first time to achieve vibration suppression in beams under moving loads. Based on the Timoshenko beam theory, the nonlinear motion equations of a beam with an inertial NES are derived using the energy method and Lagrange equations. The Newmark-β method combined with the Heaviside step function is adopted to calculate the responses of the beam under moving loads of constant amplitude and harmonic excitation. The accuracy of the modelling derivation and solution methodology are validated through comparisons with results from other studies. The results demonstrate that the velocity and excitation frequency of the moving load significantly affect the response of the beam as well as the performance of the inertial NES. To enhance its effectiveness under various moving load conditions, parametric optimization is numerically performed. The optimized inertial NES can achieve good performance by efficiently reducing the maximum deflection of the beam. The findings of this study contribute to advancing the understanding and application of NESs in mitigating structural vibrations caused by moving loads.