摘要
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,研究路基冻胀—融化—沉降循环作用下,无砟轨道结构的受力和变形特性及伤损演化规律。研究结果表明:在路基冻胀—融化—沉降循环作用下,轨道板和底座板在冻胀过程中逐渐形成塑性损伤,且轨道板的塑性损伤早于底座板的塑性损伤;在融化回落及沉降阶段,轨道板的损伤状态相对稳定,而底座板在距其端部1/3位置处逐渐形成第二塑性区;在路基冻胀—融化—沉降循环作用下,将不可避免地引起轨道不平顺,轨道不平顺幅值呈增加—减小—反向增加的变化趋势;当路基回落至初始状态时,轨道结构存在部分残余变形;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。该研究可为高速铁路无砟轨道养护维修提供参考。
Based on the finite element method and the concrete damaged plastic model, a static analysis model of the unit slab ballastless track on the subgrade was established to study the stress and deformation characteristics and damage evolution of ballastless track structures under the effect of subgrade frost heaving-melting-settlement cycle. The results show that under the effect of subgrade frost heaving-melting-settlement cycle, the plastic damage is developed gradually in the slab and the base plate during the frost heaving process, and the plastic damage of the slab is earlier than that of the base plate. In the phase of meltdown and settlement, the damage state of the slab is relatively stable, while the base plate forms a second plastic zone gradually at the 1/3 position from its end, the track irregularity will be formed inevitably under the effect of subgrade frost heaving-melting-settlement cycle, and the amplitude of the track irregularity has a changing trend which is increased-decreased-increased reversely. There is partial residual deformation in the track structure when the subgrade returns to its initial state. The seam between the base plate and the bedding surface changes cyclically with a trend of opened-closed-opened. The study can provide reference for the maintenance and repair of ballastless track of high?speed railway.
作者
向俊
林士财
余翠英
袁铖
陈林
杨海明
XIANG Jun;LIN Shicai;YU Cuiying;YUAN Cheng;CHEN Lin;YANG Haiming(School of Civil Engineering, Central South University, Changsha 410075, China;School of Science, East China Jiaotong University, Nanchang 330013, China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2019年第8期2043-2052,共10页
Journal of Central South University:Science and Technology
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)
牵引动力国家重点实验室开放课题资助项目(TPL0901,TPL1214)
江西省教育厅科技资助项目(GJJ151173,GJJ151175)~~
关键词
铁道工程
无砟轨道
塑性损伤
冻胀
融化
沉降
受力
变形
railway engineering
ballastless track
plastic damage
frost heaving
melting
settlement
stress
deformation
