Reduction of railway bridge vibration with groundhook mass damper

The aim of this research is to compare eff ectiveness of an ordinary mass damper with a more complex one equipped with an extra spring element connecting the damper mass with the ground. For both simple- and nonlinear- primary structure models and for stable load state, theoretically effi ciency of both types of dampers is just the same therefore their effi ciencies in bridge structures subjected to non-stationary load are investigated.