牵引式滑坡变形演化的模型试验研究

发布时间：2018-08-17 14:43

【摘要】：关于牵引式滑坡变形演化方面的研究,现有文献很少,目前大家普遍接受的观点是:牵引式滑坡一般是由于坡脚冲蚀或开挖等因素引起,综合的不利因素导致牵引区滑体失稳,随着变形的增大,牵引区后缘支撑减弱甚至临空,牵引区滑体后缘斜坡体也发生变形失稳,滑坡体向后向上发展,最终滑动面逐渐贯通形成大型滑坡体;目前就牵引式滑坡裂缝分类及演化阶段划分并没有统一的标准。物理模型试验是进行边坡研究的重要手段,可以用来模拟各种工况。本研究运用自行设计的牵引式滑坡模型试验装置进行了不同条件下的牵引式滑坡物理模型试验,试验借助了相机、三维激光扫描仪及应力采集装置对试验过程进行了记录,经分析,主要结论如下:(1)设计的模型试验方案实现了牵引式滑坡的分期破坏过程,通过试验,得到了每组试验具体裂缝产生的顺序及裂缝演化过程,验证了所设计牵引式滑坡模型试验的可行性及合理性,同时验证了利用该试验方法进行牵引式滑坡支护措施优选的可行的。(2)通过分析裂缝贯通比随时间变化规律,本文将牵引式滑坡变形演化过程分为5个阶段:初始变形阶段、匀速变形阶段、加速变形阶段、稳定变形阶段及整体滑动阶段。(3)本文对牵引式滑坡各类型滑坡裂缝在时间及空间分布规律进行了总结,同时对各试验演化阶段时间占试验时间的百分比进行了统计,结合裂缝贯通比-时间曲线,从滑坡模型试验的角度出发,得出了可以将裂缝贯通比达到40%作为滑坡临滑预警值的结论。
[Abstract]:There are few literatures on the deformation evolution of traction landslide. At present, it is generally accepted that the traction landslide is generally caused by erosion or excavation at the foot of the slope, and the comprehensive unfavorable factors lead to the instability of the sliding body in the traction area. With the increase of deformation, the support of the rear edge of the traction area is weakened or even empty, the slope body of the rear edge of the traction area is also deformed and unstable, the landslide body develops backward and upward, and finally, the sliding surface gradually passes through to form a large landslide body. At present, there is no uniform standard for the classification and evolution stage classification of traction landslide fractures. Physical model test is an important method for slope research and can be used to simulate various working conditions. In this study, the physical model test of traction landslide was carried out under different conditions with the help of a camera, a 3D laser scanner and a stress acquisition device, and the test process was recorded with the help of a self-designed tractive landslide model test device, and the experiment was carried out with the aid of a camera, a three-dimensional laser scanner and a stress acquisition device. Through analysis, the main conclusions are as follows: (1) the designed model test scheme realizes the stage failure process of the traction landslide. Through the tests, the sequence of concrete cracks and the evolution process of the cracks in each group of tests are obtained. The feasibility and rationality of the designed traction landslide model test are verified, and the feasibility of optimal selection of the traction landslide supporting measures by using the test method is verified. (2) by analyzing the variation law of fracture through-through ratio with time, In this paper, the process of deformation evolution of traction landslide is divided into five stages: initial deformation stage, uniform deformation stage, accelerated deformation stage. (3) in this paper, the time and space distribution of the cracks in each type of landslide is summarized, and the percentage of the time in the test time in each stage of evolution is counted. Based on the fracture penetration ratio-time curve and from the point of view of landslide model test, it is concluded that 40% fracture penetration ratio can be regarded as the early warning value of landslide impending slide.
【学位授予单位】：华北水利水电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P642.22

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