冲击地压预测的电荷感应技术及其应用

利用建立的煤岩电荷感应试验系统，研究煤岩变形破裂过程的电荷感应规律；利用研制的电荷感应仪对矿井进行现场测试。试验研究表明，煤岩在变形破裂过程中有电荷感应信号产生，煤岩体中应力越高，变形破裂过程越强烈，产生的电荷感应信号越强；在临近峰值应力前电荷感应信号最强，在煤岩体破坏后也有较强的电荷感应信号产生；抗压强度越高的煤样，电荷感应信号也越强，信号越丰富，持续时间越长。煤岩体变形破裂过程中产生电荷的主要原因是微破裂导致裂隙尖端电荷分离和摩擦作用。现场实践表明，测得的电荷感应值与煤体所处的应力水平是有一定关系的。在工作面平稳时期，测得的电荷感应幅值较小，而在发生冲击现象时测得的电荷感应幅值较大。利用电荷感应方法能够预测冲击危险的发生，但尚处于试验阶段，电荷感应预测技术还需要在现场不断验证和完善，以期最终为矿井冲击地压等煤岩动力灾害的非接触预测预报提供可靠的技术支持。

CHARGE-INDUCED TECHNIQUE OF ROCKBURST PREDICTION AND ITS APPLICATION

Using the experimental system for collecting the charge-induced signal of coal and rock，the research is made on the characteristic of charge induction during the deformation and fracture process of coal and rock. Using the self-designed charge-induced instrument，field test is done in coal mine. The experimental results show that the charge-induced signal generates during the deformation and fracture of coal and sandstone. The higher the stress in the coal or rock is，the stronger the deformation and the failure are，and the stronger the charge-induced signal is. The strongest charge-induced signal generated near the peak stress of coal or rock and the strong signal generated when coal damage. The higher compressive strength of the coal is，the stronger the charge-induced signal is and the longer the signal duration is. The primary principles of charge generation in the process of coal or rock deformation and fracture are friction and crack-tip charge separation because of micro-rupture. Field practice shows that there is a certain relationship of the charge induction value and the stress in the coal. The charge-induced amplitude is small in the stable period in the face，but the amplitude is large in the event of impact. The impact danger can be predicted by the charge induction method，but still the charge induction method is at an experimental stage. Charge induction forecasting techniques also need to continuously be validated and improved in the field. The reliable technical support is provided for the non-contact forecast to the mine dynamic disaster.