薛湖煤矿穿层水力冲孔周围煤体变形规律研究

Study on Coal Deformation Law of Hydraulic Flushing Passing Through Layer in Xuehu Coal Mine

为研究穿层水力冲孔后孔洞周围煤体变形规律,指导薛湖煤矿防治瓦斯突出,利用FLAC^(3D)软件及相关理论,对冲孔周围煤体的应力场、位移场分布规律进行数值模拟研究,分析了冲煤量对周围煤体应力和位移变化的影响,并现场试验。结果表明:薛湖煤矿穿层水力冲出煤量达1.54 t/m时,使孔洞周围煤体卸压,降低范围为2.26~3 m;孔洞上方顶板出现拉张应力,孔洞周围煤体产生指向孔洞的径向位移,位移大小与冲煤量正相关,位移范围为2.3~3.18 m,冲孔中部位移量大于底部。结合瓦斯抽采效果,综合分析比较,确定薛湖煤矿合理冲煤量为1.15 t/m左右。

In order to study coal deformation law of hydraulic flushing passing through layer to guide Xuehu Coal Mine to control gas outburst, based on the field test, we use FLAC^（3D） software and related theories to study numerical simulation of stress field distribution and displacement field distribution of coal around punching hole, and analyze the influence of the amount of coal on the stress and displacement of the surrounding coal and conduct the field test. We get a series of results, for example, when the amount of coal is up to 1.54 t/m, hydraulic punching makes coal pressure relief around the hole, and the range of the reduction of maximum principal is 2.26 m to 3 m. The tensile stress occurs on the top plate of the hole, coal around the hole forms radial displacement which is point to hole, the range of coal displacement is positively related with the amount of coal, and the range of which is 2.3 m to 3.18 m, and the displacement of the central part of the hydraulic punching is bigger than the bottom. Combined with gas extraction effect, we make comprehensive analysis and comparison to determine that the coal amount of about 1.15 t/m is the reasonable amount of coal in Xuehu Coal Mine.