为研究地下强爆炸岩石破坏动力效应,借助有关地下爆炸试验成果,研究强爆炸作用下岩石的单轴抗压强度、纵波速度及孔隙度等物理力学性状的变化规律,分析初始荷载强度、荷载压力波形等爆源参数对爆炸破坏效应的影响,对爆炸近区、剪切破碎区及非破坏荷载区岩石的状态方程分别进行阐述。结果表明:在地下强爆炸近区,岩石的单轴抗压强度降低,在距爆心35~40m/kt1/3的比例距离,岩石的单轴抗压强度与没有破坏时的单轴抗压强度值接近;爆源参数对岩石动力破坏效应有较大影响;破坏区半径、药室腔壁膨胀速度及最大质点速度等随爆源初始荷载强度的增大而增加;裂缝开展及分布尺度受荷载率的控制。
Dynamic effect of rock failure under underground intensive explosion is investigated by some results of underground explosion tests. The change laws of physico-mechanical characteristics including uniaxial compressive strength,velocity of longitudinal wave and porosity are studied;and the effects of explosion source parameters including initial loading density and pressure waveform on rock failure are analyzed. The state equations of rock in explosion near region,shear-crashed region and nondestructive loading region after explosion are established respectively. The results show that:In the near region of intensive explosion,the uniaxial compressive strength of rock decreases at the scale distance of 35–40 m/kt1/3. The parameters of explosion source have relatively great influence on dynamic failure effect of rock. The parameters such as radius of failure zone, expanding velocity of powder chamber wall and maximum particle velocity increase with the initial loading intensity of explosion source. The development and distribution of cracks are controlled by loading ratio.