The wheel/track impact due to irregularities, such as wheel/rail roughness, track stiffness transition, bad welds and wheel flats is a major reason for the necessity of maintenance and causes environmental issues of the wheel/rail system, including rolling contact fatigue, sleeper cracking, ballasted track deterioration, rolling/impact noise and ground vibration. The maximum frequency of interest of the wheel/track impact is about 1kHz for ballasted track deterioration and 5kHz for noise. A review is presented on the characteristics of the wheel/track impact, dynamic behaviors of railpad and ballast, and non-linear vehicle/track interaction computer models used to predict noise and ballasted track deterioration. A resilient wheel and a combined rail track system are also introduced as promising candidates to mitigate the wheel/track impact.

Copyright (c) 2003 Railway Technical Research Institute