青藏铁路列车行驶引起的轨枕竖向作用力研究

摘要

为了深入分析列车行驶引起冻土场地的振动反应,并为青藏铁路运营安全性评价提供可靠的理论依据,采用自编列车-轨道耦合动力学仿真程序,研究了青藏铁路列车行驶引起的轨枕竖向作用力特性.研究表明：自编程序仿真结果与青藏铁路现场监测成果吻合良好,程序理论正确结论可信;轨枕竖向作用力随路基阻尼的增大而略微减小,随路基模量、列车行驶速度的增大而增大,随轨缝的增宽而线性增大;轨枕竖向作用力优势频段主要在移动轴重作用率内,转向架作用率处振动能量最大,轨枕振动对轨枕竖向作用力影响较小;路基的冻融状态、轨缝宽度与列车行驶速度对轨%In order to survey the vibration response of permafrost subgrade induced by train traffic along Qinghai-Tibet Railway,and provide the rational theoretical foundation for the rail transit assessment,the self-programming software of the train-track coupled dynamic system was employed to investigate the characteristics of the vertical applied force on sleeper induced by passenger trains.The researches show that,the simulation results of the self-compiling program are in accord with the field monitoring data,and the theory of the procedure is proper;the train-induced vertical acting force exerted on sleeper is in inverse proportion to the subgrade damping,and increases with the raising of the subgrade modulus and vehicle velocity,at the same time increases linearly with the rise of the rail gap;the dominant frequency bands are mainly within the action rate of shifting axle load,the vibratory energy reaches the maximum at the bogie action rate,and the sleeper vibration makes little different to the sleeper vertical applied force induced by passing trains;the effects of the freeze thawing status,rail gap width,and the train speed can not be ignored on the vertical acting force.Moreover,the function relationship of the acting force maximum value versus train velocity is given quantificationally.