Prediction and Application of the Height of Water-Conducting Fracture Zone in the Composite Roof: A Case Study of Jinxinda Coal Mine

The water inrush from the roof of coal mine is closely related to movement failure overburdened rock and height water-conducting fracture zone. In this work, based on research background disaster prevention control No. 2 seam roofs in Jinxinda Coal Mine, stability characteristics overlying working face are analyzed through combining theoretical analysis numerical simulation. According theory key strata, conditions hard soft analyzed, maximum zone 201 calculated be 35.72 m. crack evolution law composite was simulated using discrete element software. It found that basic (4.50 m thick) fine sandstone (7.64 two inferior development 36 m, which basically consistent with field measured results. Transient electromagnetic exploration technology used detect face, nine abnormal areas were found. order prevent influence disasters during mining, drilling verification carried out areas. verification, there no geophysical anomaly area, but management after mining should strengthened mining. expected results not only enrich formation mechanism; they also have important practical significance guiding safety production a mine.