【作者】 李笑男；

【导师】 高亮； 张丁盛；

【作者基本信息】 北京交通大学 ， 道路与铁道工程， 2008， 硕士

【摘要】 城市轨道交通作为城市公共交通的骨干,以其大容量、准时快捷、安全高效的优势,对改善大城市人们出行问题、缓解大城市的交通拥堵状况,发挥了其它交通工具难以替代的作用,因此世界各国竞相发展。由于城市轨道交通相比国有铁路有其自身的特点,所以有必要结合城市轨道交通的特点深入研究符合我国城市轨道交通特点的轨道结构形式,为我国城市轨道交通事业的发展提供便利和保障。道岔结构作为重要的轨道结构之一,是跨区间无缝线路的技术难点。我国地铁线路的道岔结构类型,一般有单开道岔、单渡线和交叉渡线等,道岔号数以12号、9号和7号道岔最为常用,其尖轨的平面线形分为直线尖轨和曲线尖轨。虽然直线型尖轨跟端存在活接头,稳定性较差,容易形成病害,但对于行车速度较低的城市轨道交通,其尖轨耐磨,使用寿命长,扳动力小,只须一点牵引,而且结构简单,左右开道岔可以互换使用,减少了现场备品的数量,因此在城市轨道交通中大量采用。而交叉渡线是车站咽喉区附近一种常见的道岔设备,可以在很小的范围内实现线路的两两对接,在很大程度上缩小了占地面积,在我国已建和在建的地铁线路中较多地使用,分析研究其受力和变形规律,及其设计理论和设计方法,可用于指导城市轨道交通道岔的设计、铺设及养护维修。但国内外很少对其进行过理论研究,综合考虑各种因素,本文选择9号直线尖轨交叉渡线模型进行研究分析。本文针对城市轨道交通高架桥及地面线上铺设无砟轨道交叉渡线的特点,运用北京交通大学现有的有限元方法,建立了桥上无砟轨道9号直线尖轨交叉渡线道岔的纵横向耦合有限元模型,分析了交叉渡线的受力和变形,并于路基上无砟轨道交叉渡线以及弹性可弯曲线尖轨交叉渡线的受力变形规律进行了对比,分析了它们的异同点,给出高架桥上直线尖轨道岔取消缓冲区的检算算例;分析了影响桥上桥上无砟轨道直线尖轨交叉渡线受力和变形的主要因素:轨温变化幅度、扣件阻力、间隔铁、桥梁温度变化幅度、桥墩刚度、支座布置以及桥跨形式等,并初步尝试分析产生这些规律的原因。根据分析结果,对城市轨道交通桥上无砟轨道直线尖轨交叉渡线的设计提出了一些建议。更多还原

【Abstract】 Urban rail transit is the main part in urban public transport. It has many advantages such as large traffic volume, prompt, convenience, security and high efficiency. It is the primary way to solve the problem of traffic jam in large cities, and the situation of passenger traffic in large cities can be improved. Its function can’t be replaced by other means of communications. Therefore urban track transit is developed in many countries. Urban rail transit is different from national railway, so its own characteristics should be combined with when the track structure is researched. The research will be of great significance for the development of urban rail transit in our country.As a kind of important track structure, switch is technical puzzle of continuously welded rail (CWR) track across section. In our subway line, there are Single point, Single crossover, Scissors crossing, etc. No.7, 9, 12 switch is more often, and there are two forms of turning part: straight switch and curve switch. Although movable joint is at heel end of straight switch and the stability is not ideal, the damage is prone to occur, with low running speed on urban rail transit, the merits are long service life, small trip force and single-point traction, and its structure is simple, left and right hand turnout is universal, reduce the quantities of sparse on job site, so it is widely used on urban rail transit. As a kind of common equipment on throat near metro station, crossing track crossover can be joined in a butt to butt way, and the floor area can be decreased obviously, so it is widely used in our country for the existed railway and the railway in construction. Analysis the regularity stress and displacement, and research design theory and method, can be used to supervise turnout design, laying, maintenance and repair. So far, the regularities of stress and deformation have not been studied, so in this paper, research has been done on No.9 straight switch of crossing track crossover.Aiming at the characteristics of crossing track crossover in ballastless track of viaduct and railway on the ground in urban rail transit, using FEM of Beijing Jiaotong University, longitudinal and lateral coupling model of straight switch in crossing track crossover is established. The stress and deformation of crossing track crossover are analyzed. The results are compared with crossing track crossover in ballastless track on subgrade and the crossing track crossover of elastic flexible curve switch, and the common and different performances are analyzed. The calculation of cancelling buffer area for the condition of straight switch on bridge is proposed. The main influencing factors on stress and deformation of crossing track crossover in ballastless track on bridge are analyzed: rail temperature, fastening resistance, spacer block, bridge temperature, pier stiffness, layout of bearings, span types, etc, and tentative to analysis the reason of these regularity. Based on the analysis results, suggestions are put forward for design of crossing track crossover in ballastless track on bridge.更多还原