A blasting experiment was conducted on iron ore samples by considering multiple coupling charge coefficients. The resulting internal fracture and damage characteristics were quantitatively analyzed via computerized tomography (CT), scanning, and three-dimensional (3D) model reconstruction. The results show that the iron ore primarily displayed radial and circumferential cracks along the blast hole under an explosive load. When the decoupling coefficient was small, the crack surface was dominated by transgranular fractures in the form of intracrystalline fractures. As the uncoupling coefficient increased, the crack surface exhibited transgranular and intergranular coupled fracture modes. Using fractal theory to analyze crack distribution characteristics, as the decoupled coefficient increased, the body fractal dimension tended to decrease, and the degree of damage gradually decreased. The degree of damage reached a turning point when the decoupling charge coefficient was approximately 1.33. A numerical simulation suggested that the explosion energy transmitted to the iron ore and the effective stress decrease sharply when the decoupling coefficient exceeds 1.33. In some optimal uncoupling coefficient range, excessive fragmentation of the ore body is prevented, thereby allowing full use of the explosive energy.

考虑多个耦合电荷系数，对铁矿石样品进行了爆破试验。通过计算机断层扫描 (CT)、扫描和三维 (3D) 模型重建对由此产生的内部断裂和损伤特征进行定量分析。结果表明，铁矿石在爆炸载荷作用下主要沿炮孔出现径向和周向裂纹。当解耦系数较小时，裂纹表面以穿晶断裂为主，呈晶内断裂形式。随着解耦系数的增加，裂纹表面呈现穿晶和沿晶耦合断裂模式。用分形理论分析裂纹分布特征，随着解耦系数的增加，体分形维数趋于减小，并且损伤程度逐渐降低。当解耦电荷系数约为1.33时，损坏程度达到一个转折点。数值模拟表明，当解耦系数超过1.33时，传递给铁矿石的爆炸能量和有效应力急剧下降。在一些最佳解耦系数范围内，防止矿体过度破碎，从而充分利用爆炸能量。