地下铁矿扩界开采地表影响范围计算

Calculation of Surface Influence Area for an Underground Expanding Iron Ore

矿山开采过程中往往会形成一定的空区造成地表的沉陷。为确保矿山的安全生产并提供地表影响范围计算的科学依据,针对某铁矿采用胶结充填法采矿需进行扩界开采的工程实际,将该矿的地表影响范围运用概率积分法和FLAC3D数值模拟软件进行预测。在已知该矿9条勘探线矿体形状的基础上,取地表沉陷数值为参考标准计算出地表最大变形区域;以FLAC3D建立矿山的仿真模型,真实反映矿区的三维地理、地质信息和各地层材料的内在属性,模拟开挖过程中地表变形的动态发展,最终确定地表变形等值线图。由此得出矿区开采中心部位沉降值为18mm,生产企业周围沉降值cm级以下,居民住房位于2 mm沉降圈以外,扩界开采带来的影响较小。地表监测数据进一步佐证了上述计算的准确性,扩界开采地表沉降范围计算可以指导矿山生产保证安全,有长远的意义。

The exploitation of underground mines generally has an effect on the earth＇s surface in some degree. To ensure safety and provide basis of calculation,probability integral method and flac-3d numerical simulation are applied to predict the area of surface subsidence according to the actual engineering condition that an iron ore will expand mining boundary with the cementing filling method. Based on nine prospecting lines,the surface deformation numbers is taken as the reference standard to obtain the maximum surface deformation area. A simulation model of mine is established via Flac-3d software to reflect the inner properties around the mining information of three-dimensional geographic,geologic information and formations. This method simulates the surface deformation in the process of dynamic excavation and eventually determines the surface deformation contour map. Expanding mining has little influence on the normal production of enterprises and residential life when the settlement value near the mining center is 18 mm,settlement value is under cm level around enterprises and residential buildings is out of settlement area at 2 mm. The surface monitoring data further verifies the accuracy of calculation above. Calculation of surface influence area for underground mining expanding can guide production and ensure safety in industry,and own a profound significance.