嵌入式轨道弹性材料特性对钢轨振动与声辐射的影响

Influence of Elastic Material Characteristics on Vibration and Acoustic Radiation of Embedded Tracks

嵌入式轨道是一种普遍用于城市轨道交通减振降噪的轨道结构,该种轨道的钢轨埋置在高分子弹性材料中,只有轨头露出表面,所以高分子弹性材料是嵌入式轨道结构起到减振降噪作用的重要部分。利用轮轨滚动声辐射理论和有限元—边界元法,建立嵌入式轨道模型,调查高分子弹性材料弹性模量对嵌入式轨道结构振动声辐射的影响。在轮轨激励作用下,计算轨道结构的振动和声辐射响应,分析轨道结构辐射噪声的频谱规律。通过改变弹性材料的弹性模量,对比轨道结构振动沿纵向的衰减效果和沿横向的衰减效果,分析高分子弹性材料弹性模量对轨道结构减振特性的影响。

Embedded track, due to its best vibration-noise reduction effect, is widely used in urban rail transit. Its rails are embedded in the polymer elastic material with only rail heads appearing above the surface. Thus, property of the polymer elastic material plays an important role in the vibration-noise reduction of the embedded track structure. Based on the theory of wheel/rail rolling noise radiation, a FEM-BEM model was established for the embedded track. The influence of the elastic modulus of the polymer on the acoustic radiation of the track structure was investigated. Under the wheel/rail excitation, the vibration and acoustic radiation response of the track was calculated, and its radiation noise spectrum distribution was obtained. By changing the elastic modulus of the polymer, the longitudinal and transverse vibration attenuation effects of the track structure were analyzed and compared. The influence of the elastic modulus of the polymer on the vibration characteristics of the track structure was analyzed.