冲击载荷作用下岩石动态力学性能的数值分析

Numerical Analysis of Dynamic Mechanical Properties of Rocks Under Impact Load

为研究不同冲击载荷和不同性质岩石的动态力学性能,通过与实验结果的对比分析,验证了数值仿真冲击载荷下应力波在岩石介质中传播特性的可行性,利用显式非线性动力分析有限元程序LS-DYNA,数值模拟了SHPB冲击岩石试件的过程,得到了不同冲击速度下人造岩石的应力-应变曲线,获得了相同冲击速度下几种不同性质岩石的应力-应变关系,结果表明,人造岩石的动态力学特性与应变率有很大关系,岩石的动态力学特性与岩性密切相关.

To study dynamic mechanical properties of different kinds of rocks at different impact velocities, the numerical results on stress propagation characteristics under impact load were proved by being compared with experimental results from references. With the explicit non-linear dynamic analysis program （LS-DYNA）, the process of the Split Hopkinson Pressure Bar （SHPB） impacting different samples of rock was simulated. Stress- strain curves of artificial rock at different impact velocities and that of four kinds of natural rock at the same impact velocity were obtained. The results show that the dynamic mechanical properties of artificial rock depend on the strain ratio, dynamic mechanical properties of natural rock relate closely to the lithology.