【作者】 李娟；

【导师】 刘学毅；

【作者基本信息】 西南交通大学 ， 道路与铁道工程， 2016， 硕士

【摘要】 铁路路基的冻胀很大程度上影响了既有铁路提速。高速铁路路基的不均匀冻胀会造成线路上拱变形超限,影响线路平顺度和高速铁路运营,严重时造成铁路运营安全隐患。而目前已有的资料中,关于高速铁路无砟轨道结构受路基冻胀影响的研究还不够完善。哈大高速铁路线路是我国较为典型的严寒地区铁路,该线路上的轨道类型为CRTSⅠ型板式无砟轨道结构,本文通过对国内外铁路路基冻胀有关资料的分析和整理,结合哈大高铁路基冻胀的特点,针对高速铁路板式轨道结构受路基冻胀的影响进行了理论分析。主要内容如下：(1)分析了铁路基础变形形式和路基冻胀特点,分析得到了铁路路基冻胀变形模拟曲线以及路基冻胀变形作用于轨道结构时的加载方法。(2)运用有限元方法和软件,以CRTS Ⅰ型板式无砟轨道为研究对象,建立无砟轨道路基冻胀影响计算模型,在考虑冬季低温气候条件、列车荷载共同作用的情况下,分别计算路基冻胀峰值对应于板式轨道底座板的板中位置和板缝位置时两种情况。计算结果表明板中冻胀比板缝冻胀所引起的的轨道结构位移小,但轨道应力大。(3)对不同冻胀峰值和冻胀波长的路基冻胀条件下轨道结构的变形和受力进行计算,通过对轨道结构位移、层间离缝、纵向变形影响范围、第一主应力等因素的计算结果进行分析,得出轨道应力和位移最大值主要受冻胀峰值的影响,而轨道沿线路纵向的应力和位移的变化趋势主要受冻胀波长的影响。根据计算结果提出轨道结构破坏时对应的路基冻胀限值。更多还原

【Abstract】 Railway subgrade frost heaving has a great impact on the speed-increase of existing railway lines. Differential subgrade frost heaving of high-speed railway can cause unreasonable deformation of line arch and cause safety hazard of railway operation. Research is still not complete about the influence of frost heaving on high-speed railway ballastless track structure in current information.Harbin-Dalian high-speed railway lines are more typical of cold regions railroad track, which line type is CRTS I slab track structure. Combined with the subgrade frost heaving characteristics of Harbin-Dalian high-speed railway, the article analyse theoretically the effect of subgrade frost heaving on high-speed rail slab track structure based on the analysis and collationg of domestic and international rail frost heaving information. The main contents are as follows:(1) Deformation type of railway subgrade and the characteristics of subgrade frost heaving are analyzed, which acquire the simulated curves of railway subgrade frost heaving and the loading method when frost heaving deformation acts on the track structure.(2) Finite element method and software are used to study CRTS I Slab track, set up the calculation model of ballastless subgrade frost affect, and calculate frost heave peak at slab middle and slab edge in consideration of the low temperature in winter and the train load conditions. The results show that the frost heaving displacement at slab middle is smaller than the slab edge, but track stress is bigger.(3) Track structure deformation and stress are calculated under conditions of subgrade frost heaving which has different heaving peaks and wavelengths; the calculation results of different factors, such as track structure displacement, interlayer seam, longitudinal deformation range and the first main stress factor are analyzed; the results shows that maximum stress and displacement of track are mainly affected by frost peak and the trends of track longitudinal stress and displacement are mainly affected by frost wavelength; track structure frost heaving limits are put forward when the track structure are damaged according to the calculation results.更多还原