无砟轨道中减振垫组合减振性能对比分析

无砟轨道的整体刚度比有砟轨道大,为降低列车通过时的轮轨振动以及环境振动,有关无砟轨道的减振措施应运而生,考虑3种减振垫组合:轨下减振垫、轨下减振垫+枕下减振垫和轨下减振垫+板下减振垫。为研究3种减振垫组合情况下的减振性能,基于FEM方法,建立3种组合情况下的振动力学模型,对其进行谐响应分析,结果表明:轨下减振垫+枕下减振垫组合和轨下减振垫+板下减振垫组合不利于减少轮轨(钢轨)振动;轨下减振垫+板下减振垫组合有助于降低200 Hz频率以下环境(底座板)振动,最多能降低底座板振动加速度级为11.98 d B,频率越低减振能力越强;轨下减振垫+枕下减振垫组合仅能略微降低20 Hz频率以下环境(底座板)振动,最多能降低底座板振动加速度级为5.46 d B;相关计算和分析可为合理设计减振垫位置提供依据。

Comparative Analysis of Vibration Reduction Performance of Ballastless Track with Different Anti-vibration Pad Combinations

The integral stiffness of ballastless track is larger than that of ballast track. Vibration reduction measures are taken to reduce wheel-rail vibration and environmental vibration generated by the running train. Three different combinations of anti-vibration pad are considered in the paper:( 1) only rail pad;( 2) rail pad and sleeper pad;( 3) sleeper pad and slab pad. In order to research the harmonic response of vibration reduction performances of above three combinations, a vibration mechanical model is established with the method of FEM. The results show: combination( 2) and( 3) have no effect in reducing wheel-rail vibration; combination( 3) can reduce environmental( support layer) vibration under 200 Hz,and the vibration acceleration level of the support layer can be reduced up to 11. 98 d B; the effects are more obvious if frequency is low; combination( 2) can only reduce a little environmental( support layer) vibration under 20 Hz,and the vibration acceleration level of the support layer can be reduced by 5. 46 d B as the maximum. The calculations and analysis covered by this paper may provide some references for the design of proper pad location.