叠加开采裂隙场演化与优势瓦斯通道形成机制

Evolution of crack field and formation mechanism of advantage gas channels in superposition mining

为获得近距离煤层群开采时上覆岩层瓦斯(甲烷)通道的形成与演化规律,采用相似模拟方法研究裂隙场的演化规律与瓦斯通道的形成机制。结果表明:采动裂隙场随工作面的推进,非匀速扩展,来压期间的扩展比正常推进期间快;采动裂隙场与工作面的推进具有同步协调的关系,且裂隙场可划分为裂隙发育区、裂隙贯通区、压实区;近距离煤层群的叠加开采加剧了采动裂隙场的演化,形成了纵横交错的瓦斯流动通道,且瓦斯的流动能力在优势瓦斯通道区、优势瓦斯通道过渡区、一般瓦斯通道区中依次减弱。

To understand the evolution and formation of gas（ methane） channels in overlying strata during mining close distance seam group,formation mechanism of crack fields in overlying strata was studied by using the method of similar simulation. The results show that mining crack field spreads non-uniformly with the face advancing,it expands faster during the weighting than normal,that the mining crack field has the relationship of synchronous coordination with the face advancing and can be divided into fractured development zone,fracture penetration zone and compacted area,and the evolution of mining crack field is exacerbate during the superposition mining in close distance seam group,the crisscrossed gas flow channels are formed and can be divided into advantage gas channel zone,transition zone of advantage gas channel and general gas channel zone,and the flow capacity of gas reduces in turn.