非充分采动采空区与煤岩柱(体)耦合作用机制及应用

 以镇城底矿为工程背景，通过理论分析、相似模拟、数值模拟和现场实测，研究了非充分采动采空区和煤岩柱(体)耦合作用机制。得出如下结论：(1) 不同的工作面布置产生不同的工作面构型、采空区形态和煤岩柱(体)形态，进而造成不同的耦合作用结果，采空区响应对实体煤岩柱(体)的应力及岩体破坏影响很大，数值模拟不可忽略采空区作用；(2) 推导出煤柱极限平衡区宽度表达式，分层开采单一分层时采高降低、大采高和错层位开采存在斜坡均导致煤柱极限平衡区宽度下降；(3) 垮落角对采空区和煤岩柱(体)耦合作用有重要影响，通过相似模拟确定了垮落角并用于数值模拟，得出非充分采动条件下工作面宽度L、最上部关键层跨度L1与垮落角θ之间的关系式；(4) 数值模拟显示非充分采动采空区承载增加，则支承压力相应降低，反之亦然，验证了非充分采动采空区和煤岩柱(体)的耦合作用，数值模拟若忽略采空区承载作用会造成支承压力偏大，应力集中区高度偏大，且位置降低，岩体破坏范围偏大；(5) 根据研究结果，现场将进风巷布置于采空区边缘下方，形成巷顶沿空巷道，该巷道处于整个回采系统应力最低区；而回风巷沿顶板布置，工作面两侧顺槽矿压问题均得到良好控制。

Mechanism of gob-pillar interaction for subcritical panels and its application

Mechanism of gob-pillar interaction for subcritical panels was studied against Zhenchengdi coal mine through theoretical analysis，physical modelling，numerical modelling and field observation. Different panel layouts were found to lead to the different shapes of panel and coal pillar. The gob behavior has the significant influence on the stress distribution and failure of the coal pillar which should not be ignored in the numerical modelling. The width of limit equilibrium zone of coal pillar is derived. When a slice of multiple longwall slices of a coal seam is being mined，the mining height is reduced leading to the reduction of the width of the limit equilibrium zone，and so are the high seam longwall mining and split-level longwall mining(SLM) due to their elevating section. The angle of break plays an important role in gob-pillar interaction. The angles of break were obtained and were used for numerical modelling. An expression for the panel width L，the span of the uppermost key stratum L1 and the angle of break θ is obtained. The numerical modelling shows that the more load the gob bears，the less the abutment pressure and vice versa，which is the result of the gob-pillar interaction for subcritical panels. The abutment pressure，stress concentration factor and failure zone were larger and the elevation of failure zone was lower if the influence of gob was not taken into account. According to the mechanism of gob-pillar interaction for subcritical panels，the air intake way was set under the gob edge(with roof along the gob rather than rib) in the least stressed zone in the entire panel system，and the air exit way was arranged along the roof，as such，the ground control problems for both gate roads are solved.