Formation Mechanism of Rail Corrugation on Curved Track : 2nd Report, Basic Formation Mechanism

Abstract

We successfully reached the formation mechanism of corrugation by full scale stand tests, commercial line experiments and theoretical simulation. From these works, we conclude that main causes of corrugation formation are the large creepage between wheel and rail, and periodical change of vertical force on wheel/rail contact surface. That is, the corrugation is caused by: 1) excessively large creepage between wheel and rail, which is caused by insufficient rolling radius difference between inner-outer wheels or large attack angle between wheel and rail; 2) oscillation of vertical contact force between wheel and rail, which is caused by the vertical vibration including Hertian contact stiffness or the rail tilting vibration; 3) stick-slip between wheel and rail accompanying with the vertical contact force oscillating. The frequency of corrugation is decided by vertical contact force oscillation.