铁道科学与工程学报2025，Vol.22Issue(1)：320-331,12.DOI:10.19713/j.cnki.43-1423/u.T20240489
考虑冻胀率梯度的季冻区非等压隧道不均匀冻胀解析
Uneven freezing analysis of non-isobaric tunnels in seasonally frozen regions considering gradient of frost heave rate
摘要
Abstract
Cold tunnels are susceptible to frost damage due to the severe influence of cold air under non-isobaric stresses,and the key to frost-resistant design for this purpose lies in the assessment of frost-heaving pressures and stress distributions during tunnel operation.Existing tests have revealed a significant gradient in the frost heave rate of the surrounding rock volume formed by the radial temperature field in cold tunnels.This paper considered the change of elastic modulus and frost heave rate caused by the deterioration of surrounding rock in freeze-thaw cycles.The uneven frost heave characteristics of surrounding rock were incorporated.The radial gradient of the frost heave rate formed by the tunnel temperature site was introduced.Complex function mapping bidirectional non-isobaric stress boundary conditions were employed,followed by proposing an analytical method for the dual uneven frost heave of non-isobaric tunnels in seasonally frozen regions.The model of this paper was temporarily degraded and effectively verified by engineering examples and existing theories.Parameter analysis indicates that introducing a gradient in frost heave rates significantly reduces stress within tunnels located in seasonally frozen regions.Under non-isobaric stress conditions,there are discrepancies in the stress variation rates of tunnels at different azimuths.The enhancement of the uneven frost heave characteristics of the surrounding rock gradually leads to a significant reduction in tunnel stress caused by the frost heave rate gradient.With the increase of lateral pressure,the radial and circumferential tunnel stresses increase,while the discrepancies in peak values and rates of change among tunnel stresses in different azimuths gradually diminish,having less impact on tunnel frost heaving pressures.Under freeze-thaw cycles,the discrepancies in stress distribution and the rate of stress change at different azimuths in the tunnel are roughly the same,but the deterioration of the surrounding rock results in an increase in tunnel stress.The magnitude of the increase in tunnel stress becomes significant with increasing freeze-thaw cycle counts.The results of this paper can offer theoretical guidance for the stress assessment and frost-resistant design of non-isobaric tunnels in seasonally frozen regions.关键词
冻胀率梯度/围岩不均匀冻胀/冻融循环/非等压应力/季冻区隧道Key words
frost heave rate gradient/uneven frost heave of surrounding rock/freeze-thaw cycles/non-isobaric stress/seasonally frozen tunnels分类
建筑与水利引用本文复制引用
李亮,陈嘉骏,赵炼恒..考虑冻胀率梯度的季冻区非等压隧道不均匀冻胀解析[J].铁道科学与工程学报,2025,22(1):320-331,12.基金项目
贵州省交通运输厅科技项目(2018123042) （2018123042）
中国铁路广州局集团有限公司科技研究开发计划项目(2021K094-Z) （2021K094-Z）
