急倾斜煤层伪俯斜工作面机械化开采煤体运移规律研究

Study on the Migration Law of Mechanized Mining Coal Body in Pseudo-Inclined Working Face of Steep Coal Seam

为解决急倾斜煤层伪俯斜工作面机械化开采时,破碎煤体堆积与溜运引发的工作面通道堵塞问题,以贵州省某矿11807工作面为工程背景,采用物理试验和数值计算相结合的方法,对工作面布置参数、待采煤体界面演化和煤体运移特征进行研究,揭示了急倾斜煤层伪俯斜工作面溜运及堆积特征,确定了工作面角度合理布置参数。结果表明:急倾斜薄及中厚煤层伪俯斜工作面机械化开采时,机采区煤体在刨煤机截割作用下卸压、破碎;工作面部分煤体采出后,非机采区域的煤体发生变形破坏,出现破碎;机采区破碎煤体运移以沿溜槽的铅垂方向运动为主,矿压自溜区松碎煤体首先垂直于顶板运动,继而出现平行于顶板方向的倾斜运动,最终沿工作面倾斜方向加速运移;溜槽工作面煤层倾角与溜运角呈线性函数关系;工作面伪倾角越大,煤炭资源相对采出率越高;当该工作面伪倾角为32°,伪斜角为49.7°时,工作面溜煤效果最佳。

In order to solve the problem of working face channel blockage caused by accumulation and transportation of broken coal in mechanized mining of pseudo-inclined working face in steep coal seam,11807working face of a mine in Guizhou Province was taken as the engineering background.The combination of physical experiment and numerical calculation was used to study the layout parameters of working face,the interface evolution of coal body to be mined and the migration characteristics of coal body.The characteristics of slip and accumulation of pseudo-inclined working face in steep coal seam were revealed,and the reasonable layout parameters of working face angle were determined.The results show that,during the mechanized mining of the pseudo-inclined working face in steeply inclined thin and medium-thick coal seams,the coal body in the mechanized mining area is pressure-relieved and broken under the cutting action of the plough.After part of the coal body at the working face being mined,the coal body in the non-machine mining area is deformed and broken.The movement of broken coal in the mechanized mining area is mainly along the vertical direction of the chute.The loose broken coal in the mine pressure self-slip zone firstly moves perpendicular to the roof,and then the obliquely moves parallel to the roof direction,and finally moves at an accelerated rate along the inclined direction of the working face.There is a linear function relationship between the coal seam dip angle and the slip angle of the chute working face.The greater the pseudo dip angle of the working face,the higher the relative recovery rate of coal resources.When the pseudo dip angle of the working face is 32°and the oblique angle is 49.7°,the coal slipping effect of the working face is the best.