摘要
研究目的:季冻区高速铁路路基冻胀变形较为普遍,局部冻胀变形会给无砟轨道受力带来较大影响,甚至有可能带来结构层开裂。为此,本文建立高速铁路无砟轨道-路基冻胀耦合计算模型,以路基冻胀变形曲线作为冻胀变形的输入条件,分析路基冻胀变形波长和幅值对不同类型无砟轨道结构受力的影响,同时对CRTSⅢ型板式无砟轨道底座板凹槽限位优化为凸台限位方案以及下部设置沥青混凝土封闭层的影响进行分析。研究结论:(1)路基冻胀变形幅值越大,冻胀波长越小,无砟轨道结构层应力均越大;(2)双块式无砟轨道在路基冻胀下道床板和支承层应力较大,易产生开裂,不宜应用于季冻区;(3)底座板限位凹槽是CRTSⅢ型板式无砟轨道在基础冻胀变形下的受力薄弱环节,将其优化为凸台后,能够较大程度降低结构在基础变形下受力;(4)在CRTSⅢ型板式无砟轨道底座板下设置沥青混凝土层时,轨道板及底座板应力均有降低趋势,沥青混凝土层弹模越低,应力降低幅度越大;(5)本研究结论可为基础冻胀变形控制标准的制定和季冻区高速铁路无砟轨道的选型提供参考。
Research purposes： High - speed local subgrade frost heaving will bring a great cracking. In this respect, coupling models of railway subgrade frost heaving is very common in seasonal frozen area, impact on the ballastless track force, different types of ballastless track - s and may even lead to structural layer ubgrade system under subgrade frost heaving in high - speed railway are established. Based on the input conditions of subgrade frost heaving deformation curves, the effects of wavelength and amplitude of frost heaving deformation on the mechanical characteristics of different types of ballastless tracks are calculated and analyzed, the effect of the introduction of the sealing layer of asphalt concrete under the bed plate of CRTS II[ ballastless track and optimization effect of boss restrict on bed plate are both analyzed. Research conclusions： （ 1 ） The stress of the ballastless track structure increases as the increase of the amplitude of frost heaving deformation and the decrease of wavelength of frost heaving deformation. （2） The maximum longitudinal tensile stress of track slab and supporting layer is lager in hi - block ballastless track under subgrade frost heaving, the structure is prone to cracking, thus inappropriate to be applied to seasonal frozen areas. （3） The groove on the bed plate of CRTS m ballastless track is the bearing weakness under frost heaving deformation, after optimized to boss restrict, the structure force can be significantly reduced under the foundation deformation. （4） When the asphalt concrete layer is laid under the bed plate of CRTS Ⅲ ballastless track, the stress of the track slab and the bed plate simuhaneously shows a decreasing trend. The lower the elastic modulus of asphalt concrete is, the greater the decrease of stress is. （5） The conclusion of this paper can provide a reference for the development of subgrade frost heaving control standard and the selection of ballastless track fnr high - speed railway in seasonal frozen area.
出处
《铁道工程学报》
EI
北大核心
2017年第8期53-61,共9页
Journal of Railway Engineering Society
基金
中国铁路总公司科技研究开发计划课题(2015G006-H)
国家自然基金青年项目(41701088)
关键词
高速铁路
路基冻胀
无砟轨道
沥青混凝土
high -speed railway
subgrade frost heaving
ballastless track
asphah concrete
作者简介
赵国堂，1964年出生，男，研究员。
