Charge induction mechanism in the process of fracture of coal-rock

Using the self-developed charge inductor, a coal-rock charge induction test system and a temperature effect on coal-rock charge induction test system are developed under uniaxial compression to analyse the coal-rock charge induction. The study points out that the temperature rising of coal-rock can form thermal electron emission, but the main charge in the process of coal-rock fracture is not produced by thermal electron emission. According to the law of charge-energy, the perspective of the charge signal production is that the charge in the process of the coal-rock deformation and fracture is in accordance with the energy released by coal-rock. The more the energy is released by coal-rock, the more the charge is created. It demonstrats that the more energy is the cause for the stronger charge signal in the course of deformation and fracture of coal or rock. The higher the strength of coal-rock is, the more the charge will be created. At the same time, it accounts for the phenomenon that the coal-rock with different properties releases the same amount of energy but produces different charges in the process of coal-rock fracture. It may provide a reference for further studies.