煤矿开采地表沉陷预测及其防治研究

Study on prediction and prevention of surface subsidence in mining of coal mine

以陕西某矿4号开采煤层为研究对象,通过地质条件分析和地表移动变形现场观测,得出非充分采动条件下对地表的沉降规律,并通过FLAC3D模拟进行验证。研究结果表明,仅有1个工作面开采时,地表下沉量很小,沉降系数为0.028,没有对地表的建筑物造成破坏;当2个工作面交替回采时,地表的沉降变形明显增大,沉降系数达到了0.15,属于非充分采动范围,不对地表建筑物造成破坏。开采工作面数量的增多不会增大地表的移动范围,使得地表下沉量和下沉速度显著增大,主要是受坚硬顶板的控制。当采深大于1.5 m以后,地表进入充分采动状态,地表建筑物将遭到破坏。研究结果阐明了煤矿工作面开采后的地表沉陷规律,也为相似地质条件矿井的地表沉降防治提供了参考。

Taking the No.4 coal seam of a mine in Shaanxi as the research object,through the analysis of geological conditions and the field observation of surface movement and deformation,the subsidence law of the surface under insufficient mining conditions was obtained,and the FLAC3D simulation was used to verify it.The research results showed that when only one working face was mined,the surface subsidence was very small,the settlement coefficient was 0.028,and there was no damage to the buildings on the surface;when the two working faces were alternately mined,the subsidence deformation of the surface was obvious and the settlement coefficient reached 0.15,which belonged to the scope of insufficient mining and did not cause damage to the surface buildings.The increase in the number of mining working faces would not increase the moving range of the surface,so that the surface subsidence and subsidence speed increased significantly,which was mainly controlled by the hard roof.When the mining depth was greater than 1.5 m,the surface would enter a state of full mining,and the structures on the surface would be damaged.The research results clarified the law of surface subsidence after mining in coal mine working face,and also provided a reference for the prevention and control of surface subsidence in mines with similar geological conditions.