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针对岩爆监测研究的不足,开展了完整硬岩岩爆单轴压缩试验及全过程超声波监测,分析了完整硬岩岩爆破坏特征及超声波前兆规律,探讨了完整硬岩岩爆的预测预报。结果表明:对于完整硬岩岩爆,当加载载荷达到其峰值强度便产生噼啪声响,随之发生爆裂,通过分析碎片,发现试样靠近外部区域劈裂现象明显,越靠近试样内部其破裂面的粉化程度越严重,剪切现象越明显,是源于内部被约束程度的增加导致的强烈摩擦作用和高耗能的结果;通过对完整硬岩岩爆全过程超声波监测,发现波速由平稳不变发展到波动状态、首波波幅由微小的起伏波动发展到较大的起伏波动、衰减系数从增加转为下降均可作为岩爆发生的前兆;首波波幅由总体上减小转为明显增加也可作为岩爆发生的前兆,首波波幅由一直减小发展到微小起伏波动可作为岩爆发生的前兆;硬岩超声波频谱图可反映硬岩试样在载荷作用下其内部由变形发展到产生损伤再到破裂随即岩爆的过程。
According to the shortage of rock burst monitoring research, the uniaxial compression test of complete hard rock burst and the whole process of ultrasonic monitoring are carried out. The characteristics of complete rock burst and the precursory law of ultrasonic wave are analyzed. The prediction of complete rock burst is discussed. The results show that for the complete hard rock burst, the cracked sound is generated when the load reaches the peak intensity, followed by the burst. By analyzing the debris, it is found that the fracturing of the specimen near the outer region is obvious. The closer to the rupture surface The more severe the powdering phenomenon is, the more obvious the shearing phenomenon is due to the strong friction effect and the high energy dissipation caused by the increase of the internal restraint degree. Through the ultrasonic monitoring of the complete hard rock explosion process, it is found that the wave velocity is stabilized The volatility of the first wave fluctuated from slight fluctuation to larger fluctuation. The attenuation coefficient increased from increase to decrease can be used as a precursor of rock burst. The amplitude of the first wave decreased from the overall decrease to the obvious The increase can also be used as a precursor of rockburst. The fluctuation of the first wave amplitude decreases to a slight fluctuation, which can be used as a precursor of rock burst. The hard rock ultrasonic spectrum can reflect the deformation of the hard rock sample under the load To produce damage and then burst rock burst process.