Coal seam hard roof deep hole blasting relief technology and optimization

Blasting pressure release of roof deep hole in the fully-mechanized face interconnection can shorten the first collapse step distance of roof, to avoid rock burst disasters that may caused a large area of roof collapse. Based on the actual geological condition of 6303 working face interconnection in Jining No.3 Coal Mine, from the rock blasting mechanism, this article proposes the two schemes of blasting pressure release of roof interconnection. By using of Ansys-dyna finite dynamic analysis software, this paper simulates blasting effect to the two schemes of deep hole blasting. With the analysis of numerical simulation results, we achieve parameter optimization and obtain the best blasting scheme.