Sources of variability in metro train-induced vibration

In previous in-situ measurements of metro trains it has been found that the velocity level on track or tunnel wall may vary significantly between different train passages, even though measuring section, type and conditions are identical. An investigation is carried out into sources this variability, using a 3D train-track numerical model. This built software SIMPACK ABAQUS, connected through one-way coupling to finite element model soil. These models used study influence various parameters, including wheel rail unevenness, speed degree loading. For comparison, were made dynamic response wall. The roughness at site as well unevenness all 48 wheels for one measured. results from indicate affects in frequency region 25 250 Hz vibration above 5 Hz. can by up 20 dB due with largest variations occurring bands 50–63 Variations passenger loading affect train-induced 4.5 dB, mainly low region. When varies within range ±20% relative nominal 60 km/h, frequencies peaks shifted some change much 10 dB. However, unevenness. It concluded variation these especially should be considered achieve reliable predictions vibration.