考虑非对称轨底坡的轮轨滚动接触应力分析
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摘要
研究目的:针对我国地铁线路钢轨因施工误差导致的非对称轨底坡处易出现疲劳伤损现象,利用我国地铁车辆常用的LM型面与CHN60钢轨,基于轮轨接触几何关系和Kalker三维非赫兹弹性体滚动接触理论及其数值程序CONTACT,分析非对称轨底坡对轮轨接触几何参数和轮轨接触力学特性的影响,揭示引起轮轨滚动接触疲劳的原因。研究结论:(1)随着轨底坡的减小,轮轨接触点对分布趋向于轨距角一侧,接触点对分布范围变窄,且轮轨接触斑面积减小,滑动区增大;(2)横移量小于4 mm时,右轨侧1/30、1/40、1/50三种轨底坡下的最大法向接触应力相差不大,但均明显高于轨底坡为1/20的值;在5～8 mm横移量范围内时,相同横移量下轮轨接触应力随着轨底坡的减小而增大;(3)同一横移量下轮轨体内最大等效应力值随着轨底坡的减小而增大,右轨侧轨底坡从1/20减小至1/50时最大等效应力均增加了60%左右,且等效应力沿纵向分布范围变窄,沿深度方向影响范围变小,等效应力作用趋于集中;(4)轨底坡的减小引起轮轨表层接触应力增大及轮轨体内等效应力增加,可能引起轮轨材料从表层到深度领域内的疲劳破坏,缩短轮轨的使用寿命;(5)本研究成果可为我国地铁线路检测、维修及轨底坡设置等提供参考。
Research purposes: With a view to the phenomenon of fatigue damage at the asymmetric rail cant caused by the construction error of subway rail in China,the wheel profile is of the type LM and the rail is the standard CHN60,both of them are commonly used in subway. Based on the wheel-rail contact geometry relationship and Kalker three-dimensional non-Hertzian rolling contact theory and its numerical program CONTACT,the influence of asymmetric rail cant on the wheel-rail contact geometric parameters and wheel-rail contact mechanical properties is analyzed and the cause of wheel/rail rolling contact fatigue is revealed.Research conclusions:( 1) With the decrease of rail cant,the distribution of the wheel-rail contact points tends to one side of the gauge angle,the distribution range of the contact points becomes narrower,the area of the wheel-rail contact spot decreases and the slip area increases.( 2) When the lateral displacement is less than 4 mm,the maximum normal contact stress at the rail cant of 1/30,1/40 and 1/50 on the right rail side has little difference,and is obviously higher than that at the rail cant of 1/20. In the range of 5 mm to 8 mm lateral displacement,the wheel-rail contact stress increases with the decrease of the rail cant.( 3) Under the same lateral displacement,the maximum equivalent stress in wheel-rail body increases with the decrease of rail cant. When the right rail cant decreases from 1/20 to 1/50,the maximum equivalent stress increases by about 60%,and the distribution range of the equivalent stress along the longitudinal direction becomes narrower,the influence range along the depth direction decreases,and the effect of the equivalent stress tends to be concentrated.( 4) The decrease of rail cant will increase the contact stress of wheel/rail surface and the equivalent stress in wheel/rail body,which may cause fatigue failure of wheel/rail material from surface to depth,and shorten its service life.( 5) The research results can provide references for the detection,maintenance and rail cant setting of subway line in China.
Research purposes: With a view to the phenomenon of fatigue damage at the asymmetric rail cant caused by the construction error of subway rail in China,the wheel profile is of the type LM and the rail is the standard CHN60,both of them are commonly used in subway. Based on the wheel-rail contact geometry relationship and Kalker three-dimensional non-Hertzian rolling contact theory and its numerical program CONTACT,the influence of asymmetric rail cant on the wheel-rail contact geometric parameters and wheel-rail contact mechanical properties is analyzed and the cause of wheel/rail rolling contact fatigue is revealed.Research conclusions:( 1) With the decrease of rail cant,the distribution of the wheel-rail contact points tends to one side of the gauge angle,the distribution range of the contact points becomes narrower,the area of the wheel-rail contact spot decreases and the slip area increases.( 2) When the lateral displacement is less than 4 mm,the maximum normal contact stress at the rail cant of 1/30,1/40 and 1/50 on the right rail side has little difference,and is obviously higher than that at the rail cant of 1/20. In the range of 5 mm to 8 mm lateral displacement,the wheel-rail contact stress increases with the decrease of the rail cant.( 3) Under the same lateral displacement,the maximum equivalent stress in wheel-rail body increases with the decrease of rail cant. When the right rail cant decreases from 1/20 to 1/50,the maximum equivalent stress increases by about 60%,and the distribution range of the equivalent stress along the longitudinal direction becomes narrower,the influence range along the depth direction decreases,and the effect of the equivalent stress tends to be concentrated.( 4) The decrease of rail cant will increase the contact stress of wheel/rail surface and the equivalent stress in wheel/rail body,which may cause fatigue failure of wheel/rail material from surface to depth,and shorten its service life.( 5) The research results can provide references for the detection,maintenance and rail cant setting of subway line in China.
引文
[1]温邦.地铁车轮踏面滚动接触疲劳形成机理及对策研究[D].成都:西南交通大学,2017.Wen Bang.Study on Mechanism and Countermeasure of Rolling Contact Fatigue on Metro Tread[D].Chengdu:Southwest Jiaotong University,2017.
[2]李霞,温泽峰,金学松.钢轨轨底坡对LM和LMA两种轮对接触行为的影响[J].机械工程学报,2008(3):64-69.Li Xia,Wen Zefeng,Jin Xuesong.Effect of Rail Cant on Rolling Contact Behavior of LM and LMA Wheelsets[J].Chinese Journal of Mechanical Engineering,2008(3):64-69.
[3]李霞,温泽峰,张剑,等.轨底坡对轮轨滚动接触行为的影响[J].机械强度,2009(3):475-480.Li Xia,Wen Zefeng,Zhang Jian,etc.Effect of Rail Cant on Wheel/Rail Rolling Contact Behavior[J].Journal of Mechanical Strength,2009(3):475-480.
[4]金学松.轮对/轨道滚动接触蠕滑率/力分析[J].铁道学报,1998(2):38-44.Jin Xuesong.Analysis of the Creepages and Creep Forces of Wheelset/rail Rolling Contact[J].Journal of the China Railway Society,1998(2):38-44.
[5]沈钢,张定贤.轨底坡对曲线钢轨侧磨影响的研究[J].铁道学报,1994(3):95-99.Shen Gang,Zhang Dingxian.Study on the Influence of Rail Bottom Slope on the Side Wear of Curved Rail[J].Journal of the China Railway Society,1994(3):95-99.
[6]钱瑶,王平,苏谦,等.轨底坡对高速铁路轮轨接触行为影响分析[J].铁道工程学报,2018(3):18-25.Qian Yao,Wang Ping,Su Qian,etc.Effect Analysis of Rail Cant on the Wheel-rail Contact Behavior of Highspeed Railway[J].Journal of Railway Engineering Society,2018(3):18-25.
[7]王开文.车轮接触点迹线及轮轨接触几何参数的计算[J].西南交通大学学报,1984(1):92-102.Wang Kaiwen.Calculations of Track of Wheel Contact Point and Geometric Parameters of Wheel-rail Contact[J].Journal of Southwest Jiaotong University,1984(1):92-102.
[8]温泽峰,金学松.两种型面轮轨滚动接触蠕滑率/力的比较[J].工程力学,2002(3):82-89.Wen Zefeng,Jin Xuesong.Comparison of Creep Rate/force of Rolling Contact between Wheel and Rail with Two Profiles[J].Engineering Mechanics,2002(3):82-89.
[9]Kalker J.J.Three-dimensional Elastic Bodies in Rolling Contact[M].Netherlands:Kluwer Academic Publishers,1990.
[10]Bower A.F.,Johnson K.L.Plastic Flow and Shakedown of the Rail Surface in Repeated Wheel-rail Contact[J].Wear,1991(1):1-18.
[2]李霞,温泽峰,金学松.钢轨轨底坡对LM和LMA两种轮对接触行为的影响[J].机械工程学报,2008(3):64-69.Li Xia,Wen Zefeng,Jin Xuesong.Effect of Rail Cant on Rolling Contact Behavior of LM and LMA Wheelsets[J].Chinese Journal of Mechanical Engineering,2008(3):64-69.
[3]李霞,温泽峰,张剑,等.轨底坡对轮轨滚动接触行为的影响[J].机械强度,2009(3):475-480.Li Xia,Wen Zefeng,Zhang Jian,etc.Effect of Rail Cant on Wheel/Rail Rolling Contact Behavior[J].Journal of Mechanical Strength,2009(3):475-480.
[4]金学松.轮对/轨道滚动接触蠕滑率/力分析[J].铁道学报,1998(2):38-44.Jin Xuesong.Analysis of the Creepages and Creep Forces of Wheelset/rail Rolling Contact[J].Journal of the China Railway Society,1998(2):38-44.
[5]沈钢,张定贤.轨底坡对曲线钢轨侧磨影响的研究[J].铁道学报,1994(3):95-99.Shen Gang,Zhang Dingxian.Study on the Influence of Rail Bottom Slope on the Side Wear of Curved Rail[J].Journal of the China Railway Society,1994(3):95-99.
[6]钱瑶,王平,苏谦,等.轨底坡对高速铁路轮轨接触行为影响分析[J].铁道工程学报,2018(3):18-25.Qian Yao,Wang Ping,Su Qian,etc.Effect Analysis of Rail Cant on the Wheel-rail Contact Behavior of Highspeed Railway[J].Journal of Railway Engineering Society,2018(3):18-25.
[7]王开文.车轮接触点迹线及轮轨接触几何参数的计算[J].西南交通大学学报,1984(1):92-102.Wang Kaiwen.Calculations of Track of Wheel Contact Point and Geometric Parameters of Wheel-rail Contact[J].Journal of Southwest Jiaotong University,1984(1):92-102.
[8]温泽峰,金学松.两种型面轮轨滚动接触蠕滑率/力的比较[J].工程力学,2002(3):82-89.Wen Zefeng,Jin Xuesong.Comparison of Creep Rate/force of Rolling Contact between Wheel and Rail with Two Profiles[J].Engineering Mechanics,2002(3):82-89.
[9]Kalker J.J.Three-dimensional Elastic Bodies in Rolling Contact[M].Netherlands:Kluwer Academic Publishers,1990.
[10]Bower A.F.,Johnson K.L.Plastic Flow and Shakedown of the Rail Surface in Repeated Wheel-rail Contact[J].Wear,1991(1):1-18.