地铁钢轨波磨对轨道结构振动及减振特性影响

现场调查某地铁线路上普通短轨枕、先锋扣件和钢弹簧浮置板三种轨道的钢轨波磨特征,并分别进行振动测试,研究钢轨存在波磨时,三种轨道结构的振动特性及减振效果。结果表明:三种轨道结构都是内轨波磨明显,外轨表面不平顺幅值相比内轨都很小,可以忽略不计其影响;波磨主波长频率成分很容易在轨道各零部件(包括隧道壁)振动中激发出来,并且会引起较大幅值的振动;在4 Hz~200 Hz频率范围内,波磨激励下的减振型轨道依然具有良好的减振性能,但是与其最初设计用于的减振效果相比,有明显的下降;先锋扣件轨道短波长波磨会削减隧道壁在高频段的减振效果;钢弹簧浮置板轨道的波磨幅值显著,虽然对其隧道壁的减振效果影响不明显,但是会造成钢轨振动增加。

Influence of Metro Rail Corrugation on Track System’s Vibration and Mitigation Characteristics

Rail corrugation characteristics of 3 types of track structure of the selected metro line including fix-dual short sleepers, Vanguard fastener and steel spring floating slab were investigated. The vibration experiments were carried out to analyze the influence of rail corrugation on track system vibration and mitigation characteristic. The results show that the depths of corrugation on the inner rail is much more obvious than those on the outer rail. The main frequency mostly depends on the wavelengths of corrugation. In the range of 4~200 Hz, the vibration damping track with short-pitch corrugation still have a good vibration damping performance. The mitigating vibration effect at high frequency is reduced obviously due to the short-pitch corrugation on the rail of Vanguard fastener track. There’s no obvious influence of long-pitch corrugation of steel spring floating slab track on vibration mitigation. And the greater amplitude of corrugation on the steel spring floating slab track caused increase of rail vibration.