Abstract:
It analyzed the blasting effects of the single blasting methods and combined blasting methods of deep ahead roof pre-blasting at different blasthole angles. FLAC
3D numerical analysis software was used to simulate the different blasthole angles of single blasting and combined blasting. Meanwhile, it carried out blasting tests under different parameters on site, measured the change of coal stress and drilling cuttings. Deep ahead roof pre-blasting could effectively reduce the stress level, high stress transferred to the deep coal rock, thus the unloaded region formed near the blasthole, and obtained the best blasthole angle of deep ahead roof pre-blasting.