Tashan Mine,Datong Coal Mine Group Corporation Limited

为了研究特厚煤层大采高综放工作面能否采用小煤柱沿空掘巷技术,以塔山煤矿特厚煤层8204大采高综放工作面为工程背景,采用地表下沉量观测、微震观测和理论分析的方法研究了大采高综放工作面端部覆岩活动范围、裂隙场分布、运动特征及结构特征。结果表明:15 m特厚煤层大采高综放工作面垮落带高度为43 m,断裂带高度为43~200 m,200 m以上岩层处于弯曲下沉带内;大采高综放工作面端部以垮落角、移动角为边界形成滑移破裂区、拉压裂隙区和压裂隙区3个裂隙发育区;采空区稳定前工作面端部形成"下位悬臂梁-上位砌体梁"结构,随着工作面推进,覆岩进一步运动下沉,采空区稳定后下位悬臂梁破断,形成三角形滑移区,上位关键层仍以砌体梁结构方式存在,并控制侧向应力场的分布。

in order to study the gateway drving technocgy along the goaf whether could apply to or not to the high cutting rul-mechanized top coal caving miningface in uitra thick seam,.based on No.8204 high uting rul mechanized top coal caving mining face in ulrathick seam of Tashan Mine as an engineeing background.a surface ground subsidence observation,micro seismic observation and theoretcal nalysis method were appied to the studly on the overburden strata movement range,the cracks feldistribution,the movement features and structure features. The resuts showed that height ofthe rof fa赳ling zone in igh cutting rll- mechanized topcoal caving mining face in ulra thick seam wth a thickness of 15 m was 43 m,the height of cracks zone was 43 ~ 20 m and rock strata over 200 m above coal mining ace was in a bending and subsidence zone. with the of aling angle and moving angle as boundary:three crack development zones including the stlding breaking zone.ension and compression crack zone and compression crack zone formed at the end of high cutingfall - mechanized op coal caving mining face. Before the goaf stablized.a " ow cantilev er beam-upper bricks lined beam" struture was formed at the end of coal mining fac . Wih the cal mining face pushed fowar,the overburdenstrata would be further moved and subsided. Aferthe goaf stabilized,the low cantlever beam would be broken and a delta sliding zone was forme . The upper key layer would be still existed with mode of bricks lined beam structure and could control the distribution of the lateral stress field.

国家自然科学基金煤炭联合基金资助项目(U1261207)；