坡脚开挖诱发古滑坡复活的机制分析
Research on the Mechanism of the Ancient Landslide Resurrection Triggered by Slope Toe Excavation
-
摘要: 黄土地区存在许多古滑坡体，由于滑后土体土质疏松，裂隙发育，在坡脚开挖作用下极易发生变形破坏，造成大量财产损失，同时也对开挖施工安全构成了极大的威胁，因此对坡脚开挖诱发古滑坡复活的失稳机制的研究十分迫切和必要。以延安市王窑村滑坡为例，通过室内试验分析了三轴应力环境下围压、含水量对土体变形破坏的影响，并运用数值模拟研究了开挖过程中最危险滑面上的应力及强度变化趋势，揭示了坡脚开挖诱发古滑坡复活的变形破坏机理。研究结果表明：坡脚开挖改变了坡体中下部的应力分布，抗滑段土方开挖减小了滑坡抗滑力，增大了下滑力，最终滑坡下滑力超过抗滑力，导致古滑坡复活。Abstract: There are many ancient landslides in the loess area. The slip mass of ancient landslide is incompact and fissured, it's easy to slide under the slope toe excavation. The landslides triggered by slope toe excavation have caused a great quantity of economic losses and have posed an enormous threat on safety during construction; hence there are practical significances to study on its mechanism. Focusing on Wangyao Village landslide in Yan'an, the effect of confining pressure and moisture to loess is obtained by triaxial test, the stress and strength change on the most dangerous slip surface during excavation are studied and the deformation and fracture mechanism of the ancient landslide resurrection are revealed based on numerical analysis. The results show that excavating on the toe of slope changed the stress distribution and the shear stress in middle and lower part of slope, making the sliding resistance decreased and sliding force increased, in the end, the sliding force exceeds the sliding resistance and then the landslides occurred.
-
-
张茂省, 孙传尧, 校培喜, 等.延安市宝塔区地质灾害详细调查示范[J].西北地质, 2007, 40(2):29-55. Zhang Maosheng, Sun Chuanyao, Xiao Peixi, et al.A Demonstration Project for Detailed Geo-hazard Survey in the Baota District, Yan'an[J]. North Western Geology, 2007, 40(2):29-55(in Chinese).
缪卫东, 侯连中.西安市白鹿塬滑坡发生时间预测研究[J].西北地质, 2003, 36(4):90-95.
Miao Weidong, Hou Lianzhong.Time prediction study on occurring of landslides in Bsiluyuan, Xi'an.[J]. North Western Geology, 2003, 36(4):90-95(in Chinese ).
雷祥义.黄土高原地质灾害与人类活动[M].北京:地质出版社, 2001.
Lei Xiangyi. Geological hazards and human activity on the loess plateau[M]. Geological Press, Beijing, 2001(in Chinese).
陈春利.延安地区人工开挖黄土边坡的变形破坏机理研究[D].西安:长安大学, 2011.
Chen Chunli. Study on the deformation and failure mechanism of excavated loess slope in Yan'an[D].Xi'an:Chang'an University(in Chinese).
李明, 张嘎, 胡耘, 等.边坡开挖破坏过程的离心模型试验研究[J].岩土力学, 2010, 31(2):366-370.
Li Ming, Zhang Ga, Hu Yun, et al. Centrifuge model tests on excavation-induced failure of slopes[J]. Rock and Soil Mechanics, 2010, 31(2):366-370(in Chinese).
张季如.边坡开挖的有限元模拟和稳定性评价[J].岩石力学与工程学报, 2002(6):843-847.
Zhang Jiru. Finite Element Simulation And Stability Analysison Slope Excavation[J]. Chinese Journal of Rock Mechanics and Engineering, 2002(6):843-847(in Chinese).
张志龙, 李天斌, 赵其华.二郎山和平沟滑坡成因分析及稳定性评价[J].西北地质, 2003, 36(4):84-89.
Zhang Zhilong, Li Tianbin, Zhao Qihua.The cause and the stability evalution of Hepinggou landslide in Erlang Mountain[J]. North Western Geology, 2003, 36(4):84-9(in Chinese ).
刘祖典.黄土力学与工程[M].西安:陕西科学技术出版社, 1997.
Liu Zudian. Mechanics of loess and engineering[M]. Shaanxi Science and Technology Press, Shaanxi, 1999(in Chinese).
Lee W.ABRAMSON, Thomas S.LEE, Sunil SHARMA, et al.Slope Stability and Stabilization Methods, 2nd Edition[M].New York: A Wiley-interscience Publication, 2001. Peter Dunlop, James M. Duncan.Development of Failure around Excavated Slopes[J].Journal of the Soil Mechanics and Foundations Division, 1970, 96(2): 471-493.
Wang Fawu, Zhang Yeming, Wang Gonghui, et al. Deformation Features of Shuping Landslide Caused By Water Level Changes In Three Gorges Reservoir Area, China[J].Chinese Journal of Rock Mechanics and Engineering, 2007, 26(3):509-517.
-
计量
- 文章访问数: 2940
- PDF下载数: 2126
- 施引文献: 0
下载: