道床板长度对减振垫轨道结构振动性能影响分析

橡胶减振垫整体道床是一种新型的减振轨道结构,然而,工程应用中,单元道床板结构长度的选择尚无明确指导性意见。采用模态分析、谐响应分析法分析不同道床板长度橡胶减振垫整体道床结构固有频率、振型及传递函数。分析表明:(1)单元道床板长度变化对道床垂弯、道床扭转振型主振频率影响较明显;(2)2.5、3.75 m单元道床轨道结构频谱幅值出现在一阶横弯振型频率,而≥5 m的道床板,其频谱幅值主要出现在道床沉浮振型对应频率附近;(3)减振垫整体道床频谱曲线幅值随着道床单元结构长度的增加而大幅减小;(4)当单元道床结构长度≥5 m时,频响幅值随单元长度变化不大。

Analysis of Track Slab Length Impact on Vibration Performance of Damping Track Structure

The railway track with rubber vibration-damping pad is a new type of vibration damping track.However,the selection of the track slab length is not specified in engineering practices. Two methods of modal analysis and harmonic response analysis are applied to analyze the natural frequency,vibration mode and transfer functions of track slabs of different lengths. Research results show that:( 1) the length of the unit slab has significant influences on the vibration frequency of vertical bending and torsion;( 2)spectrum amplitude of unit slab appears in the transverse bending frequency of the first order at the lengths of 2. 5,3. 75 m and when it is greater than or equal to 5m,it appears near the corresponding frequency of the floating vibration mode;( 3) the spectrum amplitude of curves is greatly reduced with increase in length of the unit track slab;( 4) the spectrum amplitude varies a little with the change of unit length where the length of the unit track structure is 5m or over.