应变率及节理倾角对岩石模拟材料动力特性的影响

采用相似材料模拟实验方法并借助SHPB(split Hopkinson pressure bar)实验系统，探究应变率及节理倾角对节理岩石动态力学性状的影响，包括应力应变曲线特征、破坏模式、能量传递及耗散规律。该实验结果表明:应变率升高，动态弹性模量增大，试件破碎块度变小，完整试件裂纹缺陷沿着平行于压应力方向扩展；节理角度越大，峰值强度越低，但当应变率升高到一定程度，节理角度对岩石破坏形态的影响不再明显；不同试件的入射能、反射能、透射能和耗散能均随应变率升高呈非线性增加，含倾斜角度节理试件的能量耗散率随应变率的变化幅度明显大于完整试件。

Experimental study for effects of strain rates and joint angles on dynamic responses of simulated rock materials

By using a split Hopkinson pressure bar (SHPB) technique, impact experiments were carried out on the jointed rock specimens simulated by cement-based mortar specimens. The dynamic responses of the simulated jointed rock material with different joint angles at different strain rates were analyzed including stress-strain curve characteristics, failure modes, energy transmission and dissipation. The experimental results show that, with the increase of strain rate, the dynamic elastic moduli increase, and the specimens become more fragile. The peak intensity decreases with the increase of the joint angles whereas when the strain rate increases to a certain extent, the influence of the joint angles on the rock damage formation is no longer obvious. The incident energy, the reflective energy, the transmission energy, and the dissipation energy of the different specimens nonlinearly increase with the increase of the strain rate. The energy dissipation rates of the specimens with inclination joint angles are higher than those of the intact specimens with the increase of the strain rate.