锦屏一级水电站G1002电塔塔基边坡失稳机理及防治对策研究

发布时间：2018-04-27 00:39

本文选题：电塔塔基滑坡 + 失稳机理　；参考：《西南交通大学》2014年硕士论文

【摘要】：2012年8月29日至30日,锦屏一级水电站施工区内外连降大雨,引发群发性地质灾害,锦屏一级水电站左岸G1002电塔塔基斜坡局部发生滑坡,造成电塔D腿裸露悬空,给电塔和整个输电线路的安全造成严重威胁。本文在详细野外勘查的基础上,深化G1002电塔塔基滑坡的工程地质条件,对滑坡进行了分区,分析了滑坡的形成条件,还原了滑坡发生的过程,探讨了滑坡的形成机理；运用极限平衡法,对滑坡残留体进行了稳定性定量计算；通过数值模拟方法,研究了滑坡残留体的稳定性和失稳过程及机理；在以上研究的基础上,针对性地提出了滑坡的两种治理方案。通过剖析此典型实例,以期能为高山峡谷地区电塔选址提供借鉴和参考。主要研究内容和成果如下： 1、根据详细的滑坡现场勘查和滑坡变形特征,介绍了G1002电塔塔基滑坡的详细特征,并进行了分区,介绍了每个区域的特征。 2、通过分析滑坡的工程地质条件和水文地质条件,归纳总结了滑坡的形成条件。得出陡峭的地形特征、有利的岩体和坡体结构、山洪对坡脚的淘刷及连续的强降雨是诱发滑坡的关键因素。 3、根据滑坡的工程地质条件和变形特点,还原了滑坡的失稳过程,具体可分为三个阶段：第一阶段,暴雨入渗,坡体饱和；第二阶段,山洪暴发,淘刷坡脚,前缘小范围坍滑形成；第三阶段,山洪继续淘刷,发生大范围坍滑,斜坡失稳下滑。并由此得出电塔选址的几点启示。 4、对电塔塔基前缘拉裂变形区的坍滑残留体进行了稳定性及下滑推力的定量计算,为治理工程设计提供了依据,得出在暴雨工况下残留体是处于不稳定状态的,需要进行治理。 5、应用FLAC-3D数值计算方法对坍滑残留体在天然和暴雨两种工况下进行稳定性和失稳机理模拟分析。计算结果表明,滑坡残留体在天然工况下位移量很小,处于稳定状态,在暴雨工况下处于不稳定状态,位移量较大,最大位移出现在前缘,残留体深部出现贯通剪切带。 6、根据上述对滑坡残留体的分析与计算,结合滑坡的地形和交通条件,提出了两种可行的治理方案,方案一为格构锚索框架梁,方案二为抗滑桩和裂缝封填工程。考虑到交通条件、施工难度和工程扰动,综合推荐格构锚索框架梁为G1002电塔塔基滑坡的治理方案。
[Abstract]:From August 29 to 30, 2012, heavy rain occurred inside and outside the construction area of Jinping I Hydropower Station, causing mass geological disasters. Local landslides occurred on the G1002 electric tower base slope on the left bank of Jinping I Hydropower Station, resulting in the bare hanging of the D leg of the electric tower. It poses a serious threat to the safety of the tower and the whole transmission line. On the basis of detailed field exploration, this paper deepens the engineering geological conditions of G1002 electric tower base landslide, divides the landslide, analyzes the forming conditions of landslide, restores the process of landslide occurrence, and probes into the forming mechanism of landslide. The stability of the residual body of landslide is calculated quantitatively by using the limit equilibrium method, and the process and mechanism of the stability and instability of the residual body of landslide are studied by numerical simulation. Two control schemes of landslide are put forward. By analyzing this typical example, this paper hopes to provide reference and reference for the location of electric tower in high mountain and canyon area. The main contents and results of the study are as follows: 1. According to the detailed site survey and deformation characteristics of landslide, the detailed characteristics of G1002 electric tower base landslide are introduced, and the characteristics of each area are introduced. 2. Through analyzing the engineering geological condition and hydrogeological condition of landslide, the forming conditions of landslide are summarized. The results show that steep topographic features, favorable rock mass and slope structure, scouring of slope foot by mountain torrents and continuous heavy rainfall are the key factors to induce landslide. 3. According to the engineering geological conditions and deformation characteristics of the landslide, the instability process of the landslide is reduced, which can be divided into three stages: the first stage, the infiltration of the rainstorm, the saturation of the slope body, the second stage, the flash floods, scouring the foot of the slope, In the third stage, the mountain torrents continue to scour and scour, resulting in large-scale collapse and slope instability. From this, the location of the tower several enlightenment. 4. The stability and sliding thrust of the residual body in the front crack deformation zone of the electric tower foundation are calculated quantitatively, which provides the basis for the design of the treatment project. It is concluded that the residual body is in an unstable state under the condition of heavy rain and needs to be treated. 5. The stability and instability mechanism of the residual body under natural and rainstorm conditions are simulated and analyzed by FLAC-3D numerical calculation method. The results show that the displacement of landslide remains is very small and stable under natural conditions, and unstable under rainstorm conditions, the maximum displacement appears in the front edge, and the through shear zone appears in the deep part of the residual body. 6. According to the above analysis and calculation of the landslide residual body, combined with the landform and traffic conditions of the landslide, two feasible treatment schemes are put forward, one is lattice anchor cable frame beam, the other is anti-slide pile and crack sealing project. Considering the traffic condition, construction difficulty and engineering disturbance, it is recommended that the frame beam of lattice Anchorage cable should be the control scheme of G1002 electric tower base landslide.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV223

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