【作者】 曹洋；

【导师】 王平；

【作者基本信息】 西南交通大学 ， 道路与铁道工程， 2013， 博士

【摘要】 道岔设计中平面线型的选取是影响列车过岔速度和自身使用性能的关键因素之一,针对各种号码及不同应用范围的道岔,需选择合适的平面线型以满足行车安全性、平稳性和结构稳定性要求。本文在结合国内外现有理论的基础上,对道岔平面线型的选型评估及设计方法做了相关研究,主要内容分为以下几个方面：1.针对不同道岔平面线型轮轨接触几何关系计算方法的建立基于普通线路典型的轮轨接触几何关系计算方法,将其应用于道岔区接触关系求解过程中,其中利用三次样条函数拟合岔区钢轨控制断面,并在各断面间插值得到任意所需计算断面,然后采用迹线法将车轮上接触点的存在范围从踏面整个曲面缩小到一条空间曲线上,进而可通过最小距离法在所得钢轨计算断面和车轮迹线间精确搜索轮轨接触点位置,计算相关接触参数。以上述方法为基础,编制道岔区轮轨接触几何关系计算子程序,不仅可用于评价道岔平面线型类型对轮轨关系的影响,又可作为动力学计算中使上部车辆和下部道岔结构产生耦合关系的关键部分。2.车辆-道岔动力耦合模型的建立及求解以车辆动力学和道岔动力学理论为基础,建立车辆-道岔动力耦合模型,用于分析不同道岔平面线型对系统振动特性的影响,其中车辆子模型为由车体、两个转向架和四个轮对组成的单列整车多刚体模型,车体和两转向架分别考虑沉浮、横移、侧滚、摇头和点头五个自由度,各轮对考虑沉浮、横移、侧滚和摇头四个自由度,刚体间通过弹簧阻尼原件相联接；道岔子模型除包括转辙器、连接部分和辙叉三大主要结构以外,还考虑了各零部件对其振动的影响,然后利用有限单元法将其离散为有限元模型。使用道岔区轮轨接触关系将两子模型相耦合,采用哈密尔顿原理建立整体系统振动方程,并编制车辆-道岔动力耦合模型计算程序,从动力学角度指导道岔平面线型设计。3.各种平面线型下车辆-道岔动力耦合模型振动特性分析将道岔按号码大小进行分类,通过改变平面线型参数及类型分别为其设立工况,利用车辆-道岔动力耦合模型计算程序对比分析各工况振动特性,并研究列车过岔速度改变对系统动力响应的影响。由结果可知,小号码道岔选用单圆型和复圆型平面线型以及大号码道岔选用圆缓型和缓圆缓型线型时,均可保证在其各自允许过岔速度下列车侧向行驶的安全性、平稳性及道岔结构稳定性,且增加侧股曲线半径或为小号码道岔选用复圆曲线线型及大号码道岔选用缓圆缓曲线线型,将提高道岔的行车性能及对列车提速过岔的适应性,但应综合结构尺寸、设计及使用条件等因素确定具体线型。4.尖轨切削方式对转辙器部位系统动力响应及钢轨磨耗性能的影响研究利用车辆-道岔空间耦合振动模型及爱因斯磨耗指数计算方法,分别对不同号码道岔尖轨采用多种切削方式时的系统振动及钢轨磨耗进行对比分析,并研究列车过岔速度及线型参数改变对磨耗指数的影响。由结果可知,小号码道岔尖轨选用半切线型和半割线型切削方式时,车辆运行状态较优,钢轨磨耗性能良好,且随列车过岔速度和道岔侧股半径变化的改变量不大,此时相离半切线型切削方式对应各方面性能虽有所降低,但由于其显著提高了尖轨粗壮度,也可作为小号码道岔尖轨主要切削类型之一：大号码道岔尖轨切削方式中半切线型尖轨可在行车性能达到最优时所得钢轨磨耗指数较小,适用性最强。5.适用于多种道岔平面线型计算方法的建立建立了适用于多种道岔平面线型计算的平面参数法,推导了单圆型、复圆型、圆缓型和缓圆缓型四种道岔平面线型,以及切线型、半切线型、割线型、半割线型和相离半切线型五种尖轨切削方式关键参数的计算过程,并对其进行基本的结构尺寸及运动学评价,同时介绍了三种岔枕排布方式,即整体垂直于直股排布、辙叉区垂直于角平分线排布和整体扇形排布,此方法可减少由人为因素产生的误差,为道岔平面线型的精确设计打下了基础。6.道岔平面线型计算及绘图软件的开发与验证基于平面参数法开发了道岔平面线型计算及绘图软件,本软件由计算模块和绘图模块两部分组成,通过设定原始参数,可完成包括四种平面线型、五种尖轨切削方式和三种岔枕排布样式在内的多种设计的组合,配合绘图软件的使用,能够迅速绘制线型图用于方案比选,提高了工作效率。利用本软件针对低速小号码道岔和高速大号码道岔分别进行不同平面线型的试算,验证了软件的可用性。更多还原

【Abstract】 The horizontal alignment selection in turnout design is one of decisive factors to affect the speed by train passing over a turnout and the using performance. It is necessary to choose appropriate plane alignment for turnouts of various numbers and different application ranges to satisfy the train running safety and stability, and structural stationarity. Based on the existing theories in our country and abroad, the selection and evaluation and design method for turnout horizontal alignment were studied in this paper. The main content is divided into the following five aspects:1. wheel/rail contact geometry calculation method established according to various horizontal alignments for turnoutsBased on the typical wheel/rail contact geometry calculation method for common track rail, the turnout wheel/rail contact relationship calculation method was set up. The detail steps are listed:firstly apply cubic spline function to fit rail profiles in the key sections in turnout zone, and obtain profiles in any calculation section by interpolation between key sections; secondly use contact line method to get a space curve of all possible contact points on wheels; finally use minimum distance method to find out the wheel/rail contact point between the calculation section and the space curve, and then calculate all responding contact parameters. Following the steps above, the subprogram to calculate the wheel/rail contact geometry in turnout zone was developed. This subprogram can not only be applied into evaluating the influences of turnout horizontal alignment to wheel/rail contact relationship, but also was a key part to make the upper vehicle and lower switch structure form a coupling relationship which was essential in the dynamic program.2. Vehicle-turnout dynamic coupling model establishing and solutionBased on vehicle dynamics and turnout dynamics, vehicle-turnout dynamic coupling model was established to analyze the influences of horizontal alignment to the system vibration characteristics. The vehicle sub model was a single vehicle multi-rigid body model which was composed of the car body、two bogie and four wheelsets. In this model, the car body and the two bogie were both modeled with consideration of the five degrees of freedom including floating-sinking, sway, rolling, galloping and hunting; the wheelsets were modeled with consideration of four degrees of freedom including floating-sinking, sway, rolling and hunting; all rigid bodies were connected by the spring-damping component. Turnout sub model was built up with consideration of the three main structures including switch, common crossing and closure rail, and also of other components, and then all components were dispersed into finite element model. Apply the wheel/turnout contact relationship to couple the twp sub models, use Hamiltonian theory to establish the whole system equation, and then develop the calculation program for vehicle-turnout dynamic coupling model, and finally guide the turnout horizontal alignment design from the dynamic perspective. 3. Vibration characteristics analysis of vehicle-turnout dynamic coupling model with various horizontal alignmentsDifferent analysis cases were designed according to the parameters and the types of various horizontal alignments. The vibration characteristics of all cases were comparatively analyzed by using vehicle-turnout dynamic coupling model, and the influences of the speed by train passing over turnout to the system dynamic responses were also analyzed. Results show that small-size turnouts with single circular or composite circular alignment and large-size turnouts with circular-easement or easement-circular-easement curves can both satisfy the safety and stability when trains pass through turnout branch at their permissive speed, and the turnout structure stability; increasing curve radius of turnout branch or choosing small-size turnouts with composite circular alignment and large-size turnouts with easement-circular-easement curve can improve train running performance and turnout adaptability by train passing over it. However, the specific alignment should be determined with the overall consideration of structure dimensions、designs and working conditions.4. The influences of the cutting style of switch rail to the system dynamic responses and rail wearing ability in switch zoneBased on vehicle-turnout space coupling vibration model and wear index calculation method, the system vibration responses and rail wearing ability of various sizes turnouts with the switch rail of different cutting styles were comparatively analyzed, and the influence of the speed by train passing over turnout and alignment parameters’ changing to the wear index was also analyzed. Results show that when the cutting way of small-size turnout switch rail is semi-tangent or semi-secant alignment, the vehicle running state and rail wearing ability are good, and changes little with the change of the train passing speed and the radius of turnout branch. When the cutting way is disjoint semi-tangent, all respects of states are decreased, but this cutting style significantly improves the robustness of switch rail, so it can also be one of the cutting styles of switch rail; large-size turnout with semi-tangent switch rail can make the running state be best, and rail wear index less, so its applicability is best.5. The establishing of the calculation method applied to various turnout horizontal alignmentsThe plane parameter method was set up which could carry out the calculation of various turnout horizontal alignments; the key parameters of four horizontal alignments including single circular、composite circular circular-easement and easement-circular-easement, and of five switch rail cutting styles including tangent, semi-tangent, secant, semi-secant, and disjoint semi-tangent were derived, and all types of turnouts were evaluated in terms of structure dimension and kinematics. Three kinds of switch sleeper layout were introduced, which were the straight-line layout, the sector layout and a layout being vertical to the crossing angle in the crossing zone. All the switch sleeper layout methods can reduce error caused by human factors, and lay the foundation for turnout horizontal alignment design.6. The development and confirmation of the calculation and drawing software of turnout horizontal alignmentBased on the plane parameter method, the calculation and drawing software of turnout horizontal alignment was developed. This software consisted of the calculation module and the drawing module. By setting the original parameters, it could provide lots of design plans with different combinations of four horizontal alignments、five switch-rail cutting ways and three switch-sleeper layouts, and then it drew all alignments to provide for the plan comparison and selection. This software improved the efficiency of turnout alignment design. Different horizontal alignments for low-speed small-size turnout and high-speed large-size turnout were calculated respectively by using the software, and the results verify the usability of the software.更多还原