Abstract:
To effectively reduce the strong mining pressure in deep coal mine excavation, it is proposed in this study to drive a U-shaped roadway in the overlying strata of the coal seam, and effectively release the strong mine pressure through rock blasting. Based on the case of a deep coal mine located in the northwest, two different U-shaped roadway layout schemes are designed for hard rock, the burial depth is −800 m, −825 m and −850 m, −875 m, respectively. The results indicate that blasting in the U-shaped roadway significantly reduces stress and displacement in the working face during the coal mining process. It is shown that the effectiveness of the blasting for pressure relief in the U-shaped roadway is influenced by both relative layer spacing and mechanical behavior of the overlying strata. For the blasted rock strata with similar rock properties, a lower relative spacing between the U-shaped roadway and the coal seam can result in more effective pressure relief.