跨采开切眼过程的应力分布规律研究

Study on Stress Distribution Laws of Crossing and Mining Open-off Cut

以龟兹煤矿A6-103工作面开切眼外错上行开采为背景,采用数值模拟和现场实测方法对综放工作面跨采下部开切眼过程中顶底板和煤层的应力分布规律进行研究。结果表明:A6-103工作面跨采下部开切眼过程中170~240 m,工作面距离开切眼10 m时,煤层和顶底板的垂直应力达到最大,实体煤侧煤体超前影响范围为50 m左右,采空区侧煤体超前影响范围为20m左右;顶板超前影响范围为40 m左右,底板超前影响范围为25 m左右;顶板8 m处采空区侧应力峰值,较实体煤侧下降了56%;底板2 m深处采空区侧应力峰值较实体煤侧下降了26.6%;190~230 m过开切眼阶段支架增阻速率主要分布在0.5~1.4 MPa/min,数值明显大于其他区域。研究表明:数值模拟研究的应力演化规律基本和现场实测的应力演化规律基本相符。

Taking ascending mining of outward staggered arrangement in Qiuci A6-103 working face as the background,the stress distribution laws of coal seam,roof and floor in the process of crossing and mining lower open-off cut was studied by numerical simulation.The results showed that the vertical stress of coal seam and roof and floor reached the maximum when the A6-103 working face crossed and mined the lower open-off cut of 170 m to 240 m and the working face was 10 m from the open-off cut.The leading influence range of coal body on solid coal side is about 50 m,and the advanced influence range of goaf side coal is about 20 m.The leading influence range of roof is about 40 m,and that of floor is about 25 m.The peak stress on the side of goaf at 8 m of roof is 56%lower than that of the coal side.The peak stress on the side of goaf in the depth of 2 m of the bottom plate decreased by 26.6%compared with that of the solid coal;during the period of crossing and mining open-off cut 190 m to230 m,the increase rate of support resistance was mainly distributed between 0.5 MPa/min and 1.4 MPa/min,which was significantly higher than that in other areas.The results show that the stress distribution laws of the numerical model study is basically consistent with the stress distribution law measured in the field.