新疆和田县大红柳滩509道班西老滑坡稳定性分析  

Stability Analysis of the 509 Banxi Old Landslide in Dahongliutan County of Hotan County of Xinjiang

作　　者：李巧学 尚彦军[1,2] 伊学涛 李冬明 简相杰 崔君与 刘依 Li Qiaoxue;Shang Yanjun;Yi Xuetao;Li Dongming;Jian Xiangjie;Cui Junhe;Liu Yi(Xinjiang Key Laboratory of Geohazard Prevention(Xinjiang Institute of Engineering),Urumqi,Xinjiang,830023,China;Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,100029,China;University of Chinese Academy of Sciences,Beijing,100049,China;Xinjiang Qicheng Geotechnical Engineering Survey and Design Co.,Ltd.,Urumqi,Xinjiang,830099,China;Xinjiang University of Engineering,Urumqi,Xinjiang 830000)

机构地区：[1]新疆地质灾害防治重点实验室(新疆工程学院),新疆乌鲁木齐830000 [2]中国科学院地质与地球物理研究所,北京100029 [3]中国科学院大学,北京100049 [4]新疆启程岩土工程勘察设计有限公司,新疆乌鲁木齐830099 [5]新疆工程学院,新疆乌鲁木齐830000

出　　处：《新疆地质》2023年第4期609-613,共5页Xinjiang Geology

摘　　要：研究老滑坡稳定性有助于邻近工程建设的安全,尤其是在防治技术手段有限的高海拔大型古滑坡分布区。以和田县大红柳滩509道班西老滑坡对尾矿库坝影响为例,采用地质调查、钻探、现场力学原位测试、数值计算等技术方法对老滑坡整体稳定性进行分析。结果发现:①老滑坡后缘中上部局部存在拉张裂缝,该裂缝为滑坡体后缘山体风化剥落坡积物浅表变形张拉所致,坡积变形体厚度较薄,在重力或冻融作用下局部产生溜滑失稳破坏后再次处于平衡状态。目前变形阶段规模小,难以对整个滑体产生影响;②在天然条件下,老滑坡稳定系数为2.03,开挖时由于规模不同使老滑坡稳定性产生差异。在开挖垂高10 m且倾角为30°、45°、60°时,稳定系数分别为1.84、1.38、1.78;在开挖垂高20 m时稳定系数分别为1.69、1.09、1.07;在开挖垂高30m时稳定系数分别为1.69、1.09、1.07。当坡体前缘向下开挖30 m、坡度大于45°时稳定系数接近临界值1.0,易发生大规模破坏;③在老滑坡开挖过程中应实行信息化施工,在拉张裂缝位置布设GNSS位移监测设备或分段施工、分段回填,减弱老滑坡前缘因开挖卸荷产生的局部垮塌。同时在老滑坡堆积体上修建排水沟,将南侧和上部水导向北侧和尾矿库坝体下游,防止裂缝发展贯通产生老滑坡复活的地质灾害。Studying the stability of old landslides is helpful to the safety of adjacent engineering construction,especially in the distribution area of high-altitude large paleolandslides with limited prevention and control techniques.In this paper,the influence of the 509 Banxi old landslide in Dahongliutan in Hotan County on the tailings reservoir dam is taken as an example,and the overall stability of the old landslide is analyzed by geological survey,drilling,in-situ testing of onsite mechanics,numerical calculation and other technical methods.The results showed that:①There was a tensile crack in the middle and upper part of the trailing edge of the old landslide,which was caused by the superficial deformation tension of the slope sediment of the weathering spalling slope deposit at the trailing edge of the landslide body,and the thickness of the slope deformed body was thin,and it was in equilibrium again after the local slip instability failure under gravity or freeze-thaw,and it was difficult to affect the entire slide body due to the small scale of the current deformation stage;②Under natural conditions,the stability coefficient of the old landslide is 2.03,and the stability of the old landslide is different due to the different scale during excavation,and the stability coefficients are 1.84,1.38 and 1.78 when the excavation vertical height is 10m and the inclination angle is 30°,45°,60°,respectively,the stability coefficients are 1.64,1.38 and 1.78 when the excavation vertical height is 20m,and the stability coefficients are 1.69,1.09 and 1.07 when the excavation vertical height is 30m,respectively.When the leading edge of the slope is excavated 30m downward and the slope is greater than 45°,the stability coefficient is close to the critical value of 1.0,which is prone to largescale damage;③In the process of excavation of the old landslide,information construction should be implemented,and GNSS displacement monitoring equipment or sectional construction and sectional backfilling should be laid at the loc

关 键 词：老滑坡稳定性 地质调查 力学原位测试 数值模拟 

分 类 号：P642.22[天文地球—工程地质学]