摘要
高速铁路无砟轨道对于基础沉降变形特别敏感,地面沉降会显著影响路基上无砟轨道的受力变形及使用寿命,影响高速列车安全平稳运行。该文针对路基上双块式无砟轨道,基于有限元方法建立了梁-板-实体空间耦合模型,对地面不均匀沉降的幅值、范围及型式与双块式无砟轨道系统平顺性的关系开展了研究。结果表明:无砟轨道及路基各层沉降量随着地面沉降量增加基本成线性增加,支承层和路基表层间沉降差较大易出现离缝问题;地面沉降量20mm、沉降范围小于15m时,路基及轨道结构离缝现象明显,沉降范围大于15m时结构变形趋于平缓、轨面曲率半径增大;地面错台和折角型不均匀沉降均易导致无砟轨道及路基在折角点出现沉降差、结构离缝甚至开裂,折角值大小直接影响轨面平顺性。
A ballastless track is particularly sensitive to the deformation and settlement of its foundation soil. If the deformation of the foundation soil is too large, the stress and life of the ballastless track will be affected significantly. Moreover, the comfort and running stability of high-speed trains will be suffered. In this paper, for the double-block ballastless track on a roadbed, a beam-plate-solid spatial coupling model was established based on the finite element method. The research was conducted on the relationship between the regularity of a double-block track system and the amplitude, the scope and type of the ground uneven settlement. The results showed that the settlements of a ballastless track and its subgrade layers approximately showed a linear relationship with the increase of land subsidence. The settlement difference between the support layer and the surface layer of a subgrade was large enough to cause gaps between the two layers. The gap between a track and its subgrade was obvious when the land subsidence amplitude was 20 mm with a wavelength of 15 m. When the subsidence range was beyond 15 m, the deformation curves of structures became flat and the curvature radius of a rail surface became larger with the increase of land subsidence. Faulting and angular-type uneven settlements were more easily to cause a settlement difference, the gaps between a track structure and its subgrade, and even cracking at the knuckle point. The magnitude of the angle of an angular-type settlement directly affected the regularity of a rail surface.
出处
《工程力学》
EI
CSCD
北大核心
2014年第9期160-165,共6页
Engineering Mechanics
基金
国家自然科学基金项目(51108025
61134003)
中央高校基本科研业务费专项资金项目(2012JBZ011)
关键词
地面沉降
无砟轨道
轨道平顺性
有限元
高速铁路
land subsidence
ballastless track
track regularity
finite element
high-speed railway
