重载铁路钢轨焊接接头区域的轮轨动力作用特性

Characteristics of Wheel-rail Dynamic Interaction of Heavy Haul Railways due to the Rail Welding Joint

为研究重载货车通过钢轨焊接接头的轮轨作用特性,运用车辆-轨道耦合动力学理论,建立了30t轴重货车-轨道垂向耦合模型。对钢轨焊缝不平顺采用叠加谐波激扰模拟,仿真分析了30t轴重货车以120 km/h速度通过钢轨焊缝不平顺区时的轮轨动力学性能指标,以及短波不平顺的波长和波深对轮轨系统动力性能的影响。结果表明:在既有的钢轨焊缝作业标准条件下,30t轴重货车以120 km/h速度通过时,轮轨作用变化较小。当焊缝不平顺长波波长λ1为1 m,长波波深δ1为0.3 mm,短波波长λ2为0.1 m,短波波深δ2超过0.4 mm时,其轮轨力超过许用值250 kN;当短波波深超过0.7 mm时,30t轴重货车发生轮轨脱离现象。当焊缝不平顺短波波长变为0.2 m,短波波深超过0.6 mm时,轮轨力大于250 kN;当短波波深超过1.6mm时,30t轴重货车发生轮轨脱离现象。

In order to investigate the wheel-rail interaction performance of a heavy haul freight passing through the rail welding joint, a vertical coupled model between 30t-axle-load freight car track has been established on the basis of vehicle-track coupled dynamics theory. In this model, harmonic wave was adopted Car and the to simulate rail welding joint irregularity. The wheel-rail dynamic indices are analyzed at the speed of 120 km/h. The effects of wave length and depth on the wheel-rail dynam- ic performance are discussed specifically. Results show that according tO the existing railway standard of welded rail, the change of wheel-rail interaction force is not remarkable. The wheel-rail vertical force exceeds the limited value of 250 kN under the case that the length and depth of long wave are 1 m and O. 3 mm, and the length and depth of short wave are 0.1 m and 0.4 mm. The wheel will jump off the rail if the short wave depth is more than 0.7 mm. Furthermore, under the case that the lengthand depth of short wave is 0.2 m and 0.6 mm, the wheel-rail vertical force is bigger than 250 kN. If the depth of short wave is more than 1.6 mm, the phenomenon of wheel jumping off the rail will appears.