【摘要】 冲击矿压造成煤矿巷道及开采空间的破坏,其主要原因是冲击震源产生的振动波传递并扰动处于极限应力状态的煤岩体而诱发能量的突然释放。微震监测技术通过反映煤岩体变形破裂释放的能量以及频谱特征而实现冲击矿压的监测预报,其前兆信息研究是识别冲击矿压危险程度的关键。利用TDS–6微震采集系统测试三河尖煤矿组合煤岩试样变形破裂直至冲击破坏全过程的微震信号,发现在循环加载的后期,冲击前兆微震信号的低频成分增加,频谱向低频段移动,振幅较低,而试样冲击破坏诱发主震信号的高频成分增多,且振幅达到最大值。现场冲击矿压监测表明,前兆微震信号频谱中低频成分增加,且振幅开始逐渐上升。当冲击矿压发生时,主震信号的振幅达到最大值,频谱相对于前兆信号而言,高频成分明显增多。由此,微震信号的频谱向低频段移动,且振幅逐渐增加可以作为冲击矿压发生的一个前兆信息。这一结论对于利用微震监测系统监测预报冲击矿压具有一定的借鉴意义。更多还原

【Abstract】 The major reason that roadway or working face in coal mine is destroyed by rockburst is that the rockburst tremor generated by shock wave propagates and disturbs the coal-rock materials in the limit stress state.Microseismic(MS) technology can monitor and forecast rockburst by revealing indirectly energy release in deformation and fracture and frequency-spectrum characters of the coal-rock materials.To distinguish the danger classes of rockburst,the research on precursory information is a key question.By the TDS–6 MS test system,the MS signal of the compound coal-rock samples obtained from Sanhejian coal mine is studied in the processes of deformation,fracture and rockburst.It is found that the low-frequency components in precursory MS signals in the later period of cyclic loading will increase,the frequency-spectrum will move to low frequency band,and the amplitude is lower.But the high-frequency components in mainshock signals induced by rockburst will increase and the amplitude will increase suddenly to the maximum value.By monitoring the rockburst catastrophe on spot,the low frequency components in precursory MS signals will increase,and the amplitude will also begin to increase gradually.When rockburst happens,the amplitude of the mainshock signal suddenly increases to the maximum value,the high-frequency components will obviously increase compared to precursory signals.Based on the results,it can be believed as precursory information of rockburst that the frequency-spectrum of MS signals starts to move towards low frequency and the amplitude will also begin to increase.The conclusion will generate considerable important directive significance for monitoring and forecasting rockburst catastrophe with MS monitoring system in coal mines.更多还原