南芬露天铁矿排土场高陡边坡稳定性分析及监测设计

Stability Analysis and Monitoring Design of High and Steep Slopes in Nanfen Open-pit Iron Mine Dump

为了研究南芬露天铁矿2号排土场高陡边坡的稳定性,深入分析了2号排土场工程地质资料,结合现场调查,建立了典型剖面的数值计算模型,运用FLAC^(3D)数值分析软件进行数值模拟计算,再现了边坡破坏演化过程。通过分析数值计算结果可以得到:(1)排土场边坡应力分布状态与层状堆积状态基本一致,边坡首先沿潜在滑裂面下部产生剪切破坏,而后在潜在滑裂面上部表现出张拉破坏,最后形成贯通滑裂面;(2)排土场边坡首先发生变形的区域位于坡体中下部,最大位移量约为265 mm,该区域为边坡变形的主控部位,其次坡顶也发生较大变形,最大变形量约为200 mm,据此得出边坡变形敏感区域位于坡顶和坡体中下部,应对这些区域加强监测。根据研究结果,对排土场边坡变形监测方案进行优化设计,并应用到工程实际中,取得很好的应用效果。

In order to study the stability of the high and steep slopes of the No.2 dump of Nanfen Open-pit Iron Mine,the engineering geological data of the No.2 dump was deeply analyzed.Combined with the field investigation,the numerical calculation model of the typical section was established,and the FLAC^(3D)numerical value was used.The analysis software carries out numerical simulation calculation and reproduces the evolution process of slope failure.Through the analysis of the numerical results,the following results can be obtained:(1)The stress distribution state of the dump slope is basically consistent with the layered accumulation state.The slope first produces shear failure along the lower part of the potential slip surface,then shows tensile failure at the upper part of the potential slip surface,and finally the penetrating slip surface formed;(2)The first deformation area of the dump slope is located in the middle and lower part of the slope,and the maximum displacement is about 265mm.This area is the main control part of the slope deformation.Secondly,the top of the slope also has a large deformation,and the maximum deformation is about 200 mm.According to this,it is concluded that the sensitive areas of slope deformation are located at the top of the slope and the middle and lower part of the slope,so the monitoring of these areas should be strengthened.According to the research results,the optimal design of the deformation monitoring scheme of the dump slope is carried out and applied to engineering practice,and a good applicable effect is obtained.