基于切顶沿空留巷双向聚能爆破参数探讨

Discussion on Parameters of Bidirectional Shaped Charge Blasting Based on Roof Cutting and Gob Side Entry Retaining

通过理论和模拟试验结合的方法,分析了基于双向聚能爆破作用下煤矿巷道围岩定向断裂规律以及不同炮孔间距双孔聚能爆破围岩裂隙扩张延伸规律。分析表明:通过4+4+3+3+2方式的单孔装药结构的双向聚能爆破可以有效地定向断裂顶板,另外在炮孔的应力波叠加作用下裂纹进一步地扩展。模拟试验钻孔窥视显示,当炮孔间距为500 mm时,孔间形成良好的贯通裂纹,顶板断裂效果最佳。

Through the methods of theory and simulation test, the directional fracture law of surrounding rock under the action of bidirectional shaped charge blasting and the crack expansion law of surrounding rock under different spacing double hole shaped charge blasting are discussed and analyzed. The analysis results show that the bi-directional shaped charge blasting of 4 + 4 + 3 + 3 + 2 single hole charging structure can effectively fracture the roof, and the crack further expands due to the superposition of stress waves in the blast hole. According to the drilling peep, when the blast hole spacing is 500 mm, a good through crack can be formed between the two blast holes, and the roof fracture effect is the best.