高架轨道轮轨噪声预测分析

随着我国城市轨道交通的快速发展,高架轨道作为一种经济、实用、安全、快速的交通模式,在城市轨道交通建设中得到越来越广泛的运用,但由此带来的振动噪声对周围环境的影响也变得十分突出。通过建立轮轨噪声预测模型,运用有限元法分析箱型梁、U型梁阻抗,对高架轨道轮轨噪声进行预测分析。讨论了桥梁截面型式、行车速度、轨道扣件刚度、桥梁结构阻尼、桥梁支座刚度对高架轨道轮轨噪声的影响。分析结果表明,行车速度和扣件刚度对轮轨噪声有较大影响,在200 Hz以下,轮轨噪声总体上随着扣件刚度的增大而增大;在200~800 Hz范围内,轮轨噪声随着扣件刚度的增大反而减小;在800 Hz以上,扣件刚度对轮轨噪声无明显影响。桥梁截面型式仅在低频部分对轮轨噪声有较大影响,而桥梁结构阻尼、桥梁支座刚度则对高架轨道轮轨噪声影响甚微。

Analysis of Elevated Rail Wheel/Rail Noise Prediction

With the rapid development of urban rail transit in China,elevated rail as an economic,practical,safe and rapid transport mode,has been used widely in urban trans-port.But at the same time,the influence of vibration and noise caused by elevated rail over the environment becomes very prominent.In this paper,the finite element method is used to establish the prediction model of wheel/rail noise, and to analyze the impedance of box beam and U beam and predicte the wheel/rail noise. The influence of bridge cross-section type,vehicle speed,track fastener stiffness, bridge structural damping,and bridge bearing stiffness over the wheel-rail noise on elevated rail is discussed.The analy-sis results show that,the driving speed and fastener stiff-ness have greater influence over the wheel /rail noise, which is below 200 Hz,and the increase of fastener stiff-stiffness will directly raise the wheel/rail noise. But in the range of 200 ~ 800 Hz,the increase of fastener stiffness will reduce the wheel-rail noise;while above 800 Hz,fastener stiffness will have no obvious effect on wheel/rail noise.The cross-section type bridge has a greater influence over the wheel/rail noise in part of the frequency,but the structural damping and support stiffness of a bridge only have less effect over the wheel/rail noise.