| The Minjiang River Valley has a strong representation of the Quaternary glacialaccumulation body, which is widely distributed in the region valley of southwest China.With more and more roads, utilities and other human engineering activities carried outhere, human engineering activities effect was significantly increased with these largeice water accumulation bodies. Due to the accumulation body in a variety ofengineering has become a geological background conditions, the work becomes veryprominent significance of their engineering geological features and stability. HuanxiSlope this paper selects the subjects is a large ice water accumulation body, located inZagunao River right bank,Xuecheng town, Lixian city, Sichuan province, a volume ofabout1640Articles, belonging to the giant ice water accumulation body. Proceed fromthe deformation and failure characteristics of departure from the scene, to study theaccumulation of body by means of a large number of laboratory test, physicalsimulation, the limit equilibrium analysis and three-dimensional numerical simulationon the basis of the accumulation of body region and study area to analyze theengineering geological conditions. analysis and evaluation the accumulation body ofHuanxi slope stability. In this process, we get the following understanding:（1）Huanxi slope of the accumulation bodyin your area is the Zagunao valleylandforms, and the bottom elevation is about1550m, ridge elevation is about2600m.The slope of the accumulation body as a whole was the “fan-shaped " and relatively flaton both sides of slope in the space, the central steeper, with an average length of about675m, with an average width of about869m. The trailing edge height difference ofabout235m, with an average slope of20to25°and its axis is about330°to valleydirection.（2）Mineral composition and scanning electron microscopy analysis shows thatHuanxi slope’s mainly material composition is illite, content of54%to62%, followedby chlorite,content of14%to20%,and quartz content of13%to15%. This type of theaccumulation formatted in the late Pleistocene, influenced by the last glacial climatechange. （3）It can be seen from this article that involves the coarse granular soil triaxialspecimen, the material of Huanxi slope usually have higher shear strength. Indicators ofthe shear strength parameters, the C value is stronger sensitivity to water than the Φvalue. We can recognize that for experimental study of the Canadian coldpermafrost-like conditions: The beginning of the formation of the deposits of theglaciers (water), lower slope shear strength parameters relative to the current naturalconditions, as the climate warmer, glaciers, the slope of the moisture is graduallyincreased, shear strength decreased over time, as the climate became dry and warm, theslope of the moisture is gradually reduced, to the current natural state the shear strengthcome to the maximum.（4）Based on the similaritytheoryin the course of the study, we product scale of1:500physical model and get several awareness:①The failure deformation ofaccumulation gives priority to the towed local failure, this failure mode occupy thedominant position of the model deformation.②Irrigation accumulated on formatting ofholes in the body.③The affecting depth of crack is small in the accumulation slope, thecrack is mainly affect to the shallow stability.（5）Make use of the limit equilibrium theory to calculated on global and localstability of the accumulated slope. Due to material of accumulation slope is verysensitive to the water, thus stability in the natural state are very good, and in a stablestate. The B district deep sliding surface is owed to steady-state in the torrential rainoperating conditions; the other sections of accumulation slope stability are more in thestable state.（6）In this paper, the natural, heavy rain, the stress and deformationcharacteristics of accumulation slope were simulated by means of three-dimensionalnumerical simulation (FLAC3D.), the results show that:①Accumulation have a certainarea of the plastic zone distribution in the natural state and torrential rain state.②In thecondition of natural and heavy rain, edge shear stress concentration zone did not formthe continuous through shear plane and did not affect the accumulation body overallstability.③Model displacement tracking point data show that the main deformationand failure mechanisms are traction rear deformation in deformation of the body.④Thearea A and area B of accumulation slope, the junction exist local strong deformationzone, the displacement of up to18cm in rainstorms state. |
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