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采用双轴伺服控制试验机对干燥和饱水花岗岩进行巷道岩爆模拟实验,同时采用声发射系统监测并采集数据,研究了水对花岗岩岩爆过程中声发射特征的影响。结果表明:岩爆过程中饱水岩样事件率呈上升趋势,峰值载荷前没有事件率平静期,而干燥花岗岩事件率呈下降趋势,峰值载荷前有明显的事件率平静期;自水平方向卸荷开始,岩样振铃计数率、能率突增,饱水岩样事件率高于干燥岩样,但振铃计数率、能率均低于干燥岩样,且有几段振铃计数率平静期,表明水的存在丰富了声发射活动,但降低了声发射信号强度,降低了微观破裂的活动性;干燥花岗岩振铃计数率峰值发生在峰值载荷附近,而饱水岩样振铃计数率峰值出现时距离峰值载荷较远;主破裂前声发射非均匀性指标Cv值的快速上升,表明岩样内部出现大破裂或裂缝贯通,声发射事件局部集中程度加强,造成其声发射事件分布的非均匀性增强,可作为岩爆发生的前兆特征。
The dual-axis servo controlled testing machine was used to simulate the rockburst in dry and saturated granite. At the same time, the acoustic emission system was used to monitor and collect the data to study the influence of water on the acoustic emission characteristics in granite rock burst process. The results show that the rate of water-saturated rock samples increases during the rockburst, and there is no event-rate quiescence before the peak load, while the dry granite event rate declines, with a clear event-rate quiescence before the peak load. From the beginning, the counting rate of rock ring rate, sudden increase of energy rate, and event of saturated rock samples were higher than those of dry rock samples. However, the counting rates and energy rates of ringing were lower than those of dry rock samples, , But the acoustic emission signal intensity is reduced and the activity of microscopic rupture is reduced. The peak value of ring counting rate of dry granite occurs near the peak load, while the peak value of ring counting rate of saturated rock sample appears The peak load is far away; the Cv value of the non-uniformity of acoustic emission before the main rupture rises rapidly, which indicates that large-scale or crack-penetrating occurs in the rock specimen and the local concentration of acoustic emission events is intensified, resulting in the non-uniform distribution of acoustic emission events , Can be used as a precursor to rock burst characteristics.