To investigate the effects of different unloading rates on rockbursts, the conventional triaxial compression tests and confining pressure unloading tests have been conducted on rock samples. The variation law of stress and stress thresholds for structural failure of rock sample under different confining pressures was analyzed, and the influence of different unloading confining pressure rates on limit storage energy during rock sample failure process was revealed. Experimental results showed that under uniaxial compression, the stress for structural failure of the rock sample is the same as stress thresholds for structural failure. In the conventional triaxial test, the stresses for structural failure and stress thresholds for structural failure of the rock sample will increase with the increase of confining pressure. Compared with the stresses for structural failure, the stress threshold for structural failure of rock samples increases by 32.88%, 53.63%, and 78.51%, respectively when the confining pressures are 10 MPa, 20 MPa, and 30 MPa. Under different confining pressure unloading rates, the limit storage energy of samples is also different. The higher the confining pressure unloading rate is, the smaller the limit storage energy is. When confining pressure increases, the limit storage energy of rock samples increases. Under the same initial confining pressure and confining pressure unloading rate, the change of axial pressure has little effect on the limited storage energy of rock, i.e., the energy required for rock failure is a definite value under certain conditions and is not affected by the stress loading path. This research can be helpful to understand and assess the rockburst during the deep rock mass excavation by different tunneling methods.

为了研究不同卸荷速率对岩爆的影响，已经对岩石样品进行了常规的三轴压缩试验和围压卸荷试验。分析了不同围压条件下岩石样品结构破坏的应力和应力阈值的变化规律，揭示了不同卸载围压速率对岩石样品破坏过程中极限储能的影响。实验结果表明，在单轴压缩下，岩石样品的结构破坏应力与结构破坏的应力阈值相同。在常规的三轴试验中，岩石样品的结构破坏应力和结构破坏应力阈值会随着围压的增加而增加。与结构破坏应力相比，当围压为10 MPa，20 MPa和30 MPa时，岩石样品的结构破坏应力阈值分别增加了32.88％，53.63％和78.51％。在不同的围压卸荷速率下，样品的极限储能也不同。围压卸载率越高，极限储能越小。当围压增加时，岩石样品的极限储能增加。在相同的初始围压和围压卸荷率下，轴向压力的变化对岩石的有限储能几乎没有影响，即岩石破坏所需的能量在一定条件下为确定值，不受应力的影响加载路径。