轨道参数对无砟轨道振动特性的影响分析

依据弹性支撑块式无砟轨道的力学特征,以及地铁车辆的实际参数,建立了轮轨非线性耦合系统模型.通过对该模型的求解可以得到系统中钢轨和轨枕的竖向振动加速随时间的变化过程,结合快速傅里叶变化的方法,分析了钢轨和轨枕振动加速度在频域中的变化.引入根据人体敏感度进行修正后得到的振动能量指标,对钢轨以及轨枕的振动能量进行量化分析,评价了系统中各个参数对于系统振动特性的影响.结果显示,增加各垫层的刚度和阻尼都能直接导致系统振动能量的减少,其中增加刚度导致振动能量减少的幅度要大.

Influence of the Track Parameters on Vibration Characteristics of Ballastless Track

A nonlinear coupling model of wheel and rail was established according to the mechanical characteristic of ballastless track with elastic supporting block and the actual parameters of metro vehicle. The time-variant vertical acceleration of the rail and the sleepers can be calculated from the model, and the frequency-dependent acceleration was verified by the fast Fourier transform algorithm. A vibration power fixed by human sensitivity was introduced to quantify the vibration energy of the rail and sleepers. The impact of the parameters in the model was evaluated. The result shows the vibration energy is reduced with the increase of the stiffness and damp, meanwhile, the decrease in amplitude of the vibration energy that is resultant from the increase of the system stiffness is more prominent.