FRACTAL STUDY ON BLASTING ENERGY OF TOP COAL

Based on the blasting softening technology for hard top coal in long-wall top coal caving, asimple fractal model of rock fracture is establishedto deal with dissipated energy of rock fracture andfractal dimension of rock fragmentation and to obtain the theoretical relation between the fractal dimension of rock fragmentation and explosive specific charge. The blasting experiment of simulationmaterial model is conducted to verify theoretical results. Taking the fractal dimension of crack distribution on the surface of top coal as an index afterblasting top coal, some blasting parameters are optimized and the best blasting plan (triangle blasthole)is finally determined in on-the-spot mining.