PENG Zhiyan,ZHA Wenhua.Research on optimization of staggered distance on simultaneous mining faces in ultra-close coal seams［J］.Industry and Mine Automation，2020,46（7）：94-99.

In view of problem that using existing ultra-close coal seam combined mining research methods to obtain mining staggered distance has bigger errors, taking No.9 and No.10 coal seams of a coal mine as engineering background, the mining pressure law of simultaneous mining face in ultra-close coal seams was analyzed under three kinds of mining staggered distances of 30, 36, 44 m. The evolution characteristics of working resistance changes and support pressure of the working face supports under the three mining staggered distance were studied. The results show that the working resistance of the support on 100402 fully mechanized working face decreases first and then increases with increase of mining staggered distance. The utilization rate of the working resistance of the support in the inclined direction of the 100402 fully mechanized working face has the most stable variation range under the 36 m mining staggered distance. The advance support pressure peak value of 090402 conventional mining face decreases first and then increases with the increase of mining staggered distance, which is consistent with the change law of working resistance of support. When the mining staggered distance is 36 m, the two roadways of the upper and lower working faces are affected by the advanced support pressure, the front roof bolt pressure changes steadily, the roof separation is small, and the amount of separation layer is basically stable within 0.6 mm, indicating that the 36 m mining staggered distance is reasonable, and the bolt pressure and roof separation in the advance section of the two roadways on the working face increase slightly, so the roadway support needs to be strengthened.