Study on Dynamic Characteristics of a Curved Track Subjected to Harmonic Moving Loads.

Wheel-rail interaction in the curved track is a complex dynamic problem. It is important to make a model to research the dynamic characteristics of a curved railway track subjected to harmonic moving loads. The discretely supported curved Euler beam is used to simulate dynamic response of the curved track which is part of the circular structure whose cyclic length is the spacing of fasteners. Based on the dynamic characteristics of the periodic structure subjected to harmonic moving loads, the dynamic responses of a curved track can be solved within one basic element of the track. The analytical solutions of out-of-plane vibrations of a curved beam can be obtained by solving a system of linear equations with eight unknowns in the frequency domain. Several conclusions are obtained as follows. The significant frequency band of the dynamic responses of a curved beam is located around the load excitation frequency. With the increasing velocity of loads, the responses within a narrow band around the excitation frequency will be reduced, but responses of other frequencies will increase significantly. On both sides of the load excitation frequency, there are parametric excitations with a certain frequency spacing. With the increase of the load velocity, the maximum peak value of the track responses in time history caused by harmonic moving loads varies little, but the responses time will be shorter. [ABSTRACT FROM AUTHOR]