The Influence of Amplitude- and Frequency-Dependent Stiffness of Rail Pads on the Random Vibration of a Vehicle-Track Coupled System
The Influence of Amplitude- and Frequency-Dependent Stiffness of Rail Pads on the Random Vibration of a Vehicle-Track Coupled System
复制标题
轨枕幅值和频率相关刚度对车辆-轨道耦合系统随机振动的影响
DOI：
10.1155/2016/7674124
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发表时间：
2016
影响因子：
1.6
通讯作者：
Luo Zhe
中科院分区：
文献类型：
--
作者：
Wei Kai;Zhang Pan;Wang Ping;Xiao Junhua;Luo Zhe
测量了热塑性聚氨酯弹性体(TPE)轨垫外载荷与其压缩变形之间的非线性曲线。建立了钢轨-扣件系统的有限元模型，以确定TPE钢轨垫片在车辆静重量和钢轨扣件预紧力作用下的非线性压缩变形及其非线性静刚度。其次，采用车辆-轨道垂向耦合模型，研究了热塑性弹性体钢轨垫片的幅频变刚度对车辆-轨道随机振动的影响。结果表明，热塑性弹性体钢轨垫片的静刚度在19.1~37.9 kN/mm之间，与经典的割线刚度26.7 kN/mm有明显差异。此外，与轨垫的非线性幅频相关刚度相比，经典割线刚度不仅会严重低估轮轨耦合系统在65~150 Hz频率范围内的随机振动加速度水平，而且会改变车辆车轮和钢轨的主频分布。考虑到这些频率在65~150 HZ是低速铁路引起的地面振动加速度的主要频率，在预测低速铁路引起的环境振动时，应考虑钢轨垫层的非线性幅值和频变刚度。
The nonlinear curves between the external static loads of Thermoplastic Polyurethane Elastomer (TPE) rail pads and their compressive deformations were measured. A finite element model (FEM) for a rail-fastener system was produced to determine the nonlinear compressive deformations of TPE rail pads and their nonlinear static stiffness under the static vehicle weight and the preload of rail fastener. Next, the vertical vehicle-track coupled model was employed to investigate the influence of the amplitude- and frequency-dependent stiffness of TPE rail pads on the vehicle-track random vibration. It is found that the static stiffness of TPE rail pads ranges from 19.1 to 37.9 kN/mm, apparently different from the classical secant stiffness of 26.7 kN/mm. Additionally, compared with the nonlinear amplitude- and frequency-dependent stiffness of rail pads, the classical secant stiffness would not only severely underestimate the random vibration acceleration levels of wheel-track coupled system at frequencies of 65–150 Hz but also alter the dominant frequency-distribution of vehicle wheel and steel rail. Considering that these frequencies of 65–150 Hz are the dominant frequencies of ground vibration accelerations caused by low-speed railway, the nonlinear amplitude- and frequency-dependent stiffness of rail pads should be taken into account in prediction of environment vibrations due to low-speed railway.