岩质边坡不同开挖条件下对断层影响机制研究

STUDY ON THE INFLUENCE MECHANISM OF SLOPE UNDER DIFFERENT EXCAVATION CONDITIONS

露天矿的开采会形成较大的边坡高度,大部分的露天矿都存在断层,使得边坡体的变形破坏机制及稳定性问题变得极为复杂,对矿山人员以及安全的生产产生很大的危害。因此,本文应用FLAC3D数值模拟软件对露天矿含断层边坡两种开挖进行模拟研究。根据现场工程地质情况,选择合适的剖面作为研究对象,之后进行模型的建立、开挖、变形的监测,最终总结出边坡开挖时边坡上观测点的位移变形的规律以及开挖对断层所造成的影响。结果表明:竖向开挖与横向开挖均表明随着开挖的进行水平位移量增加,垂直位移量减少。断层的埋藏越深其垂直的位移量越大。竖向开挖与横向开挖均表明随着开挖的进行,水平主应力和垂直主应力的的值均在减小。整个断层面的水平主应力越靠近开挖区域越大,垂直主应力则越来越小。两种开挖方式的结果为断层面上的剪应力和正应力比值竖向开挖要大于横向开挖的。剪应力和正应力比值越大,那么断层就越不稳定。所以横向的开挖方式更加安全稳定。

Open pit mining will form a larger slope height,fault is found most of the open pit mine,the deformation failure mechanism and stability of the slope body problems become very complex,for mine personnel and safe production to produce a lot of harm.Therefore,this paper applies FLAC3D numerical simulation software to simulate the two kinds of excavation in open-pit mine.According to the field of engineering geology situation,choose the appropriate section as the research object,after model establishment,excavation,the deformation monitoring,finally sums up the slope mining slope displacement observation point on the law of deformation and excavation of the effects of the faults.The results show that vertical excavation and transverse excavation show that the vertical displacement decreases with the increase of horizontal displacement.The deeper the fault is buried,the greater the vertical displacement.The vertical excavation and transverse excavation show that the value of horizontal principal stress and vertical principal stress is decreasing with the excavation.The horizontal principal stress of the whole fault surface is closer to the excavation area.The vertical principal stress is getting smaller and smaller.The result of two excavation methods is that the ratio of shear stress and normal stress on the fault surface is greater than that of transverse excavation.The larger the ratio of shear stress and positive stress,the more unstable the fault.So the horizontal excavation is more secure and stable.