路基冻胀-融化-沉降循环作用下高速铁路板式无砟轨道伤损演化与变形分析  

Analysis of Damage Evolution and Deformation of High-speed Railway Ballastless Slab Track under the Effect of Subgrade Frost Heaving-Melting-Settlement Cycle

作　　者：林士财 LIN Shicai(Shaanxi Railway and Underground Traffic Engineering Key Laboratory(FSDI),Xi'an 710043,China)

机构地区：[1]陕西省铁道及地下交通工程重点实验室(中铁一院),西安710043

出　　处：《铁道标准设计》2020年第8期20-26,共7页Railway Standard Design

基　　金：国家自然科学基金委员会与神华集团有限公司联合资助项目(U1261113);高等学校博士学科点专项科研基金资助项目(20100162110022);江西省教育厅科技资助项目(GJJ151173,GJJ151175)。

摘　　要：为研究路基冻胀-融化-沉降循环作用下,无砟轨道结构的伤损演化规律和变形特性,基于有限单元法及混凝土塑性损伤模型,建立路基上单元板式无砟轨道静力分析模型。计算结果表明:(1)小波长条件下,底座板在冻胀过程中易在幅值两侧对应第一块轨道板的板端萌生损伤,但随波长的增加,轨道结构塑性损伤得以缓解;(2)路基冻胀-融化-沉降循环作用引起轨道不平顺,其幅值呈增加-减小-反向增加的变化趋势,但波长较小时,反向增加的幅度极小;(3)路基回落过程中,轨道结构存在部分残余变形;(4)底座板与基床表层间的离缝呈张开-闭合-张开的循环性变化规律,离缝宽度随路基变形幅值的增大而增大;(5)路基变形波长对离缝宽度及纵向分布有极大影响。Based on the finite element method and the concrete plastic damage model, a static analysis model of the unit slab track on the subgrade is established to study damage evolution and deformation characteristics of the ballastless track structure under the effect of subgrade frost heaving-melting-settlement cycle. Results indicate that: 1) the base plate is likely to be damaged at the end of the first slab on both sides of the amplitude in the process of frost heaving under the condition of small wavelength;however, the plastic damage of the track structure is alleviated with increasing wavelength. 2) The track irregularity is generated by the effect of subgrade frost heaving-melting-settlement cycle, and its amplitude tends to be increased, decreased and increased reversely;but when the wavelength is small, the magnitude of the reverse increase is extremely small. 3) There is partial residual deformation in the track structure during the subgrade melting process. 4) The seam between the base plate and the bedding surface changes cyclically in the pattern of open-close-open. The width of the seam increases as the amplitude of the subgrade increases. 5) The deformation wavelength of the subgrade has a great influence on the width and longitudinal distribution of the seam.

关 键 词：铁道路基 无砟轨道 塑性损伤 冻胀 融化 沉降 受力 变形 高速铁路 

分 类 号：U213.2[交通运输工程—道路与铁道工程]