Research on Detection Technology of Concealed Collapse Column in Ultra-wide Fully Mechanized Working Face

In view of the problem that the potential concealed collapse columns in the ultra-wide working face with a width of more than 260 m will have a serious impact on the safety mining of the working face. Firstly, the technology of mine audio electric penetration was used to conduct a general survey of the water-bearing geological structure within the range of 40 m of the roof and floor in the working face, to provide a target area for exploratory drilling. Then the high-density electrical sounding in mine was used to delineate the range of the collapse column in the area suspected of collapse column, to provide accurate reference for subsequent treatment. The concealed collapse column in 19108 working face of Jinggong No.1 Coal Mine in Pingshuo Company was detected, the results show that the two combined methods can accurately locate the collapsed column in the working face with a width of 300 m, and the low-resistance reaction is shown in the results. It also indicates that the comprehensive geophysical prospecting method is an effective technical way to detect the water-bearing geological structure inside the working face in advance.