高速铁路无砟轨道现浇道床混凝土冻融破坏机理及寿命预测  

Freeze-thaw Damage Mechanism and Service Life Prediction of High-speed Railway Ballastless Cast-in-place Track Concrete

作　　者：董昊良 李化建[1,3] 杨志强 温家馨 黄法礼 王振 DONG Haoliang;LI Huajian;YANG Zhiqiang;WEN Jiaxin;HUANG Fali;WANG Zhen(China Academy of Railway Sciences,Beijing 100081,China;Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;State Key Laboratory for Track Technology of High-speed Railway,Beijing 100081,China)

机构地区：[1]中国铁道科学研究院,北京100081 [2]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [3]高速铁路轨道系统全国重点实验室,北京100081

出　　处：《铁道学报》2024年第8期112-120,共9页Journal of the China Railway Society

基　　金：国家自然科学基金(U1934206);中国铁道科学研究院集团有限公司科研项目(2021WR002)。

摘　　要：部分严寒地区的高速铁路无砟轨道现浇道床存在冻融粉化的问题。为揭示高速铁路无砟轨道现浇道床混凝土的冻融破坏机理并预测使用寿命,本文基于毛细吸附、静水压和损伤断裂理论,采用有限元分析方法研究现浇道床混凝土的冻融破坏机理。研究发现,孔隙水的冻胀作用是导致现浇道床混凝土表层发生冻融粉化的主要原因,现浇道床混凝土在冻融环境下呈现出由道床的四周及边角向中间区域逐渐剥落粉化的规律。通过分析环境最低温度在-24~-3℃、混凝土的吸水率为0.2%~1.0%时现浇道床的冻融破坏程度,建立无砟轨道现浇道床混凝土的寿命预测模型,预测不同吸水率和不同最低环境温度下现浇道床混凝土的冻融寿命,以期为寒区无砟轨道现浇道床混凝土的抗冻设计提供参考。The ballastless cast-in-place track in some severe cold regions suffers from freeze-thaw pulverization.In order to reveal the freeze-thaw damage mechanism and further to predict the service life of ballastless cast-in-place track concrete,in this paper,a finite element analysis method was used based on the capillary adsorption,hydrostatic pressure and damage fracture theory.The results show that the freeze-thaw effect of pore water is the main reason for the freeze-thaw pulverization of the surface layer of cast-in-place track bed concrete.Meanwhile,the surface freeze-thaw scaling firstly occurs in the edges and corners before developing to the center areas of ballastless cast-in-place track concrete under freeze-thaw conditions.By analyzing the degree of freeze-thaw damage to ballastless cast-in-place track under minimum environmental temperatures ranging from-24℃to-3℃and with concrete water absorption rates between 0.2%and 1.0%,this paper established a life prediction model for ballastless cast-in-place track concrete to predict the freeze-thaw life of ballastless cast-in-place track concrete under different water absorption rates and minimum ambient temperatures,aiming to provide reference for the freeze-resistant design of ballastless cast-in-place track concrete in cold regions.

关 键 词：高速铁路 道床板混凝土 冻融粉化 寿命预测 

分 类 号：U24[交通运输工程—道路与铁道工程]