季节性冻土区滑坡防治工程的冻融效应分析  

Analysis on the effect of freeze-thaw on landslide prevention projects in seasonal frozen soil area

作　　者：杨栋[1] 王全成[1] 姜昭群[1] YANG Dong;WANG Quancheng;JIANG Zhaoqun(The Institute of Exploration Technology,GAGS,Chengdu,Sichuan 611734,China)

机构地区：[1]中国地质科学院探矿工艺研究所,四川成都611734

出　　处：《中国地质灾害与防治学报》2021年第6期82-89,共8页The Chinese Journal of Geological Hazard and Control

基　　金：中国地质调查局地质调查项目“藏东昌都地区城镇灾害地质调查”(DD20190644);国家重点研发计划项目“膨胀土滑坡和工程边坡防护工程健康诊断和快速修复”(2019YFC1509904)。

摘　　要：川藏铁路规划线路穿越青藏高原东缘高寒带岛状山地冻土区,冻融环境相对复杂。文章通过对川西地区及藏东昌都地区G317、G318沿线滑坡防治工程25处典型案例进行调查,总结冻融条件下滑坡防治工程的破坏形式及受力机理,探讨了水平冻胀力、法向冻胀力的计算方法及其对挡墙、桩间板、排水沟等的影响,计算结果表明水平冻胀力远大于主动土压力,认为开放式冻胀较封闭式冻胀对防治工程的影响更大;阐明了冻胀融沉对锚索工程的影响,提出使用基于蓄能消能系统的锚索结构;探讨了季节性冻土区滑坡防治材料抗冻等级选择方法及减缓冻融效应的措施及建议,为川藏铁路沿线滑坡治理工程及拟建施工便道的边坡支护提供参考。The planned route of the Sichuan-Tibet railway passes through the frozen soil on the eastern edge of the Qinghai-Tibet Plateau.The freezing-thawing environment is relatively complicated.More than 25 typical cases of landslide control projects along G317 and G318 in western Sichuan and Qamdo areas were investigated.The failure modes and force mechanisms of the projects under freeze-thaw conditions were summarized.The calculation method of horizontal frost heave force was discussed.The effects of horizontal frost heave retaining walls and drainage ditches were explored.The calculation results show that the horizontal frost heave force is much larger than the active earth pressure.The effects of frost heave and thawing on anchor cable engineering are clarified.It is considered that the effect of open frost heave on control engineering is greater than that of closed frost heave.Methods of material antifreeze grade and measures to reduce freeze-thaw effect were proposed.It can be used as a reference for landslide management projects along the Sichuan-Tibet railway.

关 键 词：冻融作用 川藏铁路 季节性冻土 滑坡 锚索 

分 类 号：P642.22[天文地球—工程地质学] X43[天文地球—地质矿产勘探]