Vibrations of Railway Bridges

The paper contains a discussion of the nature of the approximately resonant vibrations of bridges due to the pulsating forces generated by unbalanced drivers, the influence of the motion of the train, and possible action of the springs; a group of proposed approximate formulas for predicting the natural frequencies of bridges, whether unloaded or supporting trains; a description of the methods of measuring natural frequencies; a list of the sources of damping; a theoretical demonstration of the effects of a small amount of distributed damping in restraining the forced vibration, and an appendix in which the frequency formulas are derived.