Fractal Characteristics of Coal Uniaxial Compression Acoustic Emission Test

To effectively forecast the dynamic disaster induced by coal rupture, fractal dimension calculation model of acoustic emission (AE) parameters were established using fractal theory. Study on the fractal characteristics of AE test signals generated by uniaxial compressing burst tendency coal were conducted. The results show that the AE energy box dimension gradually raises as the specimen loading process going on, and it reaches to the highest one before destruction, but the relevant dimension cuts down to a minimum before the destruction of the specimen. Gauss Amp equation could be used to describe the variation of AE energy relevant dimension with loading for coal under uniaxial compression loads. The continuous reduction of the AE energy relevant dimension could provide a precursor of instability or failure for coal mine. Results also give useful theoretical guidance for effectively forecasting dynamic disaster caused by coal rupture.