全息采空区与顶煤运移的时空演化规律研究

Study on Spatial and Temporal Evolution Law of Holographic Goaf and Top Coal Transportation

放顶煤开采是为解决特厚煤层高产与高效开采的新型方法,是我国特厚煤层开采的发展方向,但特厚煤层综放开采顶煤堵塞放煤通道的技术难题影响了煤炭的回收率。本项目结合塔山煤矿3-5;煤层的实际赋存条件,采用三维洞穴激光扫描仪和运用现场实测以及数值模拟等科学方法对其顶煤运移规律及采空区顶垮落形态等进行了系统的研究。研究结果表明:工作面在推进过程中,顶煤位移量发生变化,且工作面到达一定位置后,位移量变化明显;当处于顶煤体破坏的过程中,采空区方向的水平位移量与速度增长速率增加;顶煤和顶板运移量呈现2种截然不同的运移特征,前者壁前高于壁后,而后者为壁后高于壁前。

The future development direction of my country′s ultra-thick coal seam mining technology is the top coal mining method. Compared with traditional mining technology,its advantage lies in the high-yield and efficient mining of ultra-thick coal seams. However,the technical problem of blocking the caving channel of top coal in fully mechanized top coal caving mining in extra thick coal seam affects the recovery rate of coal. Based on the actual occurrence conditions of 3-5;coal seam in Tashan Coal Mine,by using three-dimensional cave laser scanner and scientific methods such as field measurement and numerical simulation,the law of top coal migration and roof caving in goaf are systematically studied. The results show that the displacement of the top coal changes during the advancing of the working face,and the displacement changes obviously after the working face reaches a certain position,the horizontal displacement and velocity increase in the direction of goaf,the displacement of top coal and the displacement of roof have two distinct migration characteristics:the former is higher than the latter,and the latter is higher than the former.