Experimental study on surface potential effect of coal under load
受载煤体表面电位效应的实验研究

In this paper, the characteristics and rules of surface potential effect of coal are studied under different failure mode, such as, uniaxial compression, tensile fracture and three-point bending by using the surface potential experiment system. Experiment results show that surface potential can be produced in the fracture of coal, and surface potential has a good correspondence with load and the correlation coefficient between them can reach up to 0.6 to 0.9. And the change of load will induce the change of surface potential correspondingly, and the larger the load is, the higher the surface potential becomes, vice versa. The distribution of surface potential is changing along with the change of load and fracture states of coal sample. The research of surface potential has a profound significance on deep study of the mechanism of electromagnetic radiation of coal fracture, also, on promoting the development and application of coal or rock electromagnetic radiation technology. And the further research of surface potential may provide a new method for assessing stress state and its stability of coal seam in mining filed, or monitoring and forecasting coal or rock dynamic disasters.