基于电荷监测技术预测矿山动力灾害试验研究

为提高矿山动力灾害预测准确率,应用自主研制的电荷传感器,将标准煤样置于三轴压力室内进行应力-电荷试验。分析围压对煤样压缩破坏过程中电荷信号的影响。结合现场测试,揭示工作面开挖过程中煤体应力与煤壁表面感应电荷的时间和空间变化规律。试验结果表明,煤体压缩过程中电荷信号的变化与煤体所处的应力水平关系密切,处于应力集中区域和应力松弛区域的煤体有明显脉冲状电荷信号,原始应力区电荷信号平稳,电荷信号的变化超前于煤体应力的变化,围压对电荷信号有延缓、强化的作用。

Experimental Research on Mine Dynamic Disaster Prediction Based on Charge Monitoring Technique

In order to improve accuracy of predicting mining dynamic disaster,stress-charge experiments were carried out on standard coal samples in a triaxial pressure chamber with a self-developed charge sensor.Effects of confining pressure on the charge signal during the coal compression and fracture process were analyzed.At the same time,the regularity of coal stress and charge of the coal wall surface in time and space dimensions during working face excavation were revealed combining the field test.Experimental results show that the charge is closely related with the stress level of coal in the process of coal compression,that apparent pulse-shaped charge signals exist in the coal in the stress concentration region and stress relaxation region,charge signal in the original stress region is steady,and that the change of charge signal is ahead of the coal stress state,confining pressure plays a role in delaying and strengthening the charge signal.