昭通地区古生界泥质岩滑坡特征及稳定性评价方法探讨

发布时间：2018-03-10 21:58

本文选题：昭通地区　切入点：古生界泥质岩　出处：《昆明理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：滑坡是较为严重的地质灾害之一,它常常会造成交通中断、河道堵塞淤积、掩盖村镇,给国家和人民的生命财产安全带来巨大损失。通过收集整理关于滑坡研究相关文献资料,初步掌握滑带土研究现状及研究方法,明确了滑带土工程特性研究中存在的不足,即对区域性特殊滑带土的研究并没有达到令人满意的程度,无法满足当前和今后对某一特定区域地质灾害防治工作的要求。故本文以昭通地区古生界泥质岩(泥岩、页岩、板岩、粘土岩)软弱易滑岩土体构成的滑坡为研究对象,通过资料收集、野外调查、室内物理力学试验分析研究该类滑坡形成条件,为该区古生界泥质岩滑坡防治提供一定的指导作用。本文主要取得如下研究成果:(1)按滑面位置、力学性质、岩土体结构、滑坡规模、节理裂隙产状对该区古生界泥质岩滑坡进行分类,为探讨滑坡形成条件打下基础。统计得出,研究区古生界泥质岩滑坡滑动面以发育于全～强风化分界面最多,占统计样本总量的71.1%,泥质岩滑坡以小型牵引式居多。人工切坡至古生界泥质岩中风化层斜坡发生滑动的个数占该类斜坡的90%以上,而人工切坡至古生界泥质岩强风化层斜坡发生滑动的概率相比之下较小,仅占53%。(2)对研究区古生界泥质岩物理力学指标统计分析得出,全风化泥质岩粘聚力、内摩擦角较强风化泥质岩较小,而含水率、孔隙比较大,这也很好地解释了滑坡滑面发育于强～中风化层分界面多的原因;物理力学指标相关性分析得出,泥质岩内摩擦角随着含水率的降低,呈现较好的负相关关系。(3)对研究区典型古生界泥质岩滑坡建立三维模型,并结合定性评价方法综合评价其稳定性,采用极限平衡法对三维数值模拟结果进行验证,极限平衡法计算得出的稳定系数小于FLAC3D计算得出的结果,偏于安全。(4)从地形地貌,地质构造、岩土体性质及结构、地表水和地下水作用、人工切坡四个方面探讨研究区古生界泥质岩滑坡形成条件,并对其进行了防治。
[Abstract]:Landslide is one of the more serious geological disasters, it often causes traffic interruption, river channel blockage and siltation, cover up villages and towns, and bring huge losses to the life and property safety of the country and people. The present research situation and research methods of slip zone soil are preliminarily grasped, and the shortcomings of the study on the engineering characteristics of slip zone soil are clarified, that is, the research on regional special slip zone soil has not reached a satisfactory degree. It can not meet the requirements of the present and future geological hazard prevention work in a certain region. Therefore, the landslide composed of paleozoic mudstone (mudstone, shale, slate, clay rock) in the Paleozoic in Zhaotong area is taken as the research object. Through data collection, field investigation and laboratory physical and mechanical test, the forming conditions of this kind of landslide are analyzed and studied, which provides some guidance for the prevention and control of Paleozoic mudstone landslide. Mechanical properties, structure of rock and soil, scale of landslide, occurrence of joints and fissures are used to classify Paleozoic muddy rock landslide in this area, which lays a foundation for discussion of landslide forming conditions. The slip surface of Paleozoic mudstone landslide in the study area is the most developed at the interface of the whole to strong weathering. 71.1% of the total number of statistical samples, mudstone landslide is mostly of small traction type. The number of weathered layer slopes in artificial cut slope to Paleozoic mudstone is more than 90% of this kind of slope. However, the probability of sliding from artificial slope to Paleozoic mudstone strong weathering layer is relatively small, accounting for only 53% of the slope, and the statistical analysis of physical and mechanical indexes of Paleozoic mudstone in the study area shows that the cohesive force of fully weathered mudstone is obtained. The internal friction angle is stronger than the weathered mudstone, but the water content and porosity are relatively large, which also explains the reason that the landslide slide surface has more interface between strong and middle weathered layers, and the correlation analysis of physical and mechanical indexes shows that, With the decrease of water content, the internal friction angle of argillaceous rock presents a good negative correlation. (3) A 3D model of typical Paleozoic mudstone landslide in the study area is established, and its stability is evaluated synthetically with qualitative evaluation method. The limit equilibrium method is used to verify the results of 3D numerical simulation. The stability coefficient calculated by the limit equilibrium method is smaller than that obtained by FLAC3D. The forming conditions of paleozoic mudstone landslide in the study area are discussed in four aspects of surface water and groundwater action and artificial slope cutting, and the prevention and treatment are carried out.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P642.22

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