Preliminary Study on Superharmonic Resonance Phenomena Caused by Nonlinear Wheel-Rail Contact Interaction in Metro Transit

This paper proposes to use the principle of "Superharmonic Resonance" in theory of nonlinear vibration to explain a common frequency peak phenomenon in field tests of metro environmental vibration. Based on the theory of FMBD (Flexible Multi-Body Dynamics), a complex "vehicle-track-tunnel" model was constructed with help of Universal Mechanism software. Both flexibilities of railway track structures and nonlinear contact characteristics between the wheel and rail pairs have been taken into account, the Park method was used to solve stiff DAEs. Superharmonic resonance phenomena of wheel- rail forces and accelerations of substructure have been carried out numerically as expected. The principle can be not only used for analysis of environmental vibration, but also for study of out-of-round wheel as well as rail corrugation problems.