不同地应力条件下切缝药包爆破的数值模拟

针对切缝药包定向爆破的特点，考虑岩石介质非均匀性的基础上，把岩石爆破视为爆炸应力波动态作用和爆生气体压力准静态作用的过程，基于损伤力学理论建立岩石爆破的力学模型，并对不同地应力条件下切缝药包爆破的裂纹演化规律进行数值模拟，分析不同地应力条件对切缝药包爆破效果的影响。模拟结果表明:采用切缝药包爆破时，裂纹主要萌生于切缝周边，沿切缝方向扩展，切缝对定向裂纹的控制作用明显；当考虑地应力作用，且最大地应力方向与切缝方向垂直时，不利于定向裂纹的扩展；最大地应力方向与切缝方向平行时，有利于定向裂纹的扩展。裂纹的扩展方向受控于切缝角度和最大地应力方向这2个条件，裂纹扩展规模则受到地应力的限制。

Numerical simulation on cutting seam cartridge blasting under different in-situ stress conditions

Based on damage mechanics theory, a mechanical model for rock blasting was established considering of the rock heterogeneity, in which rock blasting was considered as two consecutive stages: the dynamic stage caused by the stress wave and the static stage caused by explosion gas pressure. The cracks evolution of cutting seam cartridge blasting under different in-situ stress conditions was numerically simulated. The numerical results indicate that the blasting cracks mainly initiate around the cutting seam and propagate along the cutting seam direction. For different in-situ stress fields, the crack propagation will be suppressed when the maximum in-situ stress direction is perpendicular to the cutting seam direction, while promoted when the maximum in-situ stress direction is parallel to the cutting seam direction. The crack direction is controlled by the direction of cutting seam and maximum in-situ stress, while the crack propagation is suppressed by the in-situ stress field.