针对城市高架轨道进行减振降噪研究设计,需要了解轨面短波不平顺作用下轨道-桥梁系统的动力性能和振动响应的影响规律.用UM和ANSYS软件建立地铁B型车和32 m高架简支箱梁模型,结合实测结果进行模型验证,使用实测上海地铁1号线轨面不平顺数据,预处理后输入车辆-轨道模型中计算时域轮轨垂向力.通过APDL语言编写do循环将轮轨力施加到箱梁桥钢轨上模拟车辆行进,计算60、70、80 km/h 3个速度下高架轨道各个部位振动响应,以轮轨力和箱梁1/2跨中钢轨,桥面板垂向振动加速度从时域、频域角度分析轨面短波不平顺对轨道-桥梁系统振动影响规律.结果表明,轨面短波不平顺作用下会产生波幅比较大的垂向轮轨力,随着行驶速度上升逐渐增大;钢轨加速度随着速度增大,增加幅度逐渐上升;3个速度对应钢轨振动最不利波长分别为2.083 3、3.086 4、3.527 3 cm,桥梁振动最不利波长分别为26.455 0、30.864 2、35.273 4 cm.
Analysis on the Influence of Short-wave Irregularities on the Vibration of Elevated Rail Structure
To study and design vibration reduction and noise reduction for urban elevated rail,it is necessary to understand the dynamic performance and vibration response of rail-bridge system under the action of short-wave irregularities.UM and ANSYS software were used to establish the model of metro B and 32 m elevated simple supported box beam,and the measured results were combined for model validation.The measured data of Shanghai Metro Line 1 were used,and the time field wheel-rail vertical force was input into the vehicle-track model to calculate the time-domain wheel rail vertical force.APDL language were used to write do cycle,the wheel rail force was applied to the box girder bridge rail to simulate vehicle travel,and the vibration response of various parts of the elevated rail was calculated at the speed of 60,70,80 km/h.In rail force and 1/2 span rail of the box beam,the deck plate vertical vibration acceleration was used to analyzed the impact of the rail surface short wave irregularities on the rail-bridge system vibration from the perspective of time domain and frequency domain.The results show that under the action of short-wave irregularities,a vertical wheel rail force with a relatively large amplitude is generated.The rail acceleration increases gradually with the increase of the speed.The most unfavorable wavelengths corresponding to the rail vibration are 2.083 3,3.086 4,and 3.527 3 cm,respectively,and the most unfavorable wavelengths for bridge vibration are 26.455 0,30.864 2,and 35.273 4 cm,respectively.
万方数据
维普
