炸药类型对富铁矿爆破效果影响的试验研究

为探究炸药类型对铁矿石爆破效果的影响，选用相同药量的3种炸药对铁矿石试样进行爆破试验。对比研究了不同炸药爆炸作用后试样表面裂纹分形维数和碎块块度分布特征，进而对试样的破坏程度和爆破效果进行了定量的对比与评价。同时，从爆炸应力波叠加、能量释放与传递角度，对爆破效果的差异进行了理论分析。研究结果表明:（1）松散装药以及混合装药均会导致爆源相同距离处爆炸应力场分布的均匀性变差；（2）炸药爆热越大、炸药铁矿石波阻抗匹配程度越高，炸药爆炸后释放的能量越大且能量传递效率越高，铁矿石破坏程度越大；（3）爆破工程中炸药选型时，应重点考虑炸药密度、爆热和爆速3个参数，选择与矿（岩）体波阻抗匹配程度高且爆热合适的炸药，使得爆破后产生的大块和小块均较少。

Experimental study on the blasting effects of rich-iron ore with different explosives

In order to investigate the influence of different explosives type on the blasting effects, three kinds of explosives with the same quality were used to carry out blasting test on iron ore samples. The fractal dimension of surface crack and fragment size distribution of specimens were comparatively studied, and then the damage degree and blasting effects of specimens were quantitatively compared and evaluated. At the same time, the differences of blasting effects are analyzed theoretically from the angle of explosion stress wave superposition, energy release and energy transfer. The results are as follows. (1) Both loose charge and mixed charge will cause the uniformity of the explosion stress field distribution to deteriorate. (2) The greater the explosion heat, the greater the energy released after explosion; the higher the wave impedance matching, the higher the energy transfer efficiency after explosive explosion. (3) In the selection of explosives in blasting engineering, three parameters of explosive including density, explosion heat and detonation velocity should be considered; Explosives with a high degree of wave impedance matching and appropriate explosion heat should be selected so that the bulk and small pieces generated after blasting are less.