轨道车辆通过钢轨凹坑时的响应分析

Response Analysis of Train Passing Through Rail Squat

为研究钢轨凹坑对列车造成的动力学响应,采用实测的钢轨凹坑数据,建立轮轨滚动瞬态接触模型,通过Abaqus动力学显式算法求解车轮通过凹坑时的滚动状态。计算得到车轮通过凹坑后钢轨的Mises应力、轮轨接触力、轴箱处垂向加速度等数据。结果表明,钢轨凹坑会对列车产生短时较大冲击,此时轮轨接触位置Mises应力为681.7 MPa,改变轮轨接触状态,危害行车安全。且在车轮进入凹坑后的0.01 s内激发波长为42.67 mm的振动。从等效塑性应变计算结果可以看出钢轨凹坑会进一步扩大,且凹坑后扩大趋势大于凹坑前。

To study the dynamic effect of rail squat on wheel and track,a wheel-rail transient rolling contact model was established based on measured rail squat data,and the rolling state of the wheel passing through the rail squat was calculated by Abaqus/Explicit.The Mises stress,wheel rail contact force and vertical acceleration of axle box after the wheel passed through the squat were calculated.The results show that rail squat could cause an instantaneous huge impact on the wheel,and at this time the Mises stress at the wheel-rail contact position is 681.7 MPa,which could change wheel-rail contact relationship and endanger operation safety.Further,the vibration with a 42.67 mm wavelength is excited within 0.01 s after wheel set enters the squat.The calculation results of equivalent plastic strain show that the rail squat will further expand,and the expanding tendency where the wheel enters the squat is larger than where the wheel leaves the squat.