温压耦合作用下岩石动态破坏过程和机制研究

STUDY OF DYNAMIC FAILURE PROCESSES AND MECHANISM OF ROCK SUBJECTED TO COUPLING TEMPERATURE AND PRESSURE

温压耦合是深部岩石(体)的典型赋存环境。为揭示温压耦合下岩石的力学特性和破坏规律,采用实验和数值仿真相结合,研究岩石在不同温度和轴向静压力作用下的动态破坏过程,数值模拟再现温压耦合作用下岩石动态破坏性质的变化规律,给出温压耦合作用下岩石的动态破坏模式以及不同温度和不同轴向静压作用下破坏形态的差异。结果表明,在温度作用下,岩石发生膨胀导致热应力的产生;在相同轴向静压、不同温度作用下岩石的破坏形式相似,但是随着温度的升高,试样表面自由膨胀引起应力释放,而在试样内部会产生应力聚集,破碎更为粉碎。

Coupling temperature and pressure exist in deep rock generally. Laboratory experiments and numerical simulation have been conducted to study mechanics and failure character of rock subjected to coupling temperature and pressure. The dynamic failure process of rock samples subjected to coupling temperature and pressure are investigated. The numerical simulation reproduces variation of rock failure properties subjected to coupling temperature and pressure. The dynamic failure mode of rock under coupling temperature and pressure and the difference of rock failure characteristics with different temperatures and pressures are found. The results show that the thermal expansion cause producing of rock thermal stress with increased temperatures, and the failure mode is similar to those with different temperatures when the axial pressure is the same. However, there is greater failure degree because of the stress release on samples surface and stress accumulation within samples with increased temperature.