The seasonal-frozen layer may have an influence on embankment motion from train-induced vibrations. Based on the field monitoring in a seasonally-frozen region of northeastern China, the effects of the frozen layer on the embankment responses to train-induced vibration were investigated in winter and summer via acceleration time histories and acceleration frequency spectrums. The results show that: (1) Compared to unfrozen soil conditions, the amplitudes of longitudinal and vertical vibrations at the points near the rail were increased, different influences of freight versus high-speed trains are the most evident. (2) With greater distance from the rail, the dominant frequency ranges of embankment with both frozen and unfrozen layers narrowed and shifted to low frequency bands. (3) The predominant frequency of embankment vibration with frozen soil layers shifted to higher frequencies with the increased train speed, although there was little change with unfrozen condition. Layer condition (frozen versus unfrozen) and distance to rail both play important roles in investigating the embankment vibration characteristics and rail transit field monitoring to improve the criterion of the rail construction in seasonally-frozen regions.
