含缓倾软弱夹层矿山高边坡滑动面位置与空间形态反演

Inversion of Sliding Surface Position and Spatial Morphology of Open-pit High Slopes with Gently-inclined Soft Interlayers

滑动面确定是边坡治理中的关键问题,传统的勘探技术在滑动面勘测识别确定过程中往往存在耗时、耗力、对坡体造成损伤、具有安全隐患等问题。为克服传统滑动面确定方法的局限性,以四川黄山含缓倾软弱夹层石灰石矿山高边坡为例,在边坡应急治理条件下,基于工程地质分析法、空间解析几何法、极限平衡法及强度折减法的综合应用,提出了一种以工程地质分析法为前提判断,空间解析几何法与极限平衡法为计算分析手段,强度折减法为检验保证的滑动面反演方法。首先根据工程地质分析判断出边坡整体及局部的破坏模式,其次利用空间解析几何法确定了滑坡体前后缘位置滑动面的空间形态,最后采用极限平衡法对边坡稳定性系数反复试算,进而反演出滑动面的具体位置,并基于有限元强度折减法对滑动面反演结果进行了分析验证。结果表明:边坡整体沿软弱夹层滑动,前后缘位置为圆弧滑动破坏,滑动面位于775 m平台到软弱夹层垂直距离为26 m的位置;有限元强度折减法计算的边坡稳定性系数为1.00,与滑动面反演结果基本一致,验证了该方法的可行性和准确性。研究结果为边坡滑动面的确定提供了一种新思路,对于类似边坡滑动面快速识别与确定及危岩体的应急治理具有一定的借鉴意义。

The determination of the sliding surface is the key problem in slope treatment,but the traditional explorationtechnology in the process of sliding surface survey and identification often exists time-consuming,labor-consuming,damage to the slope,with security risks and other issues.To overcome the limitation of traditional sliding surface determination method,taking the high slope with gently-inclined soft interlayers of Huangshan Limestone Mine in Sichuan as an example,under the condition of emergency treatment of slope,based on the comprehensive application of engineering geological analysis,space analytic geometric method,limit equilibrium method and strength reduction method,ainversion method of sliding surface was proposed,which takes engineering geological analysis method as the premise,spatial analytic geometry method and limit equilibrium method as the calculation and analysis means,and strength reduction method as the inspection guarantee.Firstly,the overall and local failure modes of the slope were determined according to engineering geological analysis.Secondly,the spatial morphology of the sliding surface at theforward and backward edges of the slope was determined by using the spatial analytical geometry method.Finally,the stability coefficient of the slope was calculated repeatedly by using the limit equilibrium method,and the specific position of the sliding surface was determined,and the sliding surface inversion results were verified by the finite element shear strength reduction method.The slope slides along the soft interlayers as a whole,and the forward and back edges were arc-shaped sliding failure.The results showed that the sliding surface was located at a position with a vertical distance of 26 m from the platform of 775 m to the soft interlayers.The slope stability coefficient calculated by finite element method shear strength reduction method is 1.00,and the feasibility and correctness of this method was proved.The above results provided a new idea for determining sliding surface and has certain reference significance for rapid identification and determination of similar slope sliding surface and emergency treatment of dangerous rock mass.