To seek the generation and development mechanism of rail corrugation, the relationship between track support stiffness change of the rail system and wheel-rail system dynamic receptance is investigated. The mechanism of "variation of difference between wheel and rail receptance" has been studied recently as one of the main reasons to cause the short wavelength rail corrugation. It can clearly describe the basis of rail corrugation generation. Based on this new understanding, reduction in the variation difference of wheel-rail receptance and rail vibration in the lateral direction can effectively prevent the formation and development of rail corrugation. The effects of rail deflection and lateral vibration on the rail corrugation development have been demonstrated with two types of rail fasteners with different lateral stiffnesses on a curved track. Rail roughness levels have been monitored using the CAT system every month for a period of the rail grinding circle under normal traffic condition. A new resilient baseplate system, with a similar vertical stiffness but high lateral stiffness relative to the Egg baseplate, was installed and compared with the existing Egg system on an curved track with radius of 350 m on Nanjing Metro Line 1 in order to compare rail corrugation development of two systems. It is concluded that one of the key means to slow down the corrugation growth is to reduce the difference of wheel-rail receptance and control the rail dynamic deflection and vibration level in the lateral direction. Rail roughness growth on the track with Egg baseplate is about 15 dB(A) higher than that on the track with the high lateral stiffness resilient baseplate in about 6 months period after the rail was ground.
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