Effect of lateral undulatory support stiffness of rail on initiation and evolution of rail corrugation

A model of rail corrugation calculation is put forward. The model considers a combination of a theory of wheel/rail in rolling contact, an undulatory wear model of rail material and a dynamical performance of railway vehicle coupled with a curved track. A computer code for rail corrugation is developed, and the model is verified with a full scale test facility. The effects of the uneven lateral support stiffness of rail, due to discrete sleeper support, and the different curving speed of the vehicle on the initiation and development of rail corrugation are numerically investigated in detail. In the calculation the damage on the running surface of rail, concerning rail corrugation formation, is restricted to wear mechanism of rail material. Through the numerical analysis it is found that: (1) The uneven lateral support stiffness of rail, due to discrete sleeper support, easily causes the initiation and development of rail corrugation; (2) The corrugation mainly contains the same wave-length as a sleeper bay and 28~35 mm wave-lengths. The undulatory wear with 28~35 mm wave-lengths and very small depth trough is caused by a contact vibration of the wheel and rail at high frequencies; (3) The distribution of the maximum depth of undulatory wears on the rails under the 4 wheels of the same bogie is different; (4) The change of the curving speeds doesn't decrease the growth of the rail corrugation caused by the discrete sleeper support.