采用新型钢轨焊缝保护装置后钢轨焊缝处的轮轨动力学特性

根据轮轨相互作用机理,建立安装新型钢轨焊缝保护装置后钢轨焊缝处的车辆—轨道耦合动力学模型,对此处的轮轨垂向力、脱轨系数、轮重减载率等轮轨动力学指标进行仿真计算,并分别与采用鼓包鱼尾板和没有焊缝保护装置时进行对比,研究采用新型钢轨焊缝保护装置时焊缝处的轮轨动力学特性。对比分析结果表明:采用新型钢轨焊缝保护装置后,轮轨垂向力降幅分别为1.28%和4.63%,脱轨系数降幅分别为1.49%和2.94%,轮重减载率降幅分别为3.41%和7.68%;新型钢轨焊缝保护装置在各速度条件下均能够有效地减小焊缝振动和动态受力。由此可见,采用新型钢轨焊缝保护装置,可消除打螺栓孔带来的安全隐患,有效减小焊缝处的动力响应,加强焊缝处的轨道结构整体性。现场动态测试结果进一步验证了新型钢轨焊缝保护装置结构的合理性。

Wheel-Rail Dynamic Characteristics at Rail Welded Joint after Installing New Protection Device for Rail Welded Joint

According to wheel-rail interaction mechanism,vehicle-track coupling dynamic model at rail welded joint was built after installing new protection device for rail welded joint.Simulation calculation was carried through on such wheel-rail dynamic indexes as wheel-rail vertical force,derailment coefficient,wheel unloading rate and so on.The wheel-rail dynamic characteristics at rail welded joint using new protection device for rail welded joint were analyzed and compared respectively with those of using bulge fish plate and those of without using any protection device for welded joint.The analysis and comparison results show that after using new protection device for rail welded joint,the decreasing range of wheel-rail vertical force is 1.28% and 4.63% respectively,that of derailment coefficient is 1.49% and 2.94% respectively,and that of wheel unloading rate is 3.41% and 7.68% respectively.The new protection device can effectively reduce vibration and the dynamic force of rail welded joint under all speed conditions.Thus it can be seen that the new protection device for rail welded joint can eliminate the hidden danger of bolt hole,effectively reduce dynamic response and strengthen track structure integrity at rail welded joint.The results of field dynamic test have further verified the rationality of the structure of new protection device for rail welded joint.