基于NURBS的固定辙叉心轨廓形参数化设计方法  

Parametric design method of nose rail profile in fixed-nose crossing based on NURBS

作　　者：赵卫华 黄子惠[1] ZHAO Weihua;HUANG Zihui(School of Civil Engineering,Fujian University of Technology,Fuzhou 350118,China;Key Laboratory of Underground Engineering of Fujian Province,Fujian University of Technology,Fuzhou 350118,China)

机构地区：[1]福建工程学院土木工程学院,福建福州350118 [2]福建工程学院地下工程福建省高校重点实验室,福建福州350118

出　　处：《铁道科学与工程学报》2023年第3期909-919,共11页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51508098);福建省自然科学基金资助项目(2020J01888)。

摘　　要：为实现固定辙叉心轨廓形参数化设计,基于非均匀有理B样条(NURBS)理论,提出一种考虑固定辙叉心轨廓形几何特征的参数化设计方法。以60 kg/m钢轨12号固定辙叉为例,选取心轨关键控制参数轨顶横坡和复合圆弧段比例系数对心轨廓形进行方案设计,分析轨顶横坡和复合圆弧段比例系数对心轨廓形变化的影响权重;分析各方案下结构不平顺、轮轨接触点分布、轮对侧滚角以及滚动圆半径差等接触几何关系指标变化规律。研究结果表明:复合圆弧段比例系数对心轨粗壮度影响较大;随着心轨顶宽增加,轨顶横坡对心轨廓形影响权重逐渐增加;轨顶横坡越大,心轨轮载过渡范围逐渐后移,对心轨承力有利;当轨顶横坡为1/10,复合圆弧段比例系数为1/3(方案4)时,竖横向不平顺相对于各方案最小值增大2.06%和1.61%,但轮载过渡位置在距心轨理论尖端330~335 mm范围内,心轨承载断面宽度最大;复合圆弧段比例系数对滚动圆半径差和轮对侧滚角变化影响权重较轨顶横坡大,在横移量-8~+4 mm范围内,随着心轨顶宽增加,方案4中滚动圆半径差和轮对侧滚角最小。综合考虑各方案轮轨接触几何参数变化规律可知,方案4廓形参数选取较为合理。该方法可使心轨廓形设计更具有针对性和可预测性。A parametric optimization method was presented based on the Non-Uniform Rational B Spline(NURBS) theory to realize the optimization of the nose rail profile in a fixed-nose crossing.The geometric characteristics of the nose rail profile were considered in this method.Taking 60 kg/m rail No.12 turnout with a fixed-nose crossing as an example,parametric design cases for two key parameters involving railhead slope and proportion coefficient of composite circular arc were proposed to analyze the influencing weights of the parameters on the variation of nose profiles and analyze the indexes of the wheel/rail contact geometry including wheel/rail contact points distribution,structure irregularity,wheelset rolling angle and rolling radius difference.The results show the proportion coefficient of composite circular arc can significantly affect the robustness of the nose rail.The influencing weight of railhead slope on nose profile gradually increases with the increase of the railhead width.The larger the railhead slope is,the farther the transition zone is from the crossing theoretical point,which is benefit to the bearing capacity of the nose rail.By comparing the minimum magnitudes of all design cases,the vertical and lateral irregularity in design case 4 in which the railhead slope is 1/10 and the proportion coefficient is 1/3 increases only by 2.06% and 1.61%,respectively.The wheel/rail transition zone is within 330 mm to 335 mm from the crossing theoretical point.Therefore,the width of the nose rail section which begins to bear the wheel load is maximum among all cases.The proportion coefficient of composite circular arc has a greater influencing weight on rolling radius difference and wheelset rolling angle than the railhead slope.In the range from-8 mm to 4 mm of the wheelset lateral displacement,the rolling radius difference and wheelset rolling angle in design case 4 are minimum with the increase of the nose rail width.Considering the wheel-rail contact geometry analysis of all design cases,the profile parameter

关 键 词：固定辙叉 心轨廓形 非均匀有理B样条 参数化设计 轮轨接触几何关系 

分 类 号：U213.62[交通运输工程—道路与铁道工程]