地铁浮置板轨道系统导纳特性与钢轨波磨关系研究

Study on the Relationship Between Admittance Characteristics of Metro Floating Slab Track System and Rail Corrugation

为了探明钢弹簧浮置板轨道区段波磨发生机理及与轮轨系统参数影响规律。首先基于现场测试的钢轨波磨特征,分析波磨典型波长及其通过频率;其次建立轮对和钢弹簧浮置板轨道三维有限元模型,分析轮轨共振模态与浮置板轨道钢轨导纳特性,探讨钢轨扣件刚度、浮置板隔振器刚度与轮对振动模态对钢弹簧浮置板区段钢轨波磨的影响规律。结果表明(:1)钢轨扣件刚度对波磨发生和发展有重要的影响。钢轨扣件刚度越低,将激发钢轨较大的振动,在特定频段上过大的钢轨振动会导致对应波长的波磨加剧,进而加速波磨的发展。(2)从轮轨系统模态分析,358 Hz的钢轨横向弯曲变形频率与测试线路产生特征波长为31.7 mm波磨引起的轮轨振动频率较为接近;可通过采取减振措施来抑制轮轨系统在358 Hz处的横向振动响应,会相应地减缓钢轨磨耗。

Mechanism of rail corrugation and its influence on wheel-rail system parameters in steel spring floating slab track section is studied. Firstly, based on the observed characteristics of rail corrugation in field measurement, the typical wavelength and passing frequency of rail corrugation are analyzed. Secondly, three-dimensional finite element models of wheelset and steel spring floating slab track are established. The wheel-rail resonance modes and the rail admittance characteristics of the floating slab track are analyzed. And the effects of rail fastener stiffness, floating slab isolator ′ s stiffness and wheelset vibration mode on rail corrugation are discussed. The results show that:(1) Rail fastener stiffness has an important influence on the occurrence and development of rail corrugation. The lower the rail fastener stiffness is, the greater the rail vibration will be excited. Excessive rail vibration in a specific frequency range will aggravate the rail corrugation of the corresponding wavelength, and then accelerate the development of rail corrugation;(2) From the modal analysis of the wheel-rail system, the transverse bending deformation frequency of the rail at 358 Hz is close to the wheelrail vibration frequency caused by the rail corrugation with a characteristic wavelength of 31.7 mm produced by test measurement. Vibration reduction means can be taken to suppress the lateral vibration response of wheel-rail system at 358Hz and reduce rail wear accordingly.