Analysis of the Triggering Mechanism of a Loess Flowslide Induced by Water Canal Leakage(PDF)
《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]
- Issue:
- 2017年第01期
- Page:
- 135-142
- Research Field:
- 工程地质
- Publishing date:
Info
- Title:
- Analysis of the Triggering Mechanism of a Loess Flowslide Induced by Water Canal Leakage
- Author(s):
- XI Yu; LI Tong-lu; XING Xian-li
-
1. School of Geology Engineering and Geomatics, Chang an University, Xi ’an 710054, Shaanxi, China; 2. School of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
- Keywords:
- triaxial test; unsaturated seepage; pore water pressure; initiation mechanism; water canal leakage; Gaoloucun landslide
- PACS:
- P642.2
- DOI:
- -
- Abstract:
-
A lot of irrigation systems have been established to promote agricultural production since the 1970s in the loess area of China. At the same time, the loess landslides increase because of the canal leakage. Gaoloucun landslide, located in Hua county of Shaanxi, China, is one of those landslides. In order to find the initiation mechanism, based on unsaturated permeability theory, a finite element model of the pre failure slope was established to simulate the process of infiltration induced by water canal leakage. In order to find the stress state of slope failure, the loess samples were collected from the back edge of Gaoloucun landslide, and the triaxial tests of different stress paths under the saturation condition were performed. The triaxial tests include the stress path test on the possible sliding surface in the process of the increase of simulated water level, and the common load stress path test. The results show that because of the intermittent leakage, the perched water forms and rises in the slope, so that the pore water pressure in the saturated area increases, and the matric suction in the unsaturated area decreases; the rise of water level causes the initial deformation and damage, and the excess pore water pressure forms; the structure of loess soil at the top of the slope is loose, and the saturated water content is higher than the liquid limit, so that the saturated loess soil instantaneously changes from solid state to flow state, and the landslide is transformed into flowslide.
Last Update: 2017-01-20