程潮铁矿西区地下开采引起的地表下沉规律初探

Research on the Surface Subsidence Laws During Underground Mining in the West of Chengchao Iron Mine

以鄂州程潮铁矿西区为工程背景，对矿区地下采矿活动引起的地表下沉规律进行了研究。结果表明：地下开采后，矿区不同区域所表现出的不同的沉陷规律主要是采空区的形态所造成的；目前矿区采空区项部不存在空区，即使有，也只存在小的空区；当矿体平均开采深度与回采累计垂直高度的比值k在5．1～5．9范围时，矿区地下采矿引起的变形会传播到地表并引起地表塌陷；下盘山上矿区公路、粉矿堆场和高压电塔南部区域进入了以自重应力为主的变形阶段，在岩层露头处出现台阶状的移动；上盘的下沉机理和煤层矿山很类似，在靠近采空区区域出现许多错断台阶。

Taking the west part of Chengchao iron mine in Erzhou as the engineering background, the law of surface subsidence caused by underground mining was studied. The results were obtained as follows. Firstly, after mining, the laws of surface subsidence in different mining areas presen- ted various, which attributed to the shapes of goaf. Second- ly, there was no empty area in the top of goal, even if not, there was only small empty area. Thirdly, when the ratio be- tween the average mining depth of orebody with the stoping vertical height was in the range of 5.1-5.9, the deformation caused by underground mining would extend to the surface and led to subsidence. Fourthly, the mine road, the storage yard of fine ore and the south area of high-voltage tower on the footwall was in the deformation stage dominated by weight stress, and the stepqike movement occurred in the rock outcrops. Furthermore, the subsidence mechanism of hanging wall was quite similar to coal miner s, and many stepped cracks were found near goal.