Vertical vibrations of a multi-span beam steel bridge induced by a superfast passenger train

Transient and quasi-steady-state vertical vibrations of a multi-span beam steel bridge locatedon a single-track railway line are considered, induced by a superfast passenger train, moving at speed120-360 km/h. Matrix dynamic equations of motion of a simplified model of the system are formulatedpartly in the implicit form. A recurrent-iterative algorithm for solving these equations is presented.Excessive vibrations of the system in the resonant zones are reduced effectively with passive dynamicabsorbers, tuned to the first mode of a single bridge span. The dynamic analysis has been performed for aseries of types of bridges with span lengths of 10 to 30 m, and with parameters closed to multi-spanbeam railway bridges erected in the second half of the 20 th century.