【摘要】 彬长矿区受高构造应力环境和上覆坚硬岩层影响，冲击风险显著，深孔预裂爆破是降低该区域冲击地压风险的有效手段。在高构造应力区开展深孔预裂爆破，其裂纹扩展形式尚不完全清楚。因此，采用LS-DYNA数值软件模拟分析了高构造应力环境、倾向与走向爆破孔倾角对爆破裂纹扩展的影响，基于模拟结果优化了现场爆破设计。结果表明：在最大水平主应力为主导的高构造应力条件下，裂纹扩展优势面总是沿着垂直于最小水平主应力方向的平面。水平应力差对爆破裂纹的扩展起到主导作用。增大水平应力差，爆破裂纹扩展的程度越高，且越利于爆破裂纹沿着炮孔所在平面扩展。不同的倾向爆破倾角下爆破裂纹扩展的差异性显著，而不同走向爆破倾角下裂纹扩展基本无变化。倾向爆破孔倾角大于75°时，爆破裂纹扩展程度高且裂纹扩展优势面沿着炮孔倾角所在平面。优化了现场爆破设计，现场试验后工作面大能量微震发生的次数与层位显著降低，波速异常系数峰值明显降低，爆破优化有效。更多还原

【Abstract】 The high-tectonic-stress environment and overlying hard rock layers of Binchang mine area pose considerable rock burst hazards to this mining area, and deep-hole pre-spitting blasting is an effective means to reduce rock burst hazards there. Nevertheless, the form of crack extension during the application of deep-hole pre-cracking blasting in the high-tectonic-stress region has not been clarified yet. In view of this fact, how high-tectonic-stress environment and blasting hole inclination angles in the dip and strike directions influence the results of blasting crack extension was simulated and analyzed with the aid of LS-DYNA numerical software. Based on the simulation results, the on-site blasting design was optimized. The following research results were obtained. Under high-tectonic-stress conditions dominated by the maximum horizontal principal stress, cracks tend to extend along the plane perpendicular to the direction of the minimum horizontal principal stress. The horizontal stress difference plays a dominant role in blasting crack extension. Increasing the horizontal stress difference contributes to raising the degree of blasting crack extension and is favorable for blasting crack extension along the plane where the blasting hole is located. Blasting crack extension differs significantly under different blasting inclination angles in the dip direction, while it barely changes under different blasting inclination angles in the strike direction. When the blasting inclination angle in the dip direction is greater than 75°, blasting cracks extend intensely along the plane where the blasting hole is located. On the basis of the above findings, on-site blasting design was designed. After the application of the optimized scheme, the number and position of high-energy seismic events in the working face are both reduced remarkably, and the peak value of the wave velocity anomaly coefficient drops notably. That is, the optimized scheme proves to be effective.更多还原