摘要
为保证衬砌结构具有合理的安全度,考虑冻胀水体、衬砌和围岩之间的共同作用特征,提出了约束冻胀模型和冻胀压力的理论计算式,并采用考虑围岩抗力的荷载-结构模型求解衬砌刚度分布.在此基础上,以结构安全度为度量指标,探讨了冻胀压力与衬砌刚度之间的关系.结果表明:等厚衬砌断面结构刚度在拱顶及仰拱中部较小,边墙部位较大;增大衬砌厚度使衬砌刚度增大,导致冻胀压力增大,同时也提高了衬砌承载能力;增大衬砌厚度导致的冻胀压力增大不如衬砌承载能力的提高显著,因此,增大衬砌厚度是提高衬砌抗冻能力的有效措施.
To ensure that lining has a suitable safety degree, a constrained frost heave model was proposed based on the interaction characteristic of frozen water body, lining and surrounding rock, and the corresponding analytical expression of frost heave pressure was give. A load-structure model was adopted to analyze the distribution of lining stiffness. In addition, the relationship between frost heave pressure and lining stiffness was investigated by taking the structure safety degree as an assessment index. The research result shows that the stiffness distribution of lining with identical thickness is uneven--lining stiffness is small at the arch crown of a tunnel and middle part of its inverted arch, while it is large along its side walls. The increase in the thickness of lining will make lining stiffness raise to result in a great frost heave pressure and the load-bearing capacity of lining increase significantly. As a result, increasing the thickness of lining is still an effective measure to improve the anti-freeze ability of cold regional tunnels.
出处
《西南交通大学学报》
EI
CSCD
北大核心
2009年第5期716-720,共5页
Journal of Southwest Jiaotong University
基金
西部交通建设科技项目(200431800029)
关键词
隧道工程
衬砌刚度
冻胀压力
约束冻胀模型
荷载-结构模型
结构安全度
tunnel engineering
lining stiffness
frost heave pressure
model of deformation constraints to frost heave
load-structure model
structural safety
