巴谢河流域陈何村滑坡特征及稳定性研究

发布时间：2018-02-24 03:43

本文关键词： 滑坡特征稳定性模拟计算防治措施　出处：《兰州大学》2017年硕士论文　论文类型：学位论文

【摘要】：西北地区的黄土高原作为我国黄土的主要分布区,在造就特殊的黄土地貌景观的同时,黄土地质灾害亦频繁发育,特别是滑坡灾害的多成因、多类型、多期次的不断发生,给国家带来了巨大的经济损失和人员伤亡。本文以甘肃省巴谢河流域的陈何村滑坡为研究对象,通过野外对滑坡的详细调查,较为全面、系统的分析了滑坡的特征,探讨了滑坡的成因、形成机理及演化过程;评价了滑坡的稳定性,并提出对应的滑坡治理方案。主要研究成果如下:(1)通过野外调查,查明了滑坡的基本特征。滑坡平面形态总体表现为后壁平整光滑、前缘陡峭、裂缝发育、周界清晰;裂缝分布具有极不均匀性、成组排列性与长短伴生性等特点;变形破坏具体表现在后缘裂缝、错落、凹陷程度大,前缘土体破碎、错落高程大,两侧裂缝密集,中部裂缝相对稀疏等微地貌上;滑坡结构根据岩心由表及里依次呈现出松散黄土、短柱状黄土及中长柱状泥岩的变化过程。(2)统计对比分析了钻孔岩石质量指标RQD,确定了滑坡的类型,认为该滑坡属于黄土-泥岩接触面滑坡。(3)分析了滑坡的变形破坏特征及其成因,初步恢复了滑坡的形成演化过程,主要分为四个阶段:坡体蠕滑与裂缝形成阶段、裂缝扩展及润湿峰下移阶段、坡体后部块体瞬间下挫阶段、滑面贯通及滑坡发生阶段。(4)滑坡稳定性计算与数值模拟结果表明:滑坡发生后,该滑坡在天然工况下,处于稳定状态,在暴雨或连续降雨工况、地震等荷载作用工况下,均处于不稳定状态;挖除滑坡体前缘使公路保通后,该滑坡在天然状态、暴雨或连续降雨状态、地震等荷载作用状态等3种工况下,均处于不稳定性状态。提出了合理有效的防治方案:以削坡减载、抗滑挡墙及裂缝夯填为主,以地表排水工程、监测工程和绿化工程为辅。
[Abstract]:The Loess Plateau in Northwest China, as the main distribution area of loess in China, brings up special loess landform landscape at the same time, loess geological hazards also develop frequently, especially the occurrence of multiple causes, types and periods of landslide disasters. It has brought huge economic losses and casualties to the country. This paper takes Chen he Village landslide in the Basei River Basin of Gansu Province as the research object, through the detailed investigation of the landslide in the field, the characteristics of the landslide are analyzed comprehensively and systematically. The cause, formation mechanism and evolution process of landslide are discussed, the stability of landslide is evaluated, and the corresponding landslide treatment scheme is put forward. The main research results are as follows: 1) through field investigation, The basic features of the landslide are found out. The plane shape of the landslide is as follows: smooth back wall, steep front edge, crack development, clear circumference, extremely uneven distribution of fractures, group arrangement and long and long companion, etc. The deformation and failure are manifested in the microgeomorphology such as the rear edge crack, dislocation, large degree of depression, broken front soil mass, large dislocation height, dense cracks on both sides, and relatively sparse cracks in the middle part. According to the changing process of loose loess, short columnar loess and medium and long column mudstone, the rock quality index RQD of borehole is analyzed statistically, and the type of landslide is determined. It is considered that the landslide belongs to the loess-mudstone interface landslide. (3) the deformation and failure characteristics of the landslide and its origin are analyzed, and the forming and evolution process of the landslide is preliminarily restored. The landslide is divided into four stages: creeping and fracture forming stage. The calculation and numerical simulation results of the landslide stability at the stage of crack expansion and wetting peak downward, the instant collapse of the block at the back of the slope, the slide through and the landslide occurrence stage, and the numerical simulation results show that: after the landslide occurs, the landslide is under natural working conditions. Under the condition of rainstorm, continuous rainfall, earthquake and so on, the landslide is in the state of natural, rainstorm or continuous rainfall, and the landslide is in a natural state, rainstorm or continuous rainfall after the landslide is removed from the leading edge of the landslide to keep the highway safe. Under the condition of seismic iso-load action, all of them are in the unstable state. A reasonable and effective prevention scheme is put forward, which includes slope cutting, anti-slide retaining wall and crack tamping, surface drainage engineering, monitoring engineering and greening engineering.
【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P642.22

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