By numerical simulation, the study on basic roof fracture of 3-driving drifts in different mining phases shows： In the process of mining, basic roof strata controls the movement of upper soft strata, which is consistent with the basic roof; After mining start, failure areas occurs in the roof of roadways, then there are failure areas in the floor too; After the mining in upper face, fractures appears in sidewalls of middle roadway, more serious in the vicinity of mined-out areas. The basic roof changes into block structure above the pillars and large-scale fracture of pillars appears in the mined-out areas; After the mining in lower face, the fracture in the middle roadways enlarges. Basic roof changes into blocks above the pillars and large-scale fracture happens among the two pillars near the mined-out areas.%采用数值模拟方法，对工作面三掘进巷道基本顶在工作面不同回采阶段的结构破断特征研究构表明：工作面回采过程中，基本顶岩层对上覆软弱岩层的运动起到了控制作用，上覆软岩的运动跟基本顶一致；三掘进巷道开挖后，先在巷道的顶板出现破坏区，随后底板也出现局部破坏；上区段工作面回采后，中阃回采巷道的帮部出现破坏区域，且靠近采空区域的破坏程度更大，基本顶在煤柱上方破断形成块体结构，煤柱靠近采空区域出现大范围的破坏区；下区段工作面回采后，中间巷道围岩破坏区域加大，基本顶仍然在煤柱上方破断形成块体结构，两煤柱靠近采空区域都有大范围的破坏区。
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