Analysis on the effect of freeze-thaw on landslide prevention projects in seasonal frozen soil area
-
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。
Abstract: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.
-
Key words:
- freeze-thaw /
- Sichuan-Tibet railway /
- seasonal frozen region /
- landslide /
- anchor
-
表 1 锚索监测数据[19]
Table 1. Monitoring data of anchor cables[19]
编号 锁定锚固力
/kN最大锚固力
/kN最大增长率
/%稳定值
/kN339# 482 605 25.52 600 345# 638 902 41.38 620 357# 630 920 46.03 600 358# 805 1110 37.89 950 -
[1] 薛翊国, 孔凡猛, 杨为民, 等. 川藏铁路沿线主要不良地质条件与工程地质问题[J]. 岩石力学与工程学报,2020,39(3):445 − 468. [XUE Yiguo, KONG Fanmeng, YANG Weimin, et al. Main unfavorable geological conditions and engineering geological problems along Sichuan-Tibet railway[J]. Chinese Journal of Rock Mechanics and Engineering,2020,39(3):445 − 468. (in Chinese with English abstract)
[2] 梁波, 王家东, 严松宏, 等. 多年冻土地区L型挡土墙土压力(冻胀力)的分析与试验[J]. 冰川冻土,2002,24(5):628 − 633. [LIANG Bo, WANG Jiadong, YAN Songhong, et al. Experiment and analysis of the earth pressure (frost heaving forces) on L-type retaining wall in permafrost regions[J]. Journal of Glaciolgy and Geocryology,2002,24(5):628 − 633. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-0240.2002.05.027
[3] 梁波, 王家东, 葛建军, 等. 青藏铁路L型挡土墙的土压力实测与分析[J]. 岩土工程学报,2004,26(5):627 − 631. [LIANG Bo, WANG Jiadong, GE Jianjun, et al. Testing and analysis of earth pressure about L type retaining wall in Qinghai-Tibet railway[J]. Chinese Journal of Geotechnical Engineering,2004,26(5):627 − 631. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-4548.2004.05.011
[4] 汪恩良, 钟华, 孙景路, 等. 加筋土挡墙冻融试验研究[J]. 岩土工程学报,2010,32(2):265 − 270. [WANG Enliang, ZHONG Hua, SUN Jinglu, et al. Experimental study on reinforced retaining walls suffering freeze-thaw cycling[J]. Chinese Journal of Geotechnical Engineering,2010,32(2):265 − 270. (in Chinese with English abstract)
[5] 赵坚, 那文杰, 曹顺星. 季节冻土区挡土墙抗冻结构设计方法[J]. 黑龙江交通科技,2001,24(5):14 − 16. [ZHAO Jian, NA Wenjie, CAO Shunxing. Design of antifreezing structure for retaining walls in seasonal frost regions[J]. Communicatios Science and Technology Heilongjiang,2001,24(5):14 − 16. (in Chinese with English abstract) doi: 10.3969/j.issn.1008-3383.2001.05.008
[6] ZHANG Y, DONG J H, DONG X G, et al. Analysis of freezing and thawing of slope improved by soil nailing structure in seasonal frozen soil region[J]. Rock and Soil Mechanics,2017,38(2):574 − 582.
[7] 赵延凯, 彭然, 周加伟, 等. 季节性冻土深基坑支护技术研究[J]. 建筑结构,2011,41(7):119 − 122. [ZHAO Yankai, PENG Ran, ZHOU Jiawei, et al. Investigation on technology of retaining and protection for seasonal frozen soil deep foundation pit[J]. Building Structure,2011,41(7):119 − 122. (in Chinese with English abstract)
[8] 郭红仙, 宋二祥, 陈肇元. 季节冻土对土钉支护的影响[J]. 工程勘察,2006,34(2):1 − 6. [GUO Hongxian, SONG Erxiang, CHEN Zhaoyuan. Soil nailing under the influence of the seasonal frozen soil[J]. Journal of Geotechnical Investigation & Surveying,2006,34(2):1 − 6. (in Chinese with English abstract)
[9] STOCKER M F, RIEDINGER G. The bearing behavior of nailed retaining structures[C]// Design and Performance of Earth Retaining Structures: Proceedings of a Conference Sponsored by the Geotechnical Engineering Division of the American Society of Civil Engineers. New York, June 18-21, 1990, edited by Philip C. Lambe and Lawrence A. Hansen: 612-628.
[10] KINGSBURY D W, SANDFORD T C, HUMPHREY D N. Soil nail forces caused by frost[J]. Transportation Research Record:Journal of the Transportation Research Board,2002,1808(1):38 − 46. doi: 10.3141/1808-05
[11] LONG N T, T LIVET M, BOUTONNCT, et al. Repair of a reinforced earth wall[C]//Proc. Interactional Conference on Case Histories in Geotechnical Engineering, University of Missouri-Rolla, 1984: 335-346.
[12] 李宗龙. 川西高原川藏交通廊道季节性冻土分布规律及处置措施[D]. 成都: 西南交通大学, 2013.
LI Zonglong. Distribution regularity and disposal measures of seasonal frozen soil of Sichuan-Tibet transportation corridor in west Sichuan plateau[D]. Chengdu: Southwest Jiaotong University, 2013. (in Chinese with English abstract)
[13] 中华人民共和国交通运输部. 季节性冻土地区公路设计与施工技术规范: JTG/T D31-06—2017[S]. 北京: 人民交通出版社, 2017.
Ministry of Transport of the People's Republic of China. Technical Specifications for Design and Construction of Highway in seasonal Frozen Soil Region: JTG_T D31-06-2017[S]. Beijing: People's Communications Publishing Co. Ltd., 2017. (in Chinese)
[14] 张誉,蒋利学,等. 混凝土结构耐久性概论[M].上海:上海科学技术出版社, 2003:105-117.
ZHANG Yu,JIANG Lixue, et al. Durability of concrete structure [M]. Shanghai:Shanghai Science and Technology Press, 2003:105−117. (in Chinese)
[15] 董旭光, 董建华, 何天虎, 等. 多年冻土边坡的水热力耦合分析及软件开发[J]. 中国地质灾害与防治学报,2020,31(4):77 − 84. [DONG Xuguang,DONG Jianhua,HE Tianhu,et al. Coupling analysis and software development of moisture-heat-stressfields of permafrost slope[J]. The Chinese Journal of Geological Hazard and Control,2020,31(4):77 − 84. (in Chinese with English abstract)
[16] 张遂, 匡航, 靳占英, 等. 高含水量冻粉黏土应力-应变曲线特性的试验研究[J]. 水文地质工程地质,2020,47(5):116 − 124. [ZHANG Sui, KUANG Hang, JIN Zhanying, et al. An experimental study of the stress-strain characteristics of frozen silty clay with high moisture content[J]. Hydrogeology & Engineering Geology,2020,47(5):116 − 124. (in Chinese with English abstract)
[17] 齐子萱, 周金龙, 季彦桢, 等. 西北内陆盆地降水入渗补给季节性变化—以新疆昌吉地下水均衡试验场为例[J]. 水文地质工程地质,2020,47(5):12 − 20. [QI Zixuan, ZHOU Jinlong, JI Yanzhen,et al. Seasonal variationin recharge of infiltration from precipitation for the inland basins of northwestern China: taking the Changji groundwater balance test station in Xinjiang as an example[J]. Hydrogeology & Engineering Geology,2020,47(5):12 − 20. (in Chinese with English abstract)
[18] 中华人民共和国住房和城乡建设部, 中华人民共和国国家质量监督检验检疫总局. 水工建筑物抗冰冻设计规范: GB/T 50662—2011[S]. 北京: 中国计划出版社, 2012.
Ministry of Housing and Urban-Rural Development of the People's Republic of China, General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China. Code for design of hydraulic structures against ice and freezing action: GB/T 50662—2011[S]. Beijing: China Planning Press, 2012. (in Chinese)
[19] 何伟. 西藏自治区国道318线田妥镇滑坡机理及防治技术研究[D]. 重庆: 重庆交通大学, 2012.
HE Wei. Research of the Tibet autonomous region national Highway 318 Line of the landslide mechanism and the field prevention and control technology[D]. Chongqing: Chongqing Jiaotong University, 2012. (in Chinese with English abstract)