Optimal Nonlinear Energy Sinks in Vibration Mitigation of the Beams Traversed by Successive Moving Loads

Optimal Nonlinear Energy Sink (NES) is employed in vibration suppression of the beams subjected to successive moving loads in this paper. As a real application, a typical railway bridge is dynamically modeled by a single-span beam and a traveling high-speed train is simulated by a series of successive moving loads. Genetic algorithm is employed as the optimization technique and optimal parameters of the NES system are accordingly obtained. It is found that the NES can remarkably suppress the vibration level particularly in vicinity of the critical speeds. A sensitivity analysis is then carried out and robustness of the optimal NES is investigated. A parametric study is performed and performance of the optimal NES is evaluated for different values of the load speeds, load magnitudes, load intervals and mass ratios.