花岗岩的动态力学性能、本构模型与状态方程研究

为研究强动载荷条件下花岗岩的动态力学性能、本构模型与状态方程,分别采用分离式霍普金森压杆和轻气炮系统进行了压杆试验和飞片撞击试验,以获得不同条件下花岗岩的动态力学参数。压杆试验结果表明,花岗岩在应变率为80~320 s^–1范围内呈现明显的应变率效应,其强度和应变率近似呈指数关系。飞片撞击试验表明,随着飞片速度的增大,冲击波传播速度呈现明显的三折线变化趋势,而试样的可压缩性则随着加载速度的提高先逐渐增强然后再次降低。最后,根据试验数据,给出了强动载荷条件下花岗岩的HJC（Holmquist–Johnson–Cook）本构模型、Gruneisen状态方程以及动态屈服强度参数。

RESEARCH ON DYNAMIC MECHANICAL PROPERTIES,CONSTITUTIVE MODELS AND STATE EQUATIONS OF GRANITE

The purpose of this study is to investigate the dynamic mechanical properties, constitutive models and state equations of granite under strong dynamic loading conditions. To this end, split Hopkinson pressure bar (SHPB) and light gas gun (LGG) systems were used to conduct pressure rod tests and flyer plate impact tests to obtain the dynamic mechanical parameters of granite under different conditions. The results of the pressure rod tests show that granite exhibits a significant strain rate effect in the range of 80~320 s–1, with its strength and strain rate approximately following an exponential relationship. The impact tests show that the velocity of the impacting particles has a significant effect on the propagation velocity of the shock wave, with the compressibility of the specimen gradually increasing with increasing loading velocity and then decreasing again. Finally, based on the experimental data, the HJC (Holmquist–Johnson–Cook) constitutive model, Gruneisen state equation, and dynamic yield strength parameters of granite under strong dynamic loading conditions were given.