Experimental study on b-value dynamic characteristics during rock burst of sandstone samples with uniaxial loading

With the increase of uniaxial loadings, sandstone will occur acoustic emission (AE) phenomenon during the production and propagation of internal cracks, and failure. The stress-strain curve of sandstone and the relation of AE characteristics change with time can be obtained. The sandstone rock burst is studied by AE cumulative counts and the b-value reflecting the relation of magnitude and frequency. It is found that in the late stage of sandstone elastic deformation and plastic deformation, cumulative AE events increase rapidly, whereas b-value continues to decline, and before the sandstone rock burst occurs, b-value decreases to the lowest value. The combined analysis of cumulative AE events and b-value can more accurately predict the occurrence of rock burst.