【作者】 曾志平；

【导师】 陈秀方；

【作者基本信息】 中南大学 ， 道路与铁道工程， 2006， 博士

【摘要】 无缝道岔和桥上无缝线路是高速、重载铁路强化轨道结构的关键技术。其力学机理比较复杂，历来是铁路现代化技术研究中的热点和难点。新建铁路和城市高架线路，由于受到地形或环保等条件的制约，不可避免的要将无缝道岔铺设在桥上。桥上无缝道岔的出现产生了两个新的研究领域，即桥上无缝道岔纵向附加力与位移研究以及列车—道岔—桥梁系统动力学研究。由于桥上无缝道岔结构的复杂性，其力学机理比之路基无缝道岔和桥上无缝线路更为复杂，将成为我国大力发展跨区间无缝线路过程中的又一关键技术。目前，我国还没有在桥上铺设无缝道岔的工程经验，相关的理论储备也非常少。为了用科学韵理论指导未来的工程实践，本文进行了如下一些开创性的理论研究：(1)针对有碴轨道结构，将道岔、桥梁和墩台视为一个系统，建立了计算桥上无缝道岔(渡线)伸缩力与位移的有限元力学模型。梁体和钢轨划分杆单元；岔枕划分为弹性点支承梁单元；固定支座处桥梁墩台视为线性弹簧单元；道床纵向阻力、扣件纵向阻力、扣件阻矩、限位器阻力、间隔铁阻力用非线性弹簧模拟。根据能量变分原理和形成矩阵的“对号入座”法则建立了模型求解的非线性方程组。基于科学计算语言MATLAB编制了相应的计算程序，并实现了计算机运算。(2)运用所建立的桥上无缝道岔(渡线)伸缩力与位移计算模型，分析了简支梁桥上无缝道岔、连续梁桥上无缝道岔、连续刚构桥上无缝道岔以及连续梁桥上无缝渡线的伸缩力与位移的分布规律；将桥上无缝道岔、路基无缝道岔、桥上无缝线路伸缩力与位移的分布规律进行了对比，研究了其变化规律；研究了影响桥上无缝道岔伸缩力与位移的参数，如轨温变化幅度、梁温差、扣件阻力、道床阻力、限位器间隙、岔枕抗弯刚度、限位器位置、梁跨长度、桥墩刚度等，并对参数的合理取值提出了建议。(3)针对有碴轨道结构，运用有限单元法，建立了多层支承体系的线路结构空间振动模型。对于路基区间线路，采用钢轨—轨枕—道床弹簧-阻尼振动模型；对于路基岔区线路，采用钢轨—岔枕弹簧-阻尼振动模型；对于桥上区间线路和桥上岔区线路，采用钢轨—轨枕／岔枕—桥梁弹簧-阻尼振动模型。运用弹性系统动力学总势能不变值原理及形成矩阵的“对号入座”法则建立了车辆空间振动方程组、路基区间线路结构空间振动方程组、桥上区间线路结构空间振动方程组、路基岔区线路结构空间振动方程组、桥上岔区线路结构空间振动方程组。基于科学计算语言MATLAB编制了列车—轨道系统、列车—轨道—桥梁系统、列车—道岔系统以及列车—道岔—桥梁系统空间振动分析程序。利用已有的试验结果和研究成果对模型的有效性进行了验证。(4)利用所建立的列车—道岔—桥梁系统空间振动模型，以温福客运专线田螺大桥为例，拟定桥上铺设了由两组38号道岔组成的单渡线，计算了“中华之星”电动车组，按一动四拖的编组方式，分别以200km／h和120km／h的速度直逆向和侧向通过时，列车—道岔—桥梁系统空间振动的动力响应，并与列车通过路基无缝道岔和桥上无缝线路的动力响应进行了对比，研究了系统响应的变化规律。(5)以温福客运专线田螺大桥为例，分析了影响列车—道岔—桥梁系统空间振动的因素，如列车运行速度、轨下竖向刚度、枕下竖向均布刚度、轨下横向刚度、枕下横向均布刚度、道岔区竖向不平顺幅值、桥梁高度、桥梁宽度、桥墩高度等，并对参数的合理取值提出了建议。本文的研究成果对桥上无缝道岔的设计、施工和养护具有重要的指导意义。更多还原

【Abstract】 Both seamless turnout and continuously welded rail (CWR) track onbridge are key techniques for high speed railway and heavy haul railwayto strengthen track structure. The mechanical mechanisms of bothseamless turnout and CWR track on bridge are very complex and theyhave always been the focal points and diffficulty points of railwaymodernization technique research. Because of the restriction of landformor environmental protection, seamless turnout will be unavoidably laid onbridge in newly-built railway or city elevated railway. The appearance ofseamless turnout on bridge leads to the appearances of two new researchdomains, which include research of additional longitudinal force anddisplacement of seamless turnout on bridge and research oftrain-turnout-bridge system dynamics. Because of the complexity ofseamless turnout on bridge, its mechanical mechanism is more complexthan that of seamless turnout on roadbed and of CWR track on bridge.Therefore seamless turnout on bridge will become another key techniquein the process of CWR track across station developing fast in China. Atthe present time, there is no engineering experience of seamless turnouton bridge in China, and the related theory research is also very few. Inorder to guide the future engineering practice with scientific theory, thispaper finished some pioneer theory researches as follows:(1) Aiming at ballast track, a finite element mechanics model wasestablished which can calculate the tensile and compressive force anddisplacement of seamless turnout (crossover) on bridge. In the model, theseamless turnout, beam, pier and abutment were considered as a system.The beam of bridge and rail was divided by bar element; turnout tie wasdivided by beam element; pier or abutment in fixed bearing wasconsidered as linear spring element; longitudinal ballast resistance,longitudinal fastener resistance, fastener torque, spacer pieces resistanceand spacing iron blocks were considered as nonlinear spring element. The nonlinear equation sets to solve the model were established by energyvariation principle and the "set-in-right-position" rule for formulatingmatrixes. Corresponding computer calculating programs weredeveloped with MATLAB.(2) The calculation model of tensile and compressive force anddisplacement of seamless turnout (crossover) on bridge was applied. Thedistribution rules of the tensile and compressive force and displacementof seamless turnout on simple-supported beam bridge, seamless turnouton continuous beam bridge, seamless turnout on continuous frame bridge,and crossover on continuous beam bridge were analyzed. The distributionrules of the tensile and compressive force and displacement of seamlessturnout on bridge, seamless turnout on roadbed and CWR track on bridgewere compared and the variation laws were studied. Some parametersinfluencing the tensile and compressive force and displacement ofseamless turnout on bridge were studied, such as the algebraic differencebetween rail temperature and the stress-free temperature, the maximumtemperature difference of beam, fastener resistance, ballast resistance, thegap of spacer, the rigidity of turnout tie, the location of spacer, the lengthof beam, the stiffness of pier and so on. The reasonable values ofparameters were suggested.(3) Aiming at ballast track, a track structure spatial vibration modelof multi-layer supporting system was established by using finite elementmethod. The rail-sleeper-roadbed spring-damping vibration model wasbuilt for section track on roadbed; the rail-turnout tie spring-dampingvibration model was built for turnout track on roadbed; therail-sleeper/turnout tie-bridge spring-damping vibration model was builtfor section track on bridge or turnout track on bridge. The vehicle spatialvibration equation sets, section track on roadbed spatial vibrationequation sets, section track on bridge spatial vibration equation sets,turnout track on roadbed spatial vibration equation sets and turnout trackon bridge spatial vibration equation sets were formulated by using the principle of total potential energy with stationary value in elastic systemdynamics and the "set-in-right-position" rule for formulating matrixes.The spatial vibration analysis programs of train-track system,train-track-bridge system, train-turnout system and train-turnout-bridgesystem were developed respectively with MATLAB. The availability ofmodels was testified by existing test results and research findings.(4) The train-turnout-bridge system spatial vibration model wasapplied. Taking TIAN-LUO major bridge in WENZHOU-FUZHOUrailway line for passenger as an example, it was assured that there was acrossover combined with two No.38 turnouts on the bridge. Thetrain-turnout-bridge system spatial vibration dynamic responses wereanalyzed when "China Star" high speed train with 1 locomotive and 4passenger cars at the speed of 200km/h through turnout main and at thespeed of 120km/h through turnout branch. The results were comparedwith those of train through turnout on roadbed and of train though CWRtrack on bridge. The variation laws of responses were studied.(5) Taking TIAN-LUO major bridge in WENZHOU-FUZHOUrailway line for passenger as an example, some parameters influencingtrain-turnout-bridge system spatial vibration were studied, such as trainrunning speed, rail supporting vertical stiffness, sleeper supportingvertical uniform stiffness, rail supporting lateral stiffness, sleepersupporting lateral uniform stiffness, the maximum value of verticalirregularity in turnout, the height of beam, the width of beam, the heightof pier and so on. The reasonable values of parameters were suggested.The research findings of this paper are important to guide the design,construction and maintaining of seamless turnout on bridge.更多还原