The collapse column development characteristics and the evaluation on water bursting risk of Wuyang coal mine

In order to prevent the collapse column conducting ordovician limestone water and making great mine flood, the basic characteristics of collapse column in Wuyang Coal Mine, Shanxi Province were analyzed and summarized. The development elevation of collapse column is above 650 m and the development is closely related to structure. The majority of primary collapse columns have poor water conductivity and the typical collapse column has six segments in vertical direction. Based on the No.7601 work face, the water bursting risk was analyzed by ANSYS finite element software during mining when there was a concealed collapse column under the coal seam. When the face is less than 50 m from the collapse column, the water flowing fracture of the collapse column affected by mining is connected with the face and makes the face effluent; with the face advancing, the water flowing channel extends to water inrush accident.