高速铁路SKL15扣件弹条断裂原因分析

Analysis on fracture causes of SKL15 fastener clips in high-speed railway

摘要:

为了分析高速铁路运营线路扣件弹条断裂原因,以SKL15型弹条为研究对象,采用现场测试与仿真分析相结合的方法进行研究。首先,现场调查线路的波磨情况与弹条的振动响应特性；其次,建立扣件系统有限元模型,分析弹条在自由状态和安装状态下的模态特征,并进行基于模态叠加法的谐响应分析,通过对比现场测试结果和仿真结果,证明模型的可靠性；最后,结合测试结果和线路运营情况,分析造成弹条断裂的原因并提出整治措施。结果表明:造成弹条断裂的主要原因是列车以120 km/h的时速通过显著波长为50~60 mm的波磨区段时所激发的载荷频率与安装状态下的弹条模态频率（550~650 Hz）十分接近,从而引起弹条强烈的共振作用,导致弹条跟端应力显著增大,最终引发疲劳损伤。针对这一原因,提出了如钢轨打磨、列车调速、弹条结构优化等一系列解决方法。

Abstract:

To analyze the reasons for the fracture of fastener clips in high-speed railway operating lines, SKL15 clips were studied as the object using a method of combining field test and simulation analysis. First, an on-site investigation of rail corrugation and vibration response characteristics of clips was performed. Then, a finite element model of the fastening system was established. The modal characteristics of the clips in their free and assembly states were analyzed, and a harmonic response analysis was carried out based on the modal superposition method. The reliability of the model was proved by comparing the field test results with the simulation results. Finally, in combination with the test results and the railway operation situation, the fracture causes of the fastener clips were analyzed, and remedial measures were put forward. Results showed that the main reason for the fracture of clips was that the load frequency excited when the train passed through the corrugation section with a significant wavelength of 50-60 mm at a speed of 120 km/h was very close to the modal frequency (550–650 Hz) of the clips in the assembly state, which caused the clips to have a strong resonance effect and resulted in the significant increase in the stress at the heel end of the clips, and eventually, fatigue damage. As a result, some solutions were put forward, such as rail grinding, train speed adjustment, and clip structural optimization.