Research On Container Carbody Based On The Coupled Dynamic Characteristics

Container transportation as a fast, safe mode of transportation has become the main mode of transport of goods. During the decades of years, the maximum running speed has been 120km/h, the maximum axle load has arrived 25t and the light weight of the load bearing structure has been improving. With the running speed improvement, the track excitation frequency increases, while the influence of the light weight car’s stiffness characteristics on the dynamic performance has been increasing. Traditionally, the car body is viewed as rigid body in the vehicle system dynamics analysis, so the elastic body vibration characteristics and the corresponding respond influenced by the track excitation are ignored. Therefore the stiffhess characteristics should be considered, and the influence on the vehicle system dynamics should be analyzed.Based on the 60ft container flat car, the mode and frequency of the bound beam structure and the boundless beam structure is obtained by the finite element method. Then imported in the dynamic analysis modal, the rigid-flexible coupling model is built, the vertical vibration acceleration of the stiffness and flexible car body in different load methods in irregularity tack. The vertical vibration acceleration of different areas is earned on the FFT to obtain the PSD to analyze the vertical vibration characteristics in different stiffness car body. The results shows, in axially symmetric load the first order vertical bending vibration modal has a great influence on the middle of car body and the second order vertical bending vibration modal has a certain influence on the middle of car body, and in asymmetric load the second order vertical bending vibration modal has a certain influence on the head and the middle of car body.Based on GB/T 5599-1985 and UIC-518, the different body, the different loading ways of the multi-rigid-body dynamics model and the rigid-flexible coupling model are analyzed. The vertical stability analysis results shows:the vertical bending stiffness of car body have a great influence to the vertical stability index of straight line, embodied in the vertical bending stiffness increased, the vertical stability of straight line take a turn for the better. For the symmetry load case, the first order vertical bending vibration modal has a great influence on the stability of the middle of car body, the second order vertical bending vibration modal has great influence on the stability indexes of the head of car body; For the asymmetry load case, the first order vertical bending vibration modal has a certain influence on the stability indexes of the middle of car body, the second order vertical bending vibration modal has a great influence on the stability indexes of the head and the middle of car bodyIn the curve passing security analysis, the results show that there is little influence on curve passing security when introducing vertical bending modal; There is little influence on lateral wheel track forces and lateral wheel interaction forces when introducing torsion bending modal, but it has a certain influence to vertical wheel track forces, derailment coeffient and rate of wheel load reduction; when the torsion stiffness increased, the curve passing security got worse.