为研究爆炸破碎区坚硬岩石波阵面后的动力变形规律,引入改进的C.C.Grigorian模型,建立高压状态方程,推导增量本构方程。基于LS-DYNA9703D二次开发平台编制用户子程序,计算坚硬岩石耦合装药时高围压条件下爆炸破碎区动力响应,并将计算结果与模型试验、弹性模型及PSEUDO_TENSOR模型的计算结果进行比较分析。结果表明:改进的C.C.Grigorian模型计算结果与试验结果比较一致,可用于高围压水平下爆炸破碎区坚硬岩石动力变形与破坏分析。由于考虑岩石破碎软化的影响,爆腔永久位移与弹性模型和PSEUDO_TENSOR模型的计算结果明显不同;波阵面后爆腔表面介质的速度衰减规律与试验结果较为相似;围压水平对爆腔膨胀后的永久位移有显著影响,围压水平越高永久位移越小;爆腔膨胀后的永久位移对松弛特征时间比较敏感。
The modified C. C. Grigorian model was introduced to investigate the dynamic deformations of hard rock near explosion cavity after wavefront, the equations under high pressure and the incremental constitutive equations were presented. The dynamic responses of coupled-charge rock near explosion cavity under high confining pressure were calculated by introducing user-defined subroutine based on the LS-DYNA9703D secondary development platform, and the calculation results were compared with other results of experiment, elastic model or PSEUDO_TENSOR model The results indicated that the calculation results of modified C. C. Grigorian model were in good agreement with the results derived from the similar experiment; and the modified C. C. Grigorian model was reasonable to investigate the dynamic deformation and fracture of hard rock near explosion cavity under high confining pressure after wavefront. Due to the softening effects of cracked rock, the permanent displacements of explosion cavity that calculated by using modified C. C. Grigorian model were obvious different from those based on elastic model and PSEUDO_TENSOR model, and the velocity attenuation of surface medium of explosion cavity after wavefront was in good agreement with those of experiment. The permanent displacements after expansion of explosion cavity were greatly affected by the values of confining pressure, and the higher the confining pressure was, the lower the permanent displacement was. The permanent displacements after expansion of explosion cavity were sensitive to the relaxation characteristic time.