Behavior of ground vibrations induced by trains moving on embankments with rail roughness

This study investigates the behavior of ground vibrations induced by trains moving on embankments using theoretical formulations, finite element analyses, and field experiments. The train-induced vibrations are large at the dominant frequencies of nV/L_c, even though the rail is very rough, where n is a positive integer, V is the train speed, and L_c is the carriage interval. For subsonic train speeds, the train-induced ground vibration is extremely small when the rail is perfectly smooth, but with a minor rail irregularity, the train-induced ground vibration can be significantly increased. However, for supersonic train speeds, the ground vibrations with or without rail irregularities are not very different, and the vibration of the first dominant frequency having the longest wavelength is the most obvious wave.