The Study Of Centrifuge Model About Homogeneous Soil Slope Deformation Failure Process And Characteristics

In recent years, landslide disasters occur frequently, it is necessary to establish its monitoring and warning system.The study on the failure process and deformation characteristics of landslides is very important for monitoring and early warning for landslides. The geotechnicalcentrifuge testing and numerical simulation were conducted to study the homogeneous slope deformation and failure process. In order to study the failure process and deformation characteristics of landslides,the geotechnicalcentrifuge testing and numerical simulation were conducted to study the homogeneous slope deformation and failure process. First, we can simulated the conditions specified size homogeneous soil by centrifugal model test, analyzed the failure process, deformation and failure characteristics, deformation and failure mechanisms. After completion of centrifuge model test, using FLAC3 D software to simulate different sizes conditions(slope angle, the slope height variation) homogeneous soil slope deformation and failure under the law. On the basis of a series of simulation,weanalyzed the failure process,deformation and failure characteristics, deformation and failure mechanisms ofthe heterogeneous soil slope.Now this paper, the main results achieved as follows:(1)In the process of centrifugal test, homogeneous slope deformation and failure process can be blanket is as follows: ①Local deformation and failure stages; ②Deformation damage extension stage; Deformation damage extension stage; ③Deformation and failure development through phase. Difference is that a homogeneous soil slope of different slope type of local area, the influence of the deformation area at the beginning of deformation, the mechanical properties of different deformation. Specific: when high slope height, slope Angle is bigger(H>40cm, α>40°),first appeared in the trailing edge peak deformation of slope body, in the presence of the deformation caused by sexual pulling force. Tension, with the increase of centrifugal acceleration peak area will appear crack, tensile fracture extension, at the same time to the Y direction and Z direction at the same time, leading edge slope foot appear a certain amount of stress concentration phenomenon. Further acceleration, deformation and failure area along the slope facing slope foot are extended by the peak, the slope foot appear a small amount of shear failure. In the end, the cracking area and leading edge shear deformation area; when the high slope is Low, slope Angle is small(H<40cm, α<40°),Slope in front slope toe first occur deformation, deformation is mainly caused by shear force. With centrifugal acceleration, the shear deformation increase, pull the back of the deformation of soil, with further increase of the centrifugal acceleration, the influence of deformation area increased gradually to the top. Overall damage model of centrifugal acceleration values are between 100 ~ 150 g.(2) Stress distribution characteristics of homogeneous soil slope as: table slope stress value is bigger, prone to deformation and failure; Almost all of the minimum principal stress concentration on the top of the slope. The maximum main stress concentration appears on top of a slope or the slope foot; Slope foot appear stress concentration happens high Angle or under the condition of high slope type.(3) Homogeneous slope deformation and failure characteristics: a leading edge in great cut out of the deformation of slope foot(X direction), and almost no displacement in the Y direction; At the top near the slope, it mainly happens on the Y direction of displacement of X direction occurs relatively small displacement caused by sexual force; From top to toe, the displacement on the X direction were increased, the Y direction of the displacement showed a trend of decrease; As change steep increase the high slope, slope Angle, the overall displacement increases, increase of tensile force and deformation area, dust is visible along the Z direction and development of cracks, slope toe out of shear failure. Slope body appears the shear strain increment, a potential slip surface(zone).(4)By monitoring point displacement analysis shows:slope table first appeared significant deformation, when the lower slope high slope angle is small, the deformation occurs mainly in shallow slope.With the slope height, slope angle increases, the slope table displacement continues to increase, the depth of the slope to slope deformation continues to increase in vivo expansion. With the slope height, slope angle is further increased more, after slope failure depth deeper edge deformation, deformation of the slope there is a greater part of the regional body to adjust.(5) By analyzing the deformation and failure mechanism of homogeneous soil slope, the failure modes can be classified into two classes: ① "cracking, creep, cut" type, mainly in high slope height, slope Angle is bigger slope type. The first type of deformation and failure process in the formation of cracks, and then in the slope toe edge slope top place occurrence creep shear effect, the final "cut" in the middle of the soil, forming a complete sliding surface, slope instability. Due to the expansion of cracks slope to the slope body is deeper, when this kind of slope failure is relatively large, medium-sized landslide belongs to, look from the mechanics course is similar to the type of landslide.②creep, cracking, shear, mainly in the high slope in the lower slope, slope Angle smaller type. That first struck at the leading edge slope foot behind the creep shear function, and then drive or cracking slope, the final shear failure occurrence, form continuous sliding surface, slope instability as a whole.