Analysis of influence factors of rail corrugation in small radius curve track

Abstract

In order to effectively prevent and control the generation and development of rail corrugation, according to the actual line condition of the small radius curve section, the vehicle (with flexible wheel sets)–track space coupled model was established by using the multi-body dynamic software UM (Universal Mechanism), which could consider the coupled relationship in three directions of space, and the dynamic analysis for the corrugation section was carried out by using the model. Then, based on the theory of friction self-excited vibration, the three-dimensional model of a wheel–rail system was established by using the finite-element software ABAQUS, and the complex eigenvalue analysis of influence factors of rail corrugation was conducted based on wheel–rail contact parameters obtained by dynamic calculation. Through the stability analysis of the wheel–rail system with different fastener vertical and lateral stiffnesses, friction coefficients, and superelevation states, we find that properly increasing the fastener vertical and lateral stiffnesses, controlling the wheel–rail friction coefficient below 0.4, and keeping the balanced superelevation state of the track structure can effectively reduce the occurrence possibility of unstable vibration of the wheel–rail system, thus inhibiting the generation and development of rail corrugation. The excess superelevation state of the track structure results in the unstable friction self-excited vibration of the wheel–rail system at the inner wheel–inner rail, while the deficient superelevation state results in the unstable friction self-excited vibration of the wheel–rail system at the outer wheel–outer rail, which shows that the superelevation state of the track structure directly affects the formation of rail corrugation and determines the development order of corrugation of inner and outer rails. This conclusion can well explain the cause of corrugation appearing on only one side rail.