摘要
研究目的:列车荷载的动力作用会引起路基弹性变形和累积沉降,严重时甚至会导致结构破坏。搭建基于直线源双轴电机的振动模拟装置,通过调整偏心质量、装置配重及输入频率,调控振动荷载输出,开展激振装置动力作用效应标定试验,分析相对于静平衡应力σ_(0)的峰值应力σ_(p)、谷值应力σ_(v)随电机偏心质量和转速变化规律,讨论激振装置稳定工作的上下限频率。研究结论:(1)随偏心片组数i和振动频率f增加,激振装置的输出动应力σ呈allometricl函数增长趋势,服从σ=A_(i)f^(B_(i))拟合关系,动平衡应力(σ_(p)+σ_(v))/2大于静平衡应力σ_(0),差值随f增加逐步扩大;(2)电机供电频率增加,双轴电机的偏心片反向旋转相位差逐渐减小,振动应力σ_(pv)=σ_(p)-σ_(v)相对于静平衡应力σ_(0)的误差率q与f呈正相关;(3)按路基设计振动应力σ_(pv)≈100 kPa进行标定试验,得拟合方程的估算值与测试值偏差率在-17.9%~8.7%范围;(4)本文研究可为激振试验中模拟铁路路基动力作用、明确铁路路基的动力特性提供可靠依据。
Research purposes:The dynamic effect of train load can cause elastic deformation and cumulative settlement of the subgrade,which can even lead to structural damage in serious cases.Build the vibration equipment based on a linear source biaxial motor.By adjusting the eccentric mass,device counterweight and input frequency,and regulating the vibration load output,this paper carries out calibration tests on the dynamic effect of the excitation equipment,analyzes the change rule of peak stressσ_(p)and valley stressσ_(v)relative to the static equilibrium stressσ_(0)with the eccentric mass and rotational speed of the motor,and discusses the upper and lower limit frequencies for the stable operation of the excitation equipment.Research conclusions:(1)With the increase of the number of eccentric piece group i and vibration frequency f,the output dynamic stressσof the excitation equipment is allometricl function growth trend,obeying the relationσ=A_(i)f^(B_(i)),and dynamic equilibrium stress(σ_(p)+σ_(v))/2 is greater than the static equilibrium stressσ_(0),the difference with the increase of f gradually expands.(2)The motor input frequency increases,the phase difference of the reverse rotation of the eccentric piece of the two-axis motor gradually decreases,and the error rate q and f of the vibration stressσ_(pv)=σ_(p)-σ_(v)relative to the static equilibrium stressσ_(0)are positively correlated.(3)Calibration test is carried out under the design dynamic loadσ_(pv)≈100 kPa of the subgrade,and the deviation rate between the estimated and tested values of the fitted equation is in the range of-17.9%~8.7%.(4)The research results can provide a reliable basis for simulating the dynamic action of railway subgrade and understanding the dynamic characteristics of railway subgrade in the excitation test.
作者
罗强
周建详
冯桂帅
张良
易梦笔
郑祉诚
LUO Qiang;ZHOU Jianxiang;FENG Guishuai;ZHANG Liang;YI Mengbi;ZHENG Zhicheng(Southwest Jiaotong University,Chengdu,Sichuan 610031,China)
出处
《铁道工程学报》
EI
北大核心
2022年第9期7-12,43,共7页
Journal of Railway Engineering Society
基金
国家自然科学基金项目(52078435)
四川省科技计划项目(21YYJC3358)
关键词
铁路路基
动力作用
激振装置
标定试验
误差分析
railway subgrade
dynamic action
excitation equipment
calibration test
error analysis
作者简介
罗强,1963年出生,男,教授。
