炮孔位置对含软分层煤体爆破致裂规律的数值模拟

Numerical simulation of blasting cracking law of hole position on coal with soft stratification

本文利用ANSYS/LS-DYNA有限元软件模拟了九里山矿含软分层煤体的爆破致裂情况,论述了含软分层煤体的致裂、裂纹扩展及能量传播规律,并重点探讨了炮孔位置对含软分层煤体的致裂效果。结果显示:炮孔位置对含软分层煤体的致裂规律有较大影响,其在影响下部硬煤层裂隙分布的同时也对上部硬煤层及软分层裂隙情况产生影响;综合分析爆炸能量、波阻抗匹配理论及模拟结果,得出了不同软分层厚度煤体存在不同的最优炮孔致裂位置的结论,其中,当软分层厚度为50cm时,最优炮孔位置为炮孔中心距软分层上表面以上35cm处。

Finite element software ANSYS/LS-DYNA is used to simulate the blasting cracking of soft layered coal body,and the fracturing,crack propagation and energy propagation rules of soft layered coal body are discussed.The results show that the location of gun hole affects the fracture distribution of the lower hard coal seam and also has a great influence on the upper hard coal seam and the soft stratification coal seam.Based on the comprehensive analysis of the theory of explosion energy and wave impedance matching and the simulation results,the conclusion is drawn that there are different optimal locations of shothole fracture in coal bodies with different soft stratification thickness.When the thickness of soft stratification is 50 cm,the optimal location of shothole is 35 cm above the surface of soft stratification from the center of the shothole.