Abstract
This paper proposes a new analytical model to investigate the three-dimensional elastic vibration of railway vehicles subjected to the excitation from vertical track irregularities. This mathematical model is compact with some hundreds of degree of freedom and can easily be modified for different vehicles. In this method, the carbody is modeled as a box-type structure consisting of plates and beams. The condition to connect components is satisfied by introducing artificial springs at their joints. By this treatment, it is possible to consider the effect of connecting rigidity between structures. The truck model includes the effect of the excitation input via traction devices and anti-yaw dampers in addition to the inputs through air springs directly from vertical track irregularities. This paper describes the formulation procedure of the method in detail. The eigenmodes and frequency response to vertical track irregularities are analyzed. The numerical results are compared with the measured data for an actual railway vehicle to examine the validity of the method. It is shown that the new model can express the complicated vibration modes observed in the actual railway vehicle, and the frequency response obtained by the method shows good agreement with measurements in the region of 0.5-20Hz.
