路基冻胀对高速列车-轨道耦合系统动力特性的影响

在车轨耦合动力学理论的基础上,通过对高速列车-无砟轨道-路基耦合系统模型有限元进行分析,研究高速铁路路基不均匀冻胀对列车、轨道的动力学影响,分析不同条件下冻胀变形引起的系统振动响应规律,进而提出相关改善措施以利于系统良性发展.结果表明,路基不均匀冻胀会引起列车与轨道产生互相影响的动态响应,降低了轨道结构的服役性能,同时不利于行车安全.在典型冻胀情况下,列车进入冻胀区域后,在起始位置受到振动所造成的影响比较大;随着路基冻胀波长的增加,对车体的振动影响相继减少,而冻胀峰值的影响则相反.对冻胀波长25 m范围内,特别是10～15 m路基冻胀进行整治,可增强行车安全性和乘坐的舒适性.同时,重点控制路基高冻胀峰值能有效减少轨道结构的疲劳损伤.

Analysis of influence of roadbed frost heave on dynamic characteristics of high-speed train-track structure coupling system

Based on the theory of vehicle track coupling dynamics, through the finite element analysis of the coupling system model of high-speed train-ballastless track-subgrade, this paper studies the dynamic influence of uneven frost heave of high-speed railway subgrade on the train and track, analyzes the system vibration response law caused by frost heave deformation under different conditions, and then puts forward relevant improvement measures to facilitate the benign development of the system. The results show that the uneven frost heaving of the subgrade will cause the dynamic response of the train and the track, reduce the service performance of the track structure, and is not conducive to the traffic safety. In the typical case of frost heaving, when the train enters into the frost heaving area, the impact caused by the vibration at the initial position is relatively large; with the increase of the frost heaving wavelength of the subgrade, the impact on the vibration of the vehicle body decreases successively, while the impact of the frost heaving peak is the opposite. The improvement of frost heave in the range of 25m, especially in the range of 10m to 15m, can enhance the driving safety and riding comfort. At the same time, focusing on controlling the peak value of Subgrade Frost Heaving can effectively reduce the fatigue damage of track structure.