金属矿山不同采矿水平下的岩体变形规律分析,能为矿山地表移动沉陷范围的圈定及安全生产决策提供依据。以湖北鄂州程潮铁矿西区为例,依据近8 a监测所得的地表及深部岩体变形成果,对不同采矿水平下的岩体变形规律进行分析。结果表明:开采-290,-307.5和-325水平时,顶板岩体进入初始冒落阶段;开采-342.5水平时,顶板岩体进入了大量冒落阶段,其崩落是间断发生的;开采-358水平时,地面沉降漏斗均匀扩展,岩层移动表现出很强的连续性;开采-375水平时,围岩进入快速向外扩展阶段,边界线、移动线得到了较大的扩展,下盘沉降漏斗在2010年1月之后变为不均匀扩展,岩层移动出现了突变性;开采-395水平时,围岩进入扩展放缓阶段,边界线、移动线基本未向外扩展,下盘沉陷坑区域变形仍旧非常剧烈,没有减缓的趋势。
Investigation of ground deformation at different mining levels of metal mines may offer the decisions of delineating the scope of the surface movement and subsidence and safe production. In situ monitoring data on ground surface and in deep underground in the west part of Chengchao iron mine over the period of 8 years were collected and the regular pattern of ground deformation under different mining level were analyzed. When mining the levels of-290,-307.5 and 325,the roof stratum entered its initial caving stage. When mining the level of-342.5,the roof stratum entered the stage of the large amount of caving intermittently. When mining the level-358,the ground deformation was continuous and the ground subsidence funnel broadened homogeneously. When mining the level-375,the surrounding rock mass entered the stage of rapid outward extension,the boundary and movement line of ground deformation extended largely,the ground subsidence funnel in the footwall broadened unevenly in January 2010,and the ground movement showed catastrophe. When mining the level-395,the surrounding rock entered the stage of a slow deformation,and the boundary line and moving line extended a little. The ground deformation was still very severe in the subsidence areas of the footwall and appeared no tendency of ceasing