Analysis of Wheel-set Hunting under Vehicle-Bridge Dynamic Interaction

The characteristics of wheel-set hunting movement under vehicle-bridge dynamic interaction are studied in this paper. A vehicle-bridge interaction analysis model is established, which consists of a vehicle subsystem and a bridge subsystem, and the two subsystems are linked by the wheel-rail force definition with creep theory in lateral direction. The interacted system is excited by the track irregularities. The wheel-set hunting can be calculated from the lateral movement of wheel-set and bridge, and track irregularity. An inter-system iteration solution is used in calculation. As a case, the calculation process and the results of an SS8 locomotive with four wheel-sets passing a 10x32 m simply-supported beam bridge are studied, and the characteristics of wheel-set hunting with different train speed or different natural frequency of beam are compared and analyzed.