【作者】 陈鹏；

【导师】 高亮； 许兆义；

【作者基本信息】 北京交通大学 ， 道路与铁道工程， 2009， 博士

【摘要】 无砟轨道由于具有稳定性好、维修工作量低及使用寿命长等突出特点,在日本、德国等高速铁路发达国家得到了广泛应用。我国目前在建的客运专线均大规模采用了无砟轨道结构,可见无砟轨道在我国有着相当广阔的发展前景。无砟轨道力学特性的研究,对于我国世界一流客运专线的建设,及铁路技术装备质量的大幅提具有十分重要的意义。本文在较全面的文献调研基础上,以新型Ⅱ型板式无砟轨道为主要研究对象,从静力学及动力学的角度,对无砟轨道的力学特性(包括路基上及桥梁上的无砟轨道系统)进行研究。本文主要开展了如下几方面的研究。1.总结了国内外无砟轨道的发展、应用情况及轨道结构力学的研究现状在对国内外无砟轨道的发展及应用情况进行广泛调研的基础上,重点对德国、日本无砟轨道的研发模式、无砟轨道的发展历程、典型无砟轨道型式的结构特点及优缺点等进行了较为系统的总结分析,并对我国无砟轨道的发展历程进行了阐述;总结了轨道结构静力学及动力学的研究现状,并对当前无砟轨道力学研究中的不足进行了分析。在此基础上拟定了本文的研究内容及创新点。2.建立了无砟轨道的静力及动力有限元分析模型采用ANSYS有限元平台建立了用于无砟轨道设计计算的三种静力有限元分析模型,即叠合梁模型、梁板模型及梁体模型,并对模型进行了对比分析及比选,明确了各模型的差别及使用条件。对ABAQUS运用于无砟轨道动力学仿真时的建模方法及主要涉及的问题进行了分析研究。在此基础上建立了路基及桥梁上无砟轨道动力有限元分析模型,并与遂渝线无砟轨道动力测试结果相比较,验证了建模方法的可靠性。3.研究了结构参数及基础变形(桥梁挠曲和路基不均匀沉降)对无砟轨道静力特性的影响采用建立的静力有限元分析模型,选取无砟轨道设计中重点关注的轨道板尺寸、砂浆弹性模量、支承层参数、扣件刚度、地基系数、预裂缝深度等设计参数,对无砟轨道的静力特性进行了参数影响分析。在此基础上对无砟轨道的设计提出了建议。研究了路基不均匀沉降条件下无砟轨道不同受力计算方法的差异,及纵向连接筋、路基不均匀沉降大小对于无砟轨道受力的影响;研究了桥梁挠曲条件下无砟轨道不同受力计算方法的差异,及纵向连接筋、连续梁固定支座上方的反弯作用、梁端转角、墩台差异沉降对无砟轨道受力的影响。在此基础上对基础变形条件下的无砟轨道设计提出了建议。4.研究了结构参数对无砟轨道动力特性的影响,对中高速条件下路基及桥梁上无砟轨道的动力响应进行了动力仿真分析采用建立的动力有限元模型,选取了扣件刚度、砂浆弹性模量、支承层弹性模量及基床参数等结构参数,对无砟轨道的动力特性进行了参数影响分析。在此基础上对无砟轨道的设计提出了建议。研究了中高速条件下车辆、无砟轨道、路基及桥梁系统的动力响应,结合国内外有关的动力评价指标及相应规定,对路基及桥梁上无砟轨道系统的动力响应水平进行了较为全面的评价。5.对比研究了不同纵向连接型式的无砟轨道力学特性静力方面,采用桥上无缝线路的分析方法,对不同纵向连接型式下的桥上无砟轨道纵向力进行了比较;动力方面,对路基、桥梁及路桥连接处不同纵向连接型式下的无砟轨道动力特性进行了比较。在此基础上对不同纵向连接型式的无砟轨道作出了评价。更多还原

【Abstract】 With excellent stability, low maintenance workload and ability of preserving the geometrical features, great attention has been paid to ballastless track by Japan, Germany and many other countries where high-speed railway is developed rapidly. At present, ballastless track is widely applied in passenger dedicated line under construction in our country, and it has broad prospect. The research on mechanical characteristics of ballastless track is of great significance for the world-class construction of railway in our country. Meanwhile, the research is important for the large scale improvement of technical equipment of railway line for passenger traffic. Based on comprehensive investigation of documents, and by taking Type II slab track as the main research object, systematic and deep research on ballastless track from static and dynamic aspect (including ballastless track system on bridge and subgrade) has been done within this paper. The main research contents are as follows:1.The development, application and research status of ballastless track are summarized.On the basis of extensive investigation on the development and application of ballastless track at home and abroad, a systematic summarization has been made with focus on the designing model, development course, the characteristics and advantages as well as disadvantages of the typical ballastless track in Germany and Japan. Moreover, a description of ballastless track development process in our country is given. With the summarization of static and dynamic research status, analysis of the deficiency of present ballastless track research is put forward. Thus the research contents and innovation points can be drawn up.2.Static and dynamic finite element analysis model of ballastless track are established.With the finite element platform of ANSYS, three static models are established for the calculation of ballastless track: composite beam model, beam slab model and beam body model. Comparison and selection is made among the three models, and the difference as well as application of each model have been analyzed.The modeling method with the use of ABAQUS and the relevant problems are discussed. The dynamic finite element models on bridge and subgrade are established, and the simulation results are compared with the dynamic test results of ballastless track in Sui-Yu Railway Line, thus the reliability of the modeling method can be verified. 3.Research is done on the influence of static characteristics of ballastless track caused by structure parameters and foundation deformation (bridge deflection and uneven settlement of subgrade).With the static finite element model, the main design parameters, including dimension of track plate, elastic modulus of mortar, parameters of HGT Layers, fastening stiffness, subgrade coefficient and the depth of pre-splitting crack are taken as the static parameters of ballastless track.Research is done on the difference of calculation methods under the condition of uneven settlement of subgrade. Analysis is made on stress influence caused by longitudinal reinforcement and uneven settlement of subgrade influence. Study is done on stress influence on ballastless track caused by longitudinal reinforcement, recurvation effect on the fixed bearings of the continuous beam, beam end rotation and differential settlement of bridge piers. Then a proposal is offered with respect to the design of ballastless track under the condition of foundation deformation.4. Research is done on the influence on dynamic characteristics of ballastless track caused by structure parameters. Dynamic simulation is carried out on ballastless track on subgrade and bridge under medium and high speed.Based on the finite element model, taking fastening stiffness, mortar elastic modulus,HGT Layers elastic modulus and subgrade coefficient as study parameters, analysis is done on dynamic characteristics of ballastless track. Suggestions are put forward for the design of ballastless track.Research is done on dynamic response of vehicle, ballastless track, subgrade and bridge system under medium and high speed. Combined with dynamic evaluation indexes and relevant regulations at home and abroad, an overall evaluation of dynamic response for the ballastless track on subgrade is given.5. Comparative study is done on mechanical characteristics of ballastless track with different longitudinal connection forms.From static aspect, using the method of continuously welded rail track on bridge, comparison of ballastless track on bridge with different connection forms is studied. From dynamic aspect, comparison is made on ballastless track on subgrad, bridge and the transitional section between road and bridge with different connection forms. Based on the above work, evaluation of the ballastless track with different connection forms is given.更多还原